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Dissertations / Theses on the topic 'Thermo gram'

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Published: 4 June 2021
Last updated: 5 February 2022

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1

Mikula, Martin. "Termodiagnostika - dotykové a bezdotykové měření teploty." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2014. http://www.nusl.cz/ntk/nusl-231525.

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This thesis is concerned with thermodiagnostics in industrial practise, which is very important for the assessment of technical condition of object on the basis of temperature, in today's time. It includes summary of contact and contact-free methods and their principle, advantages and disadvantages for aplication in industrial practise. Because of thesis it was carried out measurement in company Daikin Device Czech republic with the use of contact thermometer and two available thermocameras for solving of topical tasks relating to production.
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2

Sanchez, Carrillo Felipe. "Sterilization of Quebec's duck foie gras : thermal resistance of Clostridium sporogenes PA3679, thermo-physical properties of the product, and mathematical modeling of the sterilization." Master's thesis, Université Laval, 2015. http://hdl.handle.net/20.500.11794/26108.

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La résistance thermique de Clostridium sporogenes PA3679, ainsi que les propriétés thermo physiques comme la conductivité thermique, la chaleur spécifique, la densité et la diffusivité thermique ont été déterminées pour le foie gras produit au Québec et d'autres produits dérivées. Un modèle mathématique a été également développé pour simuler la température au centre (point froid) des conserves de foie gras. Les résultats obtenus pour la résistance thermique et les propriétés thermophysiques montrent, en général, un bon accord avec les données publiées. Ces valeurs ont été utilisées avec le modèle mathématique pour prédire la température à la zone la plus froide. Les températures prédites n’ont montré qu’une légère différence par rapport aux valeurs expérimentales. Avec ce modèle, la létalité totale de C. sporogenes a pu être aussi calculée, ce qui permet d’assurer la salubrité du produit et la sécurité des consommateurs.
Thermal resistance of Clostridium sporogenes PA3679, and the thermophysical properties as thermal conductivity, specific heat, density and thermal diffusivity were determined for the foie gras produced in Québec and other derivative products. A mathematical model was also developed to simulate the temperature at the center (coldest point) of the foie gras preserves. The results for thermal resistance and thermal properties show in general a good agreement with the published data; these values were used with the model and to predict the temperature at the coldest zone. The predicted temperatures have low error when compared to the experimental temperatures. With this model, the total lethality of C. sporogenes can be also calculated, providing the necessary information to secure consumer safety.
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3

Valle, Muñoz Rafael. "La gran aventura de Themo Lobos." Tesis, Universidad de Chile, 2011. http://repositorio.uchile.cl/handle/2250/170986.

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Seminario para optar al título de Periodista
En La Gran Aventura de Themo Lobos la recopilación de datos y fechas se entremezcla de manera constante con pormenores, anécdotas y alguna revelación sorprendente. Me gusta pensar que hoy todo eso sale a la luz como resultado de que un día, hace mucho tiempo, mis ojos de niño se asomaron a mirar el forado monstruoso que se abría en una portada de revista.
Ante la inexistencia de estudios biográficos y bibliográficos sobre el autor, este proyecto pretende subsanar de algún modo ese vacío. La Gran Aventura de Themo Lobos cuenta cómo se fue gestando, cómo fue creciendo y madurando una obra que atraviesa más de medio siglo y que ha anotado varios hitos en la cultura popular chilena contemporánea. Es 6 un relato armado tras muchas horas de conversación, de recuerdos, desahogos y reflexiones con su protagonista, y complementado con el testimonio de familiares, colegas, amigos, conocidos y gente que en algún momento cruzó su camino con el de este hombre. Debo mencionar, además, la valiosa ayuda que significaron los datos aportados por fans e investigadores del cómic local.
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4

Fonseca, Roberta Juliana Collet da. "Aplicação do modelo da soma-ponderada-de-gases-cinza a sistemas com superfícies não cinzas." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/163315.

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A radiação térmica é o principal mecanismo de transferência de calor em fenômenos que envolvem meios participantes em temperaturas elevadas, tais como em processos de combustão. A dependência fortemente irregular do coeficiente de absorção em relação ao número de onda torna desafiador o estudo de situações em que a radiação é apenas parte de um problema mais complexo. A exatidão do cálculo da radiação fica condicionada à solução da equação da transferência radiativa (RTE) por meio da integração linha-por-linha (LBL), sendo, muitas vezes, impraticável, em virtude do esforço computacional requerido para contabilizar as centenas de milhares ou milhões de linhas espectrais do coeficiente de absorção. Alternativamente, modelos espectrais, como a soma-ponderada-de-gases-cinza (WSGG), têm sido empregados de maneira eficaz na obtenção de resultados em substituição à integração LBL. Nessa dissertação, o modelo WSGG é aplicado na solução da transferência de calor radiativa em um sistema unidimensional, formado por duas placas planas paralelas infinitas e preenchido por uma mistura homogênea de dióxido de carbono e vapor de água, considerando-se perfis distintos de temperatura. Diferentemente da maioria dos estudos da literatura que empregam a mesma geometria, mas com paredes negras, o presente trabalho supõe superfícies cinzas e não cinzas. O objetivo central é, portanto, avaliar o erro em se assumir fronteiras negras quando estas não apresentam esse comportamento. Os resultados para o modelo WSGG aplicado a superfícies não cinzas, cinzas e negras são comparados com a solução linha-por-linha para paredes não cinzas. As análises dos desvios entre as soluções pelo modelo da soma-ponderada-de-gases-cinza e pela integração LBL mostram que a suposição de paredes negras, para casos em que as superfícies deveriam ser consideradas não cinzas, pode levar a erros de até 50% nos resultados para o fluxo de calor e para o termo fonte radiativo.
Thermal radiation is the main heat transfer mechanism in phenomena that involves high temperatures, such as in combustion processes. The strongly irregular dependence of the absorption coefficient on the wavenumber makes challenger the study of situations in which the radiation is only part of a more complex problem. The accuracy of the calculation of the radiation is conditioned to the solution of the radiative transfer equation (RTE) by line-by-line (LBL) integration, being frequently impracticable, due to the computational effort required to account for the hundreds of thousands or millions spectral lines of the absorption coefficient. Alternatively, spectral models, such as the weighted-sum-of-gray-gases (WSGG) model, have been used with success to obtain results in comparison to LBL integration. In this study, the WSGG model is applied to solve the radiative heat transfer in a one-dimensional system, formed by two infinite flat parallel plates and filled by a homogeneous mixture of carbon dioxide and water vapor, for different temperature profiles. Unlike most studies of the literature that employ the same geometry, but with black walls, the present work supposes gray and non-gray surfaces. The central objective is, therefore, to evaluate the error in assuming black boundaries when they do not present this behavior. The results for the WSGG model applied to non-gray, gray and black surfaces are compared with the line-by-line solution for non-gray walls. Analyzes of the deviations between the solutions by the weighted-sum-of-gray-gases model and the LBL integration show that the assumption of black walls, for cases where the surfaces should be considered as non-gray, may lead to errors of up to 50% in results for the heat flux and the radiative source term.
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5

Evon, Philippe Rigal Luc. "Nouveau procédé de bioraffinage du tournesol plante entière par fractionnement thermo-mécano-chimique en extrudeur bi-vis étude de l'extraction aqueuse des lipides et de la mise en forme du raffinat en agromatériaux par thermomoulage /." Toulouse : INP Toulouse, 2008. http://ethesis.inp-toulouse.fr/archive/00000668.

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6

Andrade, Nixon César de. "Desempenho térmico de cobertura verde utilizando a grama Brachiaria humidicola na cidade de São Carlos-SP." Universidade Federal de São Carlos, 2007. https://repositorio.ufscar.br/handle/ufscar/4626.

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This work aims to analyze the thermal behavior of a green roof with the Braquiária grass (Brachiaria humidicola), that reaches 1m height, comparing it with a traditional roof (concrete slab on show). Considering temperature and relative humidity data obtained through field measurements in different months, the thermal performance of the green and traditional roofs was analyzed. The inside and outside temperatures, and inside superficial of two test-cells were analyzed. The outside superficial temperatures were estimated through computation program and the solar radiation data and wind speed, necessaries for the use of this program, were provided by the Water Resource and Applied Ecology Center (CRHEA,) and the Engineering School of São Carlos (EESC), both from the University of São Paulo (USP). The results indicate that, submitted to the local climate, the green roof presents optimum performance, particularly for decreasing the temperatures of external and internal roof surfaces. In the same test-cell it was recently realized a similar research, which used the Esmeralda grass (Zoysia japonica), a short vegetation. Comparing the measurement results for cold and hot periods, it was noticed differences between the thermal performance of the two grasses.
O objetivo deste trabalho é analisar o comportamento térmico de uma cobertura ajardinada com a grama Braquiária (Brachiaria humidicola), que atinge 1m de altura, comparando-a com a de uma cobertura tradicional (laje exposta). Considerando-se os dados obtidos por meio de monitoramentos com aparelhos registradores de temperaturas e umidades relativas, em diferentes épocas do ano, analisou-se o comportamento térmico das coberturas tradicional e verde. Foram medidas as temperaturas do ar no interior e no exterior das células-teste e as superficiais internas de ambas as células. As temperaturas superficiais externas foram estimadas por programa computacional e os dados de radiação solar e velocidade do vento, necessários para a utilização desse programa, foram fornecidos pelo Centro de Recursos Hídricos e Ecologia Aplicada (CRHEA) e pela Escola de Engenharia de São Carlos (EESC), ambos da Universidade de São Paulo (USP). Os resultados indicam que, submetida ao clima local, a cobertura ajardinada apresenta ótimo desempenho, particularmente por amortecer as temperaturas das superfícies externas e internas da cobertura. Nessa mesma célula-teste realizou-se recentemente uma pesquisa similar, mas que utilizou a grama Esmeralda (Zoysia japonica), uma vegetação rasteira. Comparando-se os resultados dos monitoramentos realizados, nos períodos de frio e calor, foram detectadas diferenças entre os comportamentos térmicos das duas gramas.
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7

Miyazaki, Caroline Lumi. "Caracterização térmica, grau de conversão, resistência à flexão e dureza de compósitos comerciais tratados termicamente." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/23/23140/tde-18082010-124119/.

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Visando otimizar as propriedades químicas e mecânicas de compósitos de uso direto aplicados na forma indireta, associados a tratamentos térmicos experimentais (TT), torna-se necessária uma caracterização térmica que permita a determinação de uma temperatura de TT segura (abaixo da temperatura de início de perda de massa). Assim, a primeira etapa deste estudo consistiu em caracterizar termicamente dez compósitos comerciais (Z100, Filtek Z250, Z350 e Supreme XT- 3M ESPE, Esthet-X e TPH Spectrum Dentsply, Charisma Heraeus Kulzer, Tetric Ceram Ivoclar Vivadent, Herculite XRV e Point 4 - Kerr), fotoativados pelo método contínuo (C) e pulse-delay (PD) (20 J.cm-2), por termogravimetria (TG) (n=1) e calorimetria exploratória diferencial (DSC) (n=3). Foram escolhidas duas temperaturas de TT: 100 e 170°C, aplicadas por 10 min, 24h após a fotoativação. A partir disto, avaliaram-se: 1) o grau de conversão (GC), por espectroscopia FT-Raman (n=3); 2) a resistência à flexão em três pontos (RF) (n=10); e 3) a dureza Knoop (KHN) para as faces topo e base (n=3) de quatro destes compósitos (Filtek Z250 e Supreme XT, Esthet-X e Point 4), após diferentes condições: imediatamente, 1h, 6h e 24h após a fotoativação e 24h após fotoativação seguida de TT a 100 ou 170°C. Os dados obtidos foram submetidos à análise de variância e ao teste de Tukey (nível de significância de 5%). Quanto ao GC (%), houve significância estatística para o fator material (p=0,000): Point 4 (68,42) > Z250 (63,05) = Esthet-X (61,69) > Supreme (54,27); condição (p=0,000): TT170 (73,20) = TT100 (73,58) > 24h (62,60) = 6h (60,18) > 1h (55,10) = imediato (53,66); e ativação (p=0,006): C (62,97) > PD (60,75). Também foram significantes as interações material × condição (p=0,007) e material × condição × ativação (p=0,013). Para a RF (MPa), foram encontradas significâncias estatísticas para os fatores material (p=0,000): Z250 (165,48) > Supreme (153,96) > Point 4 (131,30) = Esthet-X (128,06); e condição (p=0,000): TT170 (194,56) > TT100 (182,91) > 24h (150,88) > 6h (131,79) > 1h (111,77) > imediato (96,30); assim como para as interações: ativação × condição (p=0,000), material × condição (p=0,000) e material × ativação × condição (p=0,000). Para a dureza, foram encontradas significâncias estatísticas para os fatores: materialativação (p=0,000): Supreme C (82,46) > Supreme PD (80,29) = Z250 C (77,46) > Z250 PD (74,30) > Esthet-X C (69,17) > Esthet-X PD (65,67) > Point 4 C (57,21) = Point 4 PD (56,71); condição (p=0,000): TT170 (81,35) > TT100 (73,72) > 24h (70,36) > 6h (67,92) > 1h (64,99) > imediato (64,12) e face (p=0,000): topo (71,40) > base (69,40); assim como para as interações: material-ativação × face (p=0,011), material-ativação × condição (p=0,000) e face × condição (p=0,000). A partir dos resultados obtidos, pôde-se concluir que os TTs experimentais propostos foram capazes de aumentar as propriedades estudadas, sendo, de maneira geral, os resultados obtidos com 170°C melhores do que os com 100°C, e ambos melhores do que as demais condições.
Aiming to optimize chemical and mechanical properties of direct composites applied in an indirect way, with an association to experimental heat treatments (TT), it is necessary a thermal characterization, in a way to determine a safe temperature for the TT (below the significant mass loss temperature). Thus, the first step of this study was to perform the thermal characterization of ten commercial composites (Z100, Filtek Z250, Z350 and Supreme XT 3M-ESPE, Esthet-X and TPH Spectrum Dentsply, Charisma Heraeus Kulzer, Tetric Ceram Ivoclar Vivadent, Herculite XRV and Point 4 - Kerr) photoactivated by continuous (C) and pulse-delay (PD) methods (20 J.cm-2), by thermogravimetry (TG) (n=1) and differential scanning calorimetry (DSC) (n=3). After that, two temperatures were chosen for the TT: 100 and 170°C, which were applied for 10 min, 24h after photoactivation. Thus, some properties were evaluated for four composites (Filtek Z250 and Supreme XT, Esthet- X and Point 4): 1) degree of conversion (GC) by FT-Raman spectroscopy (n=3); 2) three-point bending test (RF) (n=10); and 3) Knoop hardness (KHN) for top and bottom surfaces (n=3). The conditions were: immediately, 1h, 6h and 24h after photoactivation and 24h after photoactivation followed by TT at 100 or 170°C. Data were analyzed by ANOVA and Tukeys test (level of significance of 5%). In relation to GC (%), there were statistical significance for the factors material (p=0.000): Point 4 (68.42) > Z250 (63.05) = Esthet-X (61.69) > Supreme (54.27); condition (p=0.000): TT170 (73.20) = TT100 (73.58) > 24h (62.60) = 6h (60.18) > 1h (55.10) = immediately (53.66); and activation (p=0.006): C (62.97) > PD (60.75); and for the interactions: material × condition (p=0.007) and material × condition × activation (p=0.013). For RF (MPa), statistical significance were found for the factors material (p=0.000): Z250 (165.48) > Supreme (153.96) > Point 4 (131.30) = Esthet-X (128.06); and condition (p=0.000): TT170 (194.56) > TT100 (182.91) > 24h (150.88) > 6h (131.79) > 1h (111.77) > immediately (96.30); and also for the interactions: activation × condition (p=0.000), material × condition (p=0.000) and material × activation × condition (p=0.000). For KHN, statistical significance were found for the factors material-activation (p=0.000): Supreme C (82.46) > Supreme PD (80.29) = Z250 C (77.46) > Z250 PD (74.30) > Esthet-X C (69.17) > Esthet-X PD (65.67) > Point 4 C (57.21) = Point 4 PD (56.71); condition (p=0.000): TT170 (81.35) > TT100 (73.72) > 24h (70.36) > 6h (67.92) > 1h (64.99) > immediately (64.12), and face (p=0.000): top (71.40) > bottom (69.40); as for the interactions: material-activation × face (p=0.011), material-activation × condition (p=0.000) and face × condition (p=0.000). By the results, it could be concluded that both proposed experimental TTs were capable of increasing the studied properties, with, in a general way, 170°C generating better mechanical properties than 100°C, and both better than the other conditions.
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8

Kermarec, Andie. "Exsudation et rhéophysique des matériaux hétérogènes solide / liquide à base de corps gras." Thesis, Bordeaux 1, 2011. http://www.theses.fr/2011BOR14327/document.

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Le chauffage des matériaux cosmétiques peut provoquer une exsudation de surface sous la forme de petites gouttes puis un retrait des gouttes associé à un processus de recristallisation. Des méthodes rhéologiques et de diffusion multiple de la lumière ont permis une étude des effets d’exsudation et de recristallisation en fonction de la température de chauffage, du vieillissement et de la plasticité du matériau. Des simulations numériques et un modèle phénoménologique basés sur la prolifération de fissures métastables et la croissance hors équilibre d’amas de défauts liquides susceptibles de crever la surface permettent de rendre compte des effets d’exsudation et de recristallisation variables selon la plasticité de la matrice semi-cristalline et la teneur en huile dans le matériau soumis à une perturbation thermique
The heating of cosmetic materials can generate an external sweating phenomenon shown by the formation of droplets, followed by a withdrawal of the droplets due to the recrystallization process. Rheological methods and light scattering allowed to study the effects of sweating and re-crystallization in term of heating temperature, aging, and material’s elasticity. Numerical simulations and a phenomenological model based on the multiplication of metastable cracks and the growth outside of equilibrium state of liquid default pits able to burst the surface proves the sweating effects and the re-crystallization variable depending on the semi-crystalline matrix and the percentile of oil in the material under thermal fluctuation
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Rodrigues, Luís Gustavo Pires. "Aplicação do modelo da soma-ponderada-de-gases-cinza na simulação da transferência radiativa em chamas difusivas laminares de metano diluído com CO2 e N2." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/151382.

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Simulações acopladas do escoamento reativo e dos processos de transferência de calor para o estudo de chamas são problemas dispendiosos computacionalmente. A transferência de calor por radiação em processos de combustão, devido às elevadas temperaturas, é o processo de troca energética dominante. Ainda, o comportamento altamente irregular do coeficiente de absorção com o comprimento de onda se constitui em uma dificuldade adicional na modelagem da transferência radiativa em meios participantes. Para contornar essa dificuldade modelos espectrais foram desenvolvidos com o objetivo de simular o comportamento de um gás real. Dentre esses modelos destacam-se o gás cinza (GG: Gray Gas), o mais simples, que negligencia o comportamento espectral do coeficiente de absorção, e o modelo da soma-ponderada-de-gases-cinza (WSGG: Weighted-Sum-of-Gray-Gases) onde a integração sobre todo o espectro é substituída por um número finito de gases cinza. Com o avanço de ferramentas computacionais, principalmente códigos CFD (Computational Fluid Dynamics), abordagens computacionais se tornaram atrativas frente ou em complemento às abordagens experimentais. Desse modo, o presente trabalho tem por objetivo a aplicação dos modelos WSGG e GG com novas correlações na simulação detalhada de chamas difusivas laminares de metano diluído com dióxido de carbono e nitrogênio com o código CFD comercial ANSYS/Fluent. Foram desenvolvidas rotinas de usuário (UDF: User-Defined Functions) para o acoplamento dos modelos espectrais ao código CFD. A verificação das rotinas de usuário foi realizada comparando os resultados obtidos via simulação Fluent com dados obtidos pelo modelo WSGG com um código FORTRAN próprio desenvolvido pelo grupo de pesquisa do Laboratório de Radiação Térmica (LRT/UFRGS) para o problema unidimensional de superfícies negras e infinitas preenchidas por um meio não-isotérmico e não-homogêneo. Os erros encontrados para o fluxo de calor radiativo nas superfícies e para o termo fonte radiativo ao longo do meio foram da ordem de 1% indicando o funcionamento correto das rotinas UDF acopladas ao Fluent. Por fim, as rotinas foram aplicadas na simulação numérica para chamas de potência constante com diluição dos reagentes e os dados obtidos com a solução numérica foram comparados com dados experimentais para a fração radiante e fluxo de calor radiativo. Os desvios médios encontrados para o fluxo de calor radiativo ficaram em torno de 10% para todas as chamas, excetuando as chamas com diluição de CO2 de 30%, 40% e 50%, em volume, para as quais os desvios médios ficaram em torno de 15%. O termo fonte para as chamas apontou para a predominância da emissão do meio em relação à absorção. Todas as chamas estudadas se encontram no regime opticamente fino (optically thin) para o qual, segundo apontam estudos da literatura, a escolha do modelo espectral possui impacto pequeno em resultados globais da chama como a temperatura e a concentração das espécies na mistura. Nesse aspecto os resultados encontrados concordaram com a previsão da literatura, entretanto para a transferência radiativa, o modelo GG se mostrou sensivelmente menos preciso em comparação ao modelo WSGG, principalmente para a fração radiante e para o fluxo radiativo na região da pluma aquecida, indicando a dependência do modelo espectral adotado.
Coupled simulations of the reactive flow with the heat transfer processes for flame studying are computationally demanding problems. The radiative transfer in combustion processes is the main heat transfer mechanism due to the high temperatures involved. However, the highly irregular behavior o f the absorption coefficient with the wavenumber composes in an additional difficulty on modeling the radiative transfer in participating media. In order to overcome this issue, spectral models were developed with the objective of simulate the behavior of real gases. Some of the most known models are the gray gas (GG) for which the spectral behavior of the radiative properties of the medium is neglected and the weighted-sum-of-gray-gases (WSGG) for which the integration over the entire spectrum is replaced by a summation over a finite number of gray gases with constant absorption coefficients. With the development of computational tools, mainly Computational Fluid Dynamics (CFD) codes, numerical approaches became attractive instead or in complement of experimental set ups. In this way, the present work aims to couple the WSGG and the GG models with new correlations in a detailed simulation of diffusive laminar flames of methane diluted with carbon dioxide and nitrogen with the commercial CFD code ANSYS/Fluent. User-defined functions (UDF) were developed to the coupling of the spectral models. The verification was carried out through the WSGG model by comparing the Fluent solution with a solution obtained with a FORTRAN code developed by the Thermal Radiation Laboratory (LRT/UFRGS) research group for the one-dimensional system of black surfaces filled with a non-homogeneous and non-isothermal medium. The deviations for the radiative heat flux for the walls and the radiative heat source along the domain were of 1% or less, indicating the correct coupling between the UDF routines and the CFD code. Finally, the UDF were applied in the solution of constant power flames with fuel diluted with carbon dioxide and nitrogen. The obtained data was then compared with experimental measurements for the radiant fraction and the radiative heat flux along the flame axis. The average deviations found were in order of 10% for all flames, except for the flames with 30%, 40% and 50% of CO2 dilution, in volume, for which the deviatioms found were in order of 15%. The radiative heat source was plotted and indicated for the medium emission predominance in comparison with the medium absorption. All flames studied were optically thin flames for which, studies pointed, the spectral model have minor impact over global results as flame temperature and mixture concentration. For this aspect the results found showed agreement with the literature studies predictions, however the GG model showed itself less accurate in comparison with the WSGG model for the radiant fraction and the radiative heat flux computations. So the spectral models have influence on the radiative transfer even if its effect on flame structure can be negligible.
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Bezerra, Luciano Andr? Cruz. "An?lise do desempenho t?rmico de sistema constutivo de concreto com EPS como agregado gra?do." Universidade Federal do Rio Grande do Norte, 2003. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15548.

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Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
In the last decades there was a concentrate effort of researchers in the search for options to the problem of the continuity of city development and environmental preservation. The recycling and reuse of materials in industry have been considerate as the best option to sustainable development. One of the relevant aspects in this case refers to the rational use of electrical energy. At this point, the role of engineering is to conceive new processes and materials, with the objective of reducing energy consumption and maintaining, at the same time the benefits of the technology. In this context, the objective of the present research is to analyze quantitatively the thermal behavior of walls constructed with concrete blocks which composition aggregates the expanded polystyrene (EPS) reused in the shape of flakes and in the shape of a board, resulting in a “light concrete”. Experiments were conducted, systematically, with a wall (considerate as a standard) constructed with blocks of ordinary concrete; two walls constructed with blocks of light concrete, distinct by the proportion of EPS/sand; a wall of ceramic bricks (“eight holes” type) and a wall with ordinary blocks of cement, in a way to obtain a comparative analysis of the thermal behavior of the systems. Others tests conducted with the blocks were: stress analysis and thermal properties analysis (ρ, cp e k). Based on the results, it was possible to establish quantitative relationship between the concentration (density) of EPS in the constructive elements and the decreasing of the heat transfer rate, that also changes the others thermal properties of the material, as was proved. It was observed that the walls of light concrete presents better thermal behavior compared with the other two constructive systems world wide used. Based in the results of the investigation, there was shown the viability of the use of EPS as aggregate (raw material) in the composition of the concrete, with the objective of the fabrication of blocks to non-structural masonry that works as a thermal insulation in buildings. A direct consequence of this result is the possibility of reduction of the consume of the electrical energy used to climatization of buildings. Other aspect of the investigation that must be pointed was the reuse of the EPS as a raw material to civil construction, with a clear benefit to reducing of environmental problems
Nas ?ltimas d?cadas t?m sido grandes os esfor?os dos pesquisadores na busca por mais informa??es e conhecimentos sobre como se poder? continuar provendo o desenvolvimento das cidades sem que isso ocorra de forma agressiva ao meio ambiente. A reciclagem e o reaproveitamento de materiais que ainda possuem grande potencial de aplicabilidade s?o vistos como as solu??es mais evidentes em dire??o ao desenvolvimento sustent?vel. Um dos aspectos mais relevantes desse desenvolvimento refere-se ao uso racional da energia el?trica. E aqui se insere a Engenharia, com o papel de conceber t?cnicas e materiais inovadores cujo principal objetivo seja o de reduzir o consumo de energia el?trica, sem que obrigatoriamente se tenha que abrir m?o das comodidades conseguidas com sua aplica??o. Neste contexto, a presente pesquisa teve o objetivo de analisar de forma quantitativa o desempenho t?rmico de paredes constru?das com blocos de concreto cuja composi??o agrega o poliestireno expandido (EPS) reaproveitado na forma de flocos e em placas, constituindo desse modo um concreto leve. Realizaram-se experimentos, sistematicamente, com uma parede constru?da com blocos de concreto comum, considerada como refer?ncia; duas paredes com blocos de concreto leve, distintas pelas propor??es de EPS/areia; uma parede com tijolos cer?micos de oito furos e uma com blocos de cimento vazados, de forma a proceder-se com a analise comparativa dos desempenhos t?rmicos dos sistemas construtivos. Foram realizados ainda, ensaios de resist?ncia ? compress?o e ensaios de determina??o das propriedades termof?sicas (ρ, cp e k) dos blocos de concreto. Os resultados permitiram relacionar quantitativamente o efeito do EPS como agregado em elementos construtivos na redu??o da taxa de transfer?ncia de calor em fun??o da varia??o de densidade, que tamb?m interfere nas outras propriedades t?rmicas e mec?nicas do material, como comprovado. Constatou-se que as paredes de concreto leve apresentaram melhor desempenho t?rmico do que os outros dois sistemas construtivos consagrados comercialmente. P?de-se concluir que ? vi?vel empregar-se o EPS reaproveitado como material constituinte da mistura para concreto, com a finalidade de fabricar alvenaria de veda??o capaz de comportar-se tamb?m como isolante t?rmico entre o meio externo e o interno das edifica??es. Uma conseq??ncia direta disto ? a redu??o do consumo de energia el?trica utilizada pelos sistemas de climatiza??o, sem comprometer a situa??o de conforto t?rmico experimentada pelo usu?rio. Destaca-se ainda que o reaproveitamento do EPS como material de constru??o contribui com a redu??o dos problemas ambientais causados por este material. Al?m disso, os resultados obtidos neste estudo podem servir como refer?ncia aos projetistas na hora da escolha do material que ir? compor a alvenaria de veda??o, e assim poderem adequar os seus projetos ?s situa??es mais desej?veis
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Thoma, Rahere [Verfasser], Klaus [Gutachter] Theres, Ute [Gutachter] Höcker, and Wolfgang [Gutachter] Werr. "Functional Analysis of the GRAS Gene LATERAL SUPPRESSOR Arabidopsis Development of in Root and tomato / Rahere Thoma ; Gutachter: Klaus Theres, Ute Höcker, Wolfgang Werr." Köln : Universitäts- und Stadtbibliothek Köln, 2019. http://d-nb.info/1215293828/34.

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12

Sabatani, Emanuele. "Thermal Modeling and Control of a Capsule Welding Machine." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.

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This Master Thesis has been developed in collaboration with the IMA group. Its objective is to study an existing machine for coffee capsules production and to propose an alternative temperature controller for the welding process. In fact, one of the main issues of the apparatus is the difficult regulation of the temperature, because of its changing working conditions. Problems of high thermal inertia make the system not able to react quickly to the control action, especially at the beginning of the welding phase, creating difficulties in all the system and affecting the quality of the final product. This thesis has this structure: In Chapter 1 the mechanical structure of the machine is analyzed, empathizing the main aspects of the welding apparatus. Moreover, the electrical and electronic hardware is described, in order to realize how the control architecture of the welding apparatus works. In Chapter 2 models for simulation and control of the welding apparatus are developed, with the objective of obtaining a lumped parameter representation of it. Then, some simulations with Matlab/Simulink are carried out in order to check the behavior of the model. Techniques of Physical Modeling and System Identification are exploited together in order to obtain a realistic model of the heat transmission. The modeling phase is concluded in Chapter 3 where the obtained lumped parameter model is validated. Chapter 4 has the goal of analyzing and synthesizing an optimal control algorithm for the temperature regulation of the welding apparatus, with emphasis on the predictability and robustness of the control action in presence of varying working conditions. Chapter 5 is aimed at implementing the control algorithm in a commercial hardware. Then, the control software is validated in the machine, in order to verify its real effectiveness. Finally, Chapter 6 exhibits the conclusions and the further developments that are related to the study carried out in this thesis.
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13

Massimino, William. "Impact d’une manipulation thermique embryonnaire chez le canard mulard." Thesis, Pau, 2019. http://www.theses.fr/2019PAUU3050.

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Différentes études ont montré que des événements survenus très tôt dans la vie d’un animal pouvaient avoir des effets de « programmation » sur la physiologie de l’adulte. Récemment, il a été démontré que la manipulation thermique embryonnaire (MT) avait un impact sur le métabolisme hépatique chez les canards Pékin, 15 jours post-éclosion.Le premier objectif de cette thèse était de mesurer l’impact d'une MT embryonnaire sur les performances des canards mulards, utilisés pour la production de foie gras. Pour cela nous avons testé trois modalités expérimentales d’augmentation de température sur des embryons de canards mulards. Nos résultats ont montré que toutes nos MT embryonnaires augmentaient significativement le poids de foie (jusqu’à +16,9% ; P<0,0001) après gavage, par rapport au groupe contrôle (sans MT), associé à une augmentation du contenu lipidique dans les trois groupes MT (+2,5 à 3%). Ces résultats démontrent donc la grande reproductibilité de cette technique, et ouvrant la voie à une nouvelle procédure simple et peu couteuse pour la filière. Cependant, deux des groupes MT, présentant la même augmentation de température cumulée (+332°C) présentaient également une baisse d’éclosabilité et un taux de fonte lipidique à la cuisson plus élevé. Ceci laisse penser qu’une optimisation de la manipulation thermique embryonnaire pourrait être envisagée pour améliorer la qualité du foie gras, notamment en choisissant une MT modérée et discontinue. Dans un second temps nous avons donc entrepris d’identifier la meilleure fenêtre de MT possible sans dépasser les +332°C pour réduire les effets négatifs. Pour cela nous avons étudié l’expression de gènes d’intérêt dans le foie de canard mulard tout au long du développement. Nous avons mis en évidence un pic d'expression pour de nombreux gènes impliqués dans le métabolisme glucidique et lipidique autour du jour embryonnaire E20, suggérant qu'une réduction de la fenêtre de programmation pourrait être envisagée pour la production de foie gras chez le canard mulard. Dans une 3ème étude, nous avons étudié l’effet des MT embryonnaires sur l’expression, mesurée après gavage chez les canards âgés de 95 jours, de nombreux gènes impliqués dans le métabolisme lipidique et glucidique, le stress et les hormones thyroïdiennes. Après gavage, seules les expressions de quelques gènes semblent spécifiquement modulées par la MT embryonnaire. Ces résultats en cours d'analyse pourraient nous permettre d'identifier des cibles particulièrement sensibles aux MT appliqué pendant l'incubation, et jouant un rôle important dans le phénotype observé après gavage, caractérisé par un meilleur engraissement hépatique
Various studies have shown that events that occurred very early in the life of an animal could have "programming" effects on the physiology of the adult. Recently, it has been shown that embryonic thermal manipulation (TM) has an impact on hepatic metabolism in Pekin ducks, 15 days post hatch.The first objective of this thesis was to measure the impact of an embryonic TM on the performances of mule ducks, used for the production of “foie gras”. For that, we tested three experimental modalities of temperature increase on mule ducks embryos. Our results showed that all the embryonic TM significantly increased liver weight (up to + 16.9%, P <0.0001) after overfeeding, compared to the control group (without TM), associated with an increase in lipid content in the three TM groups (+2.5 to 3%). These results therefore demonstrate the great reproducibility of this technique, and pave the way for a new simple and inexpensive procedure for the industry. However, two of the TM groups have the same cumulative increase of temperature (+ 332 °C) also had a lower hatchability and a higher lipid-melting rate at cooking. This suggests that optimization of embryonic thermal manipulation could be considered to improve the quality of the “foie gras”, especially by choosing a moderate and discontinuous TM.In a second step, we therefore undertook to identify the best possible TM window without exceeding + 332 ° C to reduce the negative effects. For this, we have studied the expression of genes of interest in mule duck liver throughout development. We have demonstrated a peak expression for many genes involved in carbohydrate and lipid metabolism around embryonic day E20, suggesting that a reduction in the programming window could be considered for the production of “foie gras” in mule ducks.In a third study, we studied the effect of embryonic TM on the expression, measured after gavage in 95-day-old ducks, of numerous genes involved in lipid and carbohydrate metabolism, stress and thyroid hormones. After overfeeding, only the expressions of some genes seem specifically modulated by the embryonic TM. These results being analyzed could allow us to identify targets that are particularly sensitive to TM applied during incubation, and that play an important role in the phenotype observed after overfeeding, characterized by better fattening of the liver
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14

Fernandes, Cássio Spohr. "Implementação de modelos atualizados de gás cinza no software FDS para predição do fluxo de calor radiativo em incêndios." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2018. http://hdl.handle.net/10183/184710.

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Este trabalho tem como objetivo implementar e testar modelos de gás cinza atualizados na rotina de radiação térmica do software Fire Dynamics Simulator (FDS), além da utilização do próprio modelo de gás cinza disponível no software, para a predição do fluxo de calor radiativo. Os modelos de gás cinza estudados foram o modelo padrão do software FDS (aqui denominado como GC1), e os modelos de gás cinza mais atuais: o GC2, no qual o coeficiente de absorção do meio participante é dado por relações polinomiais, e o GC3, sendo este um modelo de gás cinza que baseia o cálculo do coeficiente de absorção no modelo WSGG. Os novos modelos de gás cinza foram implementados no código fonte do software FDS, o qual é um código aberto, e a verificação da implementação foi realizada através da solução numérica do equacionamento utilizando os valores reportados pelo software. Com os novos modelos de gás cinza já corretamente implementados, passou-se então para a simulação computacional dos casos previamente selecionados. Para todos os modelos de gás cinza, foram simulados incêndios em poças, para diferentes combustíveis (etanol, n-heptano e metanol) em diferentes cenários de incêndio, considerando ou não a presença de fuligem no sistema. Os cenários de incêndio eram: (i) totalmente fechado, (ii) totalmente aberto e (iii) com uma condição intermediária, fechado, porém com uma abertura para o meio externo. Um estudo de análise de malha e de diferentes parâmetros, como o estudo da quantidade necessária de ângulos sólidos discretos, foram realizados para correta padronização dos parâmetros. As simulações computacionais foram validadas para o modelo de gás cinza padrão do FDS através da comparação de resultados com aqueles reportados na literatura específica de cada caso. Com os modelos já validados simulou-se novamente cada cenário de incêndio com os diferentes modelos de gás cinza anteriormente implementados. A partir da análise dos resultados obtiveram-se boas concordâncias para os campos de temperatura, frações molares tanto de CO2 quanto de H2O e para as frações volumétricas de fuligem. Os fluxos de calor radiativos foram corretamente preditos para todos os modelos de gás cinza implementados. O modelo GC2 apresentou resultados com desvios médios na faixa de 15%, o modelo de gás cinza baseado no WSGG (GC3) apresentou os melhores resultados, com erros médios inferiores a 10%, enquanto que o modelo padrão do software, GC1, apresentou resultados intermediários.
This work aims to implement and test updated gray gas models in the thermal radiation routine of the Fire Dynamics Simulator (FDS) software, as well as the use of the gray gas model available in the software to the prediction of radiative heat flux. The gray gas models studied were the default model of the FDS software (determined GC1), and the most current gray gas models: the GC2, in which the absorption coefficient of the participant medium is given by a polynomial relations, and the GC3, which is a gray gas model that was based on the calculation of the absorption coefficient in the WSGG model. The most recently gray gas models were implemented in the source code, which is an open source, and the verification of the implementation was performed by the numerical solution of the equations from the reported values of the software. With the new gray gas models already implemented, the next step was the computational simulation of the previously selected cases. For all the gray gas models, pool fires were simulated different scenarios of fire for different fuels (ethanol, nheptane and methanol), with and without considering soot presence in the system. The fire scenarios were: (i) fully closed, (ii) fully open and (iii) with an intermediate condition, closed but with an opening to the external environment. A study of a mesh analysis and different parameters, such as the study of the required amount of discrete solid angles, were performed to correct the standard parameters. The computational simulations were verified for the default gray gas model of the FDS by comparing the simulations results with those reported in the specific literature of each case. With the models already verified, each fire scenario was simulated with the different gray gas models previously implemented. From the analysis of the results, good agreements were obtained for the fields of temperature, molar fraction of CO2 and H2O and soot volume fraction. The radiative heat fluxes were correctly predicted for all gray gas models early implemented. The GC2 model present results with average deviation in the range of 15%, the gray gas model based on WSGG (GC3) presented the best results, with average deviation lower than 10%, while the default software model (GC1) presented intermediate results.
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15

Ziemniczak, Aline. "Geração de novas correlações da soma-ponderada-de-gases-cinzas para espécies individuais de gases participantes." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2014. http://hdl.handle.net/10183/103827.

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Modelos numéricos envolvendo a transferência de calor por radiação em gases participantes são bastante complexos de ser resolvidos devido à dependência espectral das propriedades radiantes. Contudo, a radiação térmica não pode ser negligenciada em processos de combustão, onde as elevadas temperaturas envolvidas tornam a radiação o principal fenômeno de transferência de calor. O cálculo da transferência de calor por radiação envolve propriedades de absorção que variam de forma complexa com a temperatura e número de onda, sendo assim necessária a utilização de modelos espectrais para obtenção de resultados confiáveis com baixo tempo computacional. Neste trabalho, o método da soma-ponderada-degases- cinzas (WSGG) foi aplicado na resolução da transferência de calor radiante em um sistema unidimensional formado por duas placas finitas, paralelas e negras, para diferentes perfis de temperatura e de concentração de espécies químicas. Foram obtidas novas correlações para misturas de vapor d’água e dióxido de carbono, além de correlações para as espécies químicas individuais de vapor d’água, monóxido de carbono, dióxido de carbono e metano. A partir do banco de dados HITEMP 2010, as correlações foram geradas para três, quatro e cinco gases-cinzas. A partir das correlações obtidas para o modelo da somaponderada- de-gases-de-cinzas seus resultados são comparados com a solução benchmark obtida pela integração linha-por-linha (LBL). Para todos os casos propostos, é possível verificar uma boa concordância entre os resultados do método da soma-ponderada-de-gasescinzas com o método linha-por-linha.
Problems involving radiation heat transfer in participating media are in general very complex to be solved due to the dependence of the radiative properties with the wavenumber. However, thermal radiation cannot be neglected, especially in combustion processes due to the high temperatures that are involved, making radiation the main heat transfer mode. Calculating the heat transfer by radiation involves absorption properties which varies with the temperature and wavelength, therefore the use of spectral models are required to obtain good results with low computational time. In this dissertation, the weighted-sum-of-gray-gases (WSGG) model was applied to resolve the radiation heat transfer in a one-dimensional finite system formed by two parallel plates with black walls, for different temperature profiles and concentrations of the participating species. New WSGG correlations were obtained for mixtures of vapor water and carbon dioxide, besides correlations for the individual chemical species of vapor water, carbon monoxide, carbon dioxide and methane. From the HITEMP 2010 database correlations were generated for three, four and five gray gases. From the correlations obtained for the weighted-sum-of-gray-gases (WSGG) model, their results are compared with the benchmark solution obtained by integrating line-by-line (LBL). For all the proposed cases, in general, it is possible to observe a satisfactory agreement between the results of the weighted-sum-of-gray-gases with the line-by-line method.
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16

Dorigon, Leonardo Jovani. "Determinação dos coeficientes para o modelo da soma-poderada-dos-gases-cinzas a partir do banco de dados HITEMP 2010." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/55459.

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Neste trabalho são obtidos os coeficientes do modelo da Soma-Ponderada-dos-gases-cinza (WSGG) a partir do banco de dados HITEMP 2010, permitindo o uso do modelo com os dados mais precisos disponíveis atualmente. Neste trabalho também se faz uma comparação dos valores de emitância total obtidos a partir do modelo WSGG com valores benchmark, obtidos nesse trabalho, mostrando uma excelente concordância. Com os coeficientes obtidos, problemas unidimensionais de transferência de calor radiante são resolvidos de modo a comparar a solução obtida pelo modelo WSGG com a solução obtida pela integração LBL (solução benchmark). Nas comparações, diferentes perfis de temperatura, comprimentos de trajeto, gradientes de temperatura e concentrações de espécies são utilizadas. Em todos os casos é possível verificar uma boa concordância entre os resultados WSGG e LBL. Para comparações com perfil de temperatura parabólico, verifica-se erros locais abaixo de 8%. Para perfis de temperatura cossenoidais, é possível observar erros de até 18% para alguns casos, porém com erros médios menores que 1,6%.
In this work the coefficients for the Weighted Sum-of-Gray-Gases model (WSGG) are determined from HITEMP 2010 database, allowing the use of the model with the most accurate data available nowadays. This study also makes a comparison of the total emittance values obtained from the model with benchmark values, obtained in this work, showing an excellent agreement. With the obtained coefficients, one-dimensional radiant heat transfer problems are solved in order to compare the solution obtained by the WSGG model with the solution obtained by the LBL integration (benchmark solution). In the comparisons, different temperature profiles, path lengths, temperature gradients and species concentrations are used. In all cases it is possible to verify the good agreement of the WSGG and LBL results. For comparisons with parabolic temperature profile, the local error is below 8%. For cosine temperature profile, the local error is about 18% for some cases, but with average errors less than 1,6%.
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17

Simon, Annick. "Hydroxylation d'acides gras a chaine courte ou moyenne par des monooxygenases a cytochrome p 450 chez les vegetaux superieurs." Université Louis Pasteur (Strasbourg) (1971-2008), 1987. http://www.theses.fr/1987STR13183.

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18

Coelho, Felipe Ramos. "Geração de novas correlações da soma-ponderada-de-gases-cinza para H2O e CO2 em alta pressão." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/164594.

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A radiação térmica é frequentemente considerada um mecanismo de transferência de calor muito importante em processos de combustão em alta pressão, devido à presença de meios participantes e às altas temperaturas envolvidas. Resolver a radiação térmica em meios participantes é um problema complexo devido à natureza integro-diferencial da equação governante e à dependência espectral altamente irregular das propriedades de radiação. Atualmente, o método mais preciso para resolver a integração espectral é o método linha-porlinha (LBL), que possui um custo computacional muito elevado. Para contornar essa dificuldade, o problema espectral é geralmente resolvido usando modelos espectrais e, consequentemente, a equação da transferência radiativa (RTE) é simplificada. Um destes modelos é o da soma-ponderada-de-gases-cinza (WSGG), que substitui o comportamento espectral altamente irregular do coeficiente de absorção, por bandas de coeficientes de absorção uniforme e tem mostrado um bom desempenho em diversas aplicações, mesmo sendo um modelo bastante simplificado. Entretanto, recentemente alguns autores não obtiveram bons resultados ao tentar aplicar o WSGG a problemas de combustão em alta pressão. Este artigo desenvolve um modelo WSGG para CO2 e H2O em condições de alta pressão. Para validar o modelo, a emitância total é calculada usando os coeficientes WSGG e comparada à solução do LBL obtida usando o banco de dados espectrais HITEMP 2010. Os resultados mostraram grande convergência entre os valores de emitância de ambos os métodos, mesmo para valores de alta pressão, tanto para o CO2 quanto para H2O, provando que o método WSGG é aplicável a condições de alta pressão. O modelo também foi validado pelo cálculo do fluxo de calor e termo fonte radiativo, e comparando-os com os obtidos através do método LBL. O H2O teve melhores resultados para baixas pressões, enquanto o CO2 apresentou melhores resultados para pressões mais altas. O efeito da pressão total sobre a solução de LBL foi maior para o H2O, o que pode ser um dos motivos pelo qual os desvios foram maiores para os casos de alta pressão.
Thermal radiation is often a very important heat transfer mechanism in high pressure combustion processes due to the presence of participating media and the high temperatures involved. Solving thermal radiation in participating media is a tough problem due to the integro-differential governing equation and the complex spectral dependence of radiation properties. Currently, the most accurate method to solve the spectral integration is the line-byline (LBL) method, which has a very high computational cost. In order to avoid this drawback the spectral problem is usually solved using spectral models, and as a consequence the radiative transfer equation (RTE) is simplified. One of the models is the weighted-sum-ofgray- gases (WSGG) which replaces the highly irregular spectral behavior of the absorption coefficient by bands of uniform absorption coefficients, and has shown great performance a lot of applications even though it is a very simple model. However, recently some authors didn’t have good results when trying to apply the WSGG to high pressure combustion problems. This thesis develops a WSGG model for both CO2 and H2O on high pressure conditions. In order to validate the model the total emittance is calculated using the WSGG coefficients and compared to the LBL solution which was obtained using the HITEMP 2010 spectral emissivity database. The results showed that the emittance values from both methods were very close even for high pressure values for both CO2 and H2O proving that the WSGG method is applicable to high pressure conditions. The model was also validated by calculating the radiative heat flux and source, and comparing them with the LBL method. H2O had better results for low pressures while CO2 had better results for higher pressures. The effect of total pressure on the LBL solution was higher for H2O, which might be the reason why deviations were higher at high pressure values.
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19

Touffet, Maxime. "Transferts et réactivité de l’huile au cours du procédé de friture." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLA019/document.

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La friture profonde de type batch a été étudiée dans le projet FUI Fry’In (Réf. AAP17, 2014-2018) dans le but de proposer des innovations de rupture pour des friteuses batch domestiques et professionnelles. La thèse a appuyé le projet sur la maîtrise de deux effets négatifs de la friture : i) la thermo-oxydation de l’huile responsable des mauvaises odeurs et produits de dégradation ainsi que ii) la prise d’huile généralement favorisée au détriment de son égouttage. L’étude a été réalisée en combinant des mesures directes (spectroscopie et imagerie infrarouges en mode ATR, photo-ionisation, mesures DSC, imagerie rapide…) et modélisation multi-échelle (écoulement de l’huile et égouttage lors du retrait, description lagrangienne des réactions en présence d’un écoulement, couplage avec les ciné-tiques de dissolution de l’oxygène). La complexité du processus de thermo-oxydation a été réduite en considérant les hydroperoxydes comme une forme de stockage organique de l’oxygène, qui propage l’oxydation dans des régions en anoxie. Leur décomposition produit de nombreux composés de scission, dont la nature est influencée par les conditions locales de température et de concentration en oxygène. La prise d’huile a été décrite comme le bilan net entre l’huile charriée au moment du retrait et l’huile égouttée. L’égouttage a été étudié sur des barreaux métalliques et des produits réels. Il se conduit à la formation de quatre à huit gouttes en quelques secondes. Les cinétiques de drainage anisothermes ont été prédites par un modèle mécanistique. Le mécanisme spécifique de prise d’huile en cours de friture a été aussi analysé ; il se produit uniquement dans le cas des produits préfrits congelés
Batch deep-frying has been investigated within the collaborative project FUI Fry’In (ref. AAP17, 2014-2018) with the aim of proposing breakthrough innovations for small and medium size appliances. The PhD thesis was part of the project and focused on two specific adverse effects of deep-frying on food products: oil thermo-oxidation responsible for break-down products and off-flavors, and oil pickup process usually favored relatively to oil dripping. The work was carried out by combing direct measurements (FTIR-ATR spectroscopy and imaging, photoionization, DSC measurements, fast imaging…) and multiscale modeling (oil flow and oil dripping during product re-moval, Lagrangian description of reactions in aniso-thermal flows, coupling with oxygen dissolution kinetics). The complex problem of thermo-oxidation was split into simpler mechanisms by noticing that hydroperoxides are a kind of long-lived form of or-ganic oxygen, which trigger propagation in deep re-gions under anoxia. Their decomposition lead to various scission products, which were shown to be in-fluenced by both local temperature and oxygen con-centration. Oil uptake was described as the net balance between the amount of dragged oil during product removal and oil dripping at the tips of the product. The dripping process studied on both metal-lic sticks and real products occurs in less than few seconds and leads to a formation of four to eight drop-lets. The detailed drainage kinetics in anisothermal conditions were captured and predicted with the pro-posed mechanistic models. The specific mechanism of oil uptake during the immersion stage was eluci-dated and was shown to occur only in parfried frozen products
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20

Chyla, Ondrej. "Ověření účinku očkovadel na strukturu litiny s využitím termické analýzy." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-241930.

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This diploma thesis in the theoretical part deals with classification of cast iron, problems of gray cast iron production, methods of inoculation and valuation of the gray iron quality by means of thermal analysis. The aim of practical part was to investigate effectiveness of inoculation of two different inoculants using thermal analysis. In terms of mechanical properties, hardness and ultimate tensile strength were measured. Metallographic specimen were evaluating by means of image analysis software.
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21

Evon, Philippe. "Nouveau procédé de bioraffinage du tournesol plante entière par fractionnement thermo-mécano-chimique en extrudeur bi-vis : étude de l'extraction aqueuse des lipides et de la mise en forme du raffinat en agromatériaux par thermomoulage." Phd thesis, Toulouse, INPT, 2008. http://oatao.univ-toulouse.fr/7723/1/evon.pdf.

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L'extraction aqueuse des lipides de la graine de tournesol est étudiée en contacteur agité. La diffusion à l'intérieur des particules est le facteur limitant de l'échange de matière. Les protéines sont impliquées dans l'entraînement et la stabilisation des lipides par l'eau. Le fractionnement de la plante entière est également étudié avec l'eau en extrusion bi-vis. Un extrait et un raffinat sont obtenus séparément et en une seule étape continue. Des rendements d'extraction en huile de 55 % peuvent être obtenus sous forme d'émulsions huile/eau. Leur stabilité est assurée par la présence à l'interface de tensioactifs : les phospholipides et les protéines voire les pectines. Les extraits se composent aussi d'une phase hydrophile. Prépondérante, elle contient des composés hydrosolubles (protéines, pectines…). Riches en fibres, les raffinats présentent une teneur significative en protéines au comportement thermoplastique. Ils peuvent être transformés en agromatériaux par thermomoulage.
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22

Maluf, Omar. "Fadiga termomecânica em ligas de ferro fundido cinzento para discos de freio automotivos." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/88/88131/tde-23062009-151607/.

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Os discos de freio, durante a frenagem, são submetidos a tensões térmicas e mecânicas que podem ser relativamente altas quando muito bruscas (frações de segundo), situação em que a temperatura pode chegar a valores próximos de 600ºC. Esta variação de temperatura provoca choques térmicos que podem gerar trincas e/ou uma grande quantidade de deformação plástica no disco. A proposta deste trabalho foi a de investigar, através de experimentos, o comportamento mecânico e físico em quatro ligas de ferro fundido cinzento (A, B, C e E), utilizadas para produzir discos de freio de veículos automotivos. Para tanto, foram realizados ensaios termomecânicos de baixo ciclo em corpos de prova, entre 300ºC e 600ºC, nas condições em fase e fora de fase, adotando o critério de falha em 50% da tensão máxima (ASTM E-606) e em componentes (discos), além daqueles de difusividade térmica desde a temperatura ambiente até 600ºC. As curvas deformação em função da vida ( N) foram obtidas e analisadas segundo norma ASTM E 466/468. A análise microestrutural nos corpos de prova e peças, após os ensaios de fadiga, serviu para revelar a influência da morfologia e quantidade de grafita e da matriz sobre as propriedades mecânicas. A medição das difusividades térmicas teve como objetivo a verificação da influência do carbono equivalente e dos elementos de liga sobre esta propriedade física. Observou-se que, durante os ensaios de fadiga termomecânica em fase, em função da decomposição de parcela da cementita da perlita, houve, nos materiais, a chamada expansão grafítica, que teve influência na parte trativa do ciclo, diminuindo as tensões necessárias para se alcançar determinadas amplitudes de tensão mecânica. Pelos gráficos de amplitude de deformação mecânica em função do número de reversos para falhar, sob fadiga termomecânica em fase e fora de fase, observou-se que a melhor liga de ferro fundido cinzento foi a liga E. Esta constatação implicará em uma significativa redução dos custos de produção dos discos de freio, pois se poderá prescindir do elemento de liga Molibdênio, extremamente caro. Comparando-se os resultados de fadiga termomecânica com os de fadiga isotérmica a 25ºC, 300ºC e 600ºC, pôde-se verificar que os ensaios mais críticos foram os fora de fase, pois conduziram, comparativamente, a vidas menores.
Brake discs are submitted to thermal and mechanical stress that can be relatively high during abrupt braking action happens (fractions of seconds), causing the temperature to reach values as high as 600ºC. This temperature variation results in thermal shocks that can generate cracks and/or a large amount of plastic deformation in the disk. The main aim of this work was to investigate, through experiments, the mechanical and physical behavior of four alloys of gray cast iron (A, B, C and E), used to produce brake discs of automotives vehicles. Low cycle thermomechanical fatigue tests were carried out in components (discs) and in test specimens, between 300ºC and 600ºC, in the conditions in-phase and out-of-phase, adopting the failure criterion of 50% drop of the maximum tensile stress (ASTM E - 606). Thermal diffusivity values were measured from room temperature up to 600oC in order to analyze the effects of carbon content and alloying elements in physical properties. Curves -N were obtained and analyzed according to ASTM E 466/468 standard. Microstructural analysis was employed to reveal the influence of the matrix and morphology/amount of graphite on the mechanical properties. It was observed that, during in-phase thermomechanical fatigue tests, the volume expansion due to cementite decomposition into graphite and ferrite caused a decrease in the tensile stress necessary to achieve the mechanical strain imposed during tests. From M/2 x 2Nf graphs it was inferred that alloy E presented the best performance both in in-phase and out-of phase tests. The lack of Mo in this alloy implies in a significant reduction of cost production of the brake discs, due to the high cost of such alloying element. Out-of-phase thermomechanical fatigue tests resulted in shorter lives compared to isothermal fatigue tests carried out at 25ºC, 300ºC and 600ºC.
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23

Rosario, Adriano Murilo. "ESTUDO DOS EFEITOS DE ELEMENTOS DE LIGA NA SOLIDIFICAÇÃO DE UM FERRO FUNDIDO CINZENTO VIA ANÁLISE TÉRMICA." UNIVERSIDADE ESTADUAL DE PONTA GROSSA, 2012. http://tede2.uepg.br/jspui/handle/prefix/1448.

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Made available in DSpace on 2017-07-21T20:42:44Z (GMT). No. of bitstreams: 1 Adriano Murilo Rosario.pdf: 9074045 bytes, checksum: d9772c841442622e9ad77d48e4a5f6a2 (MD5) Previous issue date: 2012-10-22
The present study aimed at analyzing the effects of alloying elements on the solidification curves of a gray cast iron using the thermal analysis technique. Inoculation was performed by adding of only 0.02% (in wt. %) of IM22 inoculant, in order to minimize undercooling and provide a minimal quantity of nucleation sites for graphite during solidification. A constant inoculation condition allows highlighting the influence of alloying elements in the cooling curves, as well as in the solidification parameters. The following elements have been added to the base metal (in wt. %): selenium (0.2% to 0.5%), nickel (0.2% to 0.5%), iron-phosphorus (0.2% to 1.0%), silicon (0.05% to 0.4%), lead (0.2% to 1.0%) and tin (0.2% to 0.8%). The elementary powders were characterized by scanning electron microscopy (SEM) with energy-dispersive X-ray microanalysis (EDX). The base metal was produced in a medium frequency induction furnace and its chemical composition corresponded to a FC-25 class. The samples obtained after the addition of alloying elements were characterized by optical microscopy, optical emission spectrometry, tensile and hardness tests. The results showed that selenium has a strong effect on undercooling, favoring the formation of eutectic carbides. Nickel tends to favor the formation of type "A” graphite. The phosphorus has the effect of reducing the tensile strength of gray iron and promotes the formation of steadite, consisting of the eutectic of ferrite and iron phosphide (Fe3P). The silicon favors the formation of type "A" graphite. Lead has deleterious effect on the morphology of graphite. Tin has the effect of increasing the mechanical properties. The use of thermal analysis technique allowed the finding of good correlations between the different solidification parameters studied. The stable and metastable eutectic temperatures are strongly affected by the alloying elements. Finally, new equations for the temperatures of stable and metastable eutectics are proposed. The equations are based on experimental results and data extracted from ATAS program.
O presente trabalho teve por objetivo principal analisar os efeitos dos elementos de liga nas curvas de solidificação de um ferro fundido cinzento, utilizando a técnica de análise térmica. A inoculação foi adicionada em um teor muito abaixo do utilizado na indústria metalúrgica, ou seja, de apenas 0,02% do inoculante IM22. O suficiente para haver número mínimo de substratos para a grafita nuclear durante a solidificação. A condição de inoculação constante teve por objetivo destacar a influência dos elementos de liga estudados nas curvas de resfriamento, bem como nos parâmetros de solidificação. Os seguintes elementos foram adicionados ao metal base: selênio (0,2 a 0,5% em peso), níquel (0,2 a 0,5% em peso), ferro-fósforo (0,2 a 1,0% em peso), silício (0,05 a 0,4% em peso), chumbo (0,2 a 1,0% em peso) e estanho (0,2 a 0,8% em peso). Os pós destes elementos foram caracterizados por microscopia eletrônica de varredura (MEV) com microanálise química por dispersão de raios x (EDS). O metal base foi fundido em um forno de indução de média frequência, sendo sua composição característica de um ferro fundido cinzento de classe FC-25, corrigindo-se apenas o carbono e o silício. As amostras obtidas após a adição dos elementos de liga foram caracterizadas por microscopia óptica, espectrometria de emissão óptica e ensaios mecânicos de tração e dureza. Os resultados mostram que o selênio possui um forte efeito no super-resfriamento, favorecendo a formação de carbetos eutéticos. O níquel tende ao favorecimento da formação da grafita do tipo “A”. O fósforo tem o efeito de diminuir a resistência à tração do ferro fundido cinzento e promove a formação de “esteadita”. O silício favorece a formação da grafita do tipo “A”. O chumbo tem efeito deletério na morfologia da grafita. O estanho tem o efeito de aumentar as propriedades mecânicas. A utilização da técnica de análise térmica permitiu encontrar uma boa correlação entre os diversos parâmetros de solidificação estudados. Os resultados mostram que os elementos de liga atuam fortemente nas temperaturas do eutético estável e do eutético metaestável. Por fim, são propostas novas equações para o cálculo das temperaturas dos eutéticos estável e metaestável. As equações são baseadas nos resultados experimentais e nos dados do programa ATAS.
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24

Archambault, Damien. "Valorisation non alimentaire de l'huile de colza : pyrolyse de l'oléate de méthyle." Vandoeuvre-les-Nancy, INPL, 1997. http://www.theses.fr/1997INPL119N.

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Les esters méthyliques de l'huile de colza sont actuellement valorisés énergétiquement comme biocarburant. L’objectif de cette étude est de les valoriser chimiquement en alphaoléfines linéaires et en esters insaturés à chaine carbonée moyenne. Ces molécules à haute valeur ajoutée ont des débouchés importants dans les domaines des lubrifiants et des détergents biodégradables. Ce mémoire est divisé en deux parties : une étude expérimentale de la pyrolyse de l'oléate de méthyle et la modélisation de cette réaction. Nous avons pyrolysé dans un réacteur piston à pression atmosphérique l'oléate de méthyle dilué dans de l'azote ou dans de l'eau. La température de pyrolyse varie entre 500 et 700°C, le temps de passage entre 0,23 et 1,20 seconde et le taux de dilution est fixé à 10 moles de diluant par mole d'ester. Dans ces conditions, la pyrolyse conduit à la formation de méthane, d'éthylène, d'alphaoléfines linéaires de C3 à C18, d'esters méthyliques insaturés de C3:1 à C17:1, de monoxyde de carbone, de dioxyde de carbone, d'hydrogène et de coke. On forme également, en quantité plus faible, des paraffines linéaires, du benzène et du toluène. L’étude paramétrique a permis de définir le point de fonctionnement optimal du procédé pour la production de molécules à haute valeur ajoutée. Ce point se situe à une température de 600°C et pour des temps de passage compris entre 500 et 600 ms. La simulation à l'aide du code de calcul Chemkin d'un mécanisme radicalaire en chaine donne des résultats en accord avec les résultats expérimentaux obtenus à 600°C lors de la décomposition thermique de l'oléate de méthyle dilué dans l'azote. Pour permettre le dimensionnement d'un réacteur, un systeme d'équations stœchiométriques a été déterminé. Ce système rend compte de façon très satisfaisante de la conversion de l'oléate de méthyle et de la formation des produits.
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25

Esteves, Renata Antunes. "Influência da composição da matriz orgânica, conteúdo inorgânico e tratamento térmico sobre diferentes propriedades de compósitos experimentais." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/23/23140/tde-20022014-192449/.

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Objetivo: Analisar a influência da matriz orgânica, do conteúdo inorgânico e do tratamento térmico (TT) sobre diferentes propriedades de compósitos experimentais, tais como o grau de conversão (GC), tenacidade à fratura (KIC), resistência à flexão (RF) e módulo de elasticidade (ME). Métodos: Para o experimento foram analisadas seis formulações de compósitos experimentais com proporções molares de Bis-GMA:TEGDMA de 5:5 e 7:3, a carga utilizada foi o vidro de bário, nas concentrações de 30, 50 e 70% em peso, e os fotoiniciadores a amina e canforoquinona. O GC foi analisado através da espectroscopia no infra-vermelho (FTIR) (n=5). A KlC foi avaliada pelo método single-edge notched beam (SENB). As imagens das superfícies de fratura foram capturadas por um estereomicroscópio e a KlC calculada (n=10). A análise da RF e ME foi realizada através do teste dos três pontos (n=10). Para todos os fatores de variação estudados, metade dos espécimes imediatamente após à confecção receberam TT em estufa convencional, a 170º C por 10 minutos e a outra metade não. Após 24 horas, as amostras foram destinadas de acordo com os ensaios realizados. Os dados foram analisados utilizando ANOVA/Tukey para o grau de conversão, tenacidade à fratura e resistência à flexão, e, Kruskal-Wallis para o módulo de elasticidade (=5%). Resultados: Na análise do GC (%) foi observada significância estatística para os três fatores de variação analisados individualmente (monômero, carga e TT), como também, para a interação monômero x TT (p<0,001). Para a KIC e RF, as alterações significantes foram observadas apenas nos três fatores de variação (monômero, carga e TT) analisados individualmente (p<0,001). Para o ME, os fatores individuais (monômero, carga e TT), a interação carga x TT apresentaram significância estatística (p<0,001), bem como a interação monômero x carga (p=0,001). Conclusões: A matriz orgânica e o conteúdo inorgânico dos compósitos experimentais influenciaram o GC, a KIC, a RF e ME, e o TT promoveu melhorias nas propriedades estudadas.
Objective: To analyze the influence of organic matrix, the inorganic content and thermic treatment (TT) on different properties of experimental composites, such as the degree of conversion (DC), fracture toughness (KIC), flexural strength (FS) and elastic modulus (EM). Methods: This experiment analyzed six formulations of experimental composites with 5:5 and 7:3 molar proportions of Bis-GMA: TEGDMA. The load used was barium glass at concentrations of 30, 50 and 70% by weight and the photoinitiators, camphorquinone and amine. GC was analyzed by infrared spectroscopy (FTIR) (n=5). The KIC was evaluated by a \"single-edge notched beam\" (SENB). The images of the fracture surfaces were captured by a stereomicroscope and KIC calculated (n=10). The analysis FS and EM were performed by testing three points (n=10). For all the variation factors studied, half of the specimens immediately after the preparation received TT in conventional oven at 170º C for 10 minutes and the other half not. After 24 hours, the samples were designed according to the tests. Data were analyzed using ANOVA/Tukey the degree of conversion, fracture toughness and flexural strength, and Kruskal-Wallis test for the elastic modulus (=5%). Results: Analysis of GC (%) statistical significance was observed for the three variation factors analyzed individually (monomer, filler and TT), as well as for the interaction monomer x TT (p <0.001). For KIC and FS, significant changes were observed only in the three variation factors (monomer, filler and TT) analyzed individually (p<0.001). For EM, the individual factors (monomer, filler and TT) TT x filler interaction showed statistical significance (p <0.001), as well as the monomer x filler interaction (p = 0.001). Conclusions: The organic matrix and inorganic content of experimental composites influenced the GC, KIC, FS and EM, and the TT caused improvements in the properties studied.
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26

Ouarzki, Imane. "Production de bio-huile par pyrolyse de bois : application à la pré-séparation de la bio-huile." Thesis, Compiègne, 2015. http://www.theses.fr/2015COMP2194.

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Cette étude porte sur la production des bio-huiles à partir de la pyrolyse de bois de hêtre et celui du pin représentant respectivement les bois durs et les bois tendres. Afin de répondre à la problématique liée à la séparation des composés chimique de valeur ajoutée de la bio-huile,une étude a été effectuée sur la faisabilité d’une pré-séparation des constituants chimiques de la bio-huile à l’aide d’une pyrolyse étagée en température dans un réacteur en lit fixe de sorte à cibler la thermo-décomposition sélective des macro-composants de la biomasse (hémicellulose, cellulose et lignine). L’identification du couple macro-composant – marqueur de la décomposition est réalisée à partir du bilan en macro-composant dans le solide résiduel et l’identification par GC/MS des constituants contenus dans la bio-huile produite. Les résultats de cette partie ont montré la possibilité de la pré-séparation des fractions de dérivés de furane et des produits phénoliques, cependant le gain en sélectivité se fait au détriment du rendement total de la bio-huile. La deuxième partie de ce travail concerne l’étude de la production de la bio-huile dans les conditions de pyrolyse rapide dans un réacteur gaz/solide.Afin d’établir une relation entre les conditions opératoires de pyrolyse et la composition des bio-huiles, un outil permettant la comparaison pertinente des testes expérimentaux a été élaboré. Les expériences ont montré que le rendement de et la composition de l’huile de pyrolyse dépend essentiellement de : la nature du bois, la vitesse de chauffe et le temps de séjours effectif des particules de bois dans le réacteur
This research study is concerned in the production of bio-oils from the pyrolysis of beech and pines wood representing the hard and soft wood, respectively. In order to resolve the problems related to the separation of high added value molecules from the bio-oil, a study was held out on the feasibility of the pre-separation of the chemical components of bio-oil using of a staged pyrolysis temperature in a fixed bed reactor in order to target selective thermal decomposition of macro-components of biomass (hemicellulose, cellulose and lignin). The identification of macro-component couples - marker of decomposition is made from the balance macro-component in the residual solid and identification by GC / MS of the chemical components contained in the produced bio-oil. The results of this part have shown the possibility of the pre-separation of furans and phenolic derivatives, despite of the gain in selectivity at the expense of overall yield of bio-oil. The second part of this work (concerns with the study of the production of bio-oil in fast pyrolysis conditions in a gas / solid reactor. To establish a relationship between the operating conditions and chemical composition of pyrolysis bio-oil, a tool for meaningfull comparison of experiments was developed. Experiments have shown that the yield and composition of pyrolysis oil depends mainly on the composition of wood, the heating rate and the effective residence time of the wood particles into the reactor
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27

Šot, Petr. "Ověření tepelně-izolační vlastnosti termoreflexních fóliových izolací." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-226729.

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The master´s thesis deals with verification of thermal insulating property of thermoreflection foil insulations. The teoretical part of thesis focuses on the energy demand of buildings, the problems of heat transfer material, terms required for study of thermoreflection thermal insulation and experimental methods for determination of thermal insulating properties of insulators. In the next part the chapter is accompanied by an overview of the most common insulation materials which used in construction. The last part of teoretical part is devoted to the description of thermoreflect formation and analysis of the spread of thermal insulating layers of thermoreflection thermal insulation. The first part of thesis is devoted to the use of thermoreflection therm insulation in buildings. The second part of thesis is devoted to the design, assembly and calibration of the measuring device that uses a method of protected warm chamber. It is declared as a binding method of detection of the heat transfer performance of thermoreflection thermal insulation. The developed measuring device allows detection of endpoints in some direction of propagation of heat. Measurment of heat transfer coefficient devoted the third part of practical part. This part contains a description of the samples used for the measurement of the heat transfer coefficient. In the fourth chapter of the practical part are presented the results of the heat transfer coefficient measurments on selected samples of thermoreflection foil insulation. It is shown the characteristic of heat transfer coefficient of individual samples, the dependence of the heat transfer coefficient on the position of the sample in the measuring device and the recommendation of an appropriate use of sample in the works for the climatic conditions of the Czech republic. The work concludes the chapter of comparing and evaluating of all samples with practical recommendations.
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Baasch, Gaby. "Identification of thermal building properties using gray box and deep learning methods." Thesis, 2020. http://hdl.handle.net/1828/12585.

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Enterprising technologies and policies that focus on energy reduction in buildings are paramount to achieving global carbon emissions targets. Energy retrofits, building stock modelling, heating, ventilation, and air conditioning (HVAC) upgrades and demand side management all present high leverage opportunities in this regard. Advances in computing, data science and machine learning can be leveraged to enhance these methods and thus to expedite energy reduction in buildings but challenges such as lack of data, limited model generalizability and reliability and un-reproducible studies have resulted in restricted industry adoption. In this thesis, rigorous and reproducible studies are designed to evaluate the benefits and limitations of state-of-the-art machine learning and statistical techniques for high-impact applications, with an emphasis on addressing the challenges listed above. The scope of this work includes calibration of physics-based building models and supervised deep learning, both of which are used to estimate building properties from real and synthetic data. • Original grey-box methods are developed to characterize physical thermal properties (RC and RK)from real-world measurement data. • The novel application of supervised deep learning for thermal property estimation and HVAC systems identification is shown to achieve state-of-the-art performance (root mean squared error of 0.089 and 87% validation accuracy, respectively). • A rigorous empirical review is conducted to assess which types of gray and black box models are most suitable for practical application. The scope of the review is wider than previous studies, and the conclusions suggest a re-framing of research priorities for future work. • Modern interpretability techniques are used to provide unique insight into the learning behaviour of the black box methods. Overall, this body of work provides a critical appraisal of new and existing data-driven approaches for thermal property estimation in buildings. It provides valuable and novel insight into barriers to widespread adoption of these techniques and suggests pathways forward. Performance benchmarks, open-source model code and a parametrically generated, synthetic dataset are provided to support further research and to encourage industry adoption of the approaches. This lays the necessary groundwork for the accelerated adoption of data-driven models for thermal property identification in buildings.
Graduate
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29

Ming-HsuanGuo and 郭明軒. "Converting the Infrared Gray Thermal Image into Temperature Field to Detect the Defect inside Materials." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/50212286833240278726.

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30

Lan, Houng-Chih, and 藍宏智. "The Study of Thermal Comfort and Saving Energy on HVAC Using Gray Prediction with Fuzzy Control." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/53103574516518587614.

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碩士
國立彰化師範大學
工業教育學系
89
Heating, Ventilating and Air-conditioning (HVAC) is one of the requistite systems for modern life. It is an important issue to keep the indoor climate in a comfortable condition and save energy with a Variable-air-volume (VAV). The context about the acceptable operative temperature and humidity range for human body in typical summer time is referred to the ANSI/ASHRAE standard 55-1992 final report. This paper employs the Fuzzy Theory and Grey Theory to design a Grey Prediction with Fuzzy Control (GPFC), and the Enthalpy Theory to design a Least Enthalpy Estimator (LEE). Combining both the GPFC and LEE to process time delay and longer term effect of HVAC, it is easy to obtain optimal control strategy to balance between thermal comfort, energy saving and reliability.
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31

Chen, Kan-Cheng, and 陳淦政. "The Study of Thermal Properties on Environmentally Friendly Insulation Coating for Oyster-Shell-Powder’ Gray Surface Modification." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/16361233347289903555.

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Abstract:
碩士
明志科技大學
環境與安全衛生工程系環境工程碩士班
104
Use of waste oyster shell powder (OSP) replace titanium dioxide of pigments-fillers in the insulating coating, although having the dual advantages that assisted OSP to melt and reduce the cost of insulation coatings, However, when the OSP substituted titania ratio reaches a certain amount, Its original has good thermal properties such as surface cooling and albedo capacity will be significantly reduced. In other words, OSP substituted titania to modulate insulation coatings, insulation effect can play only at lower replacement rate conditions, so it is not conducive to large-scale use and to melt for waste OSP. Accordingly, in order to improve the OSP replacement rate for titanium dioxide and while maintaining good insulation properties, this study attempts to carry out series bleach of OSP, and the associated physical, chemical and thermal properties test in the laboratory and field environment, can improve the lot of OSP coatings due to lack of gray surface, as a reference to develop environmentally friendly insulation coating and improve its performance. It is expected to improve the missing of gray surface when a large number of OSP used in the coating, to serve as reference for future development of environmentally friendly insulation coating and improve its performance. Preliminary physics, chemistry experiment results showed that: (1)The use of Pantone swatches for visual comparison to hydrogen peroxide bleaching OSP’s gray improvement was better, and chlorine dioxide and sodium hypochlorite does not seem to increase surface brightness ability for oyster shell powder. (2)The variety trend of pH value for OSP bleaching, three ways to make the pH value showed increased reactivity, and to raise the pH of sodium hypochlorite is the most obvious because hydrolysis product NaOH(aq) production, reached alkali pH = 9.3. (3)The variety trend of chloride ion reaction for OSP bleaching, the chloride ion concentration presents a reduced phenomenon of using hydrogen peroxide, chlorine dioxide remains unchanged, while sodium hypochlorite is showing increased condition significantly due to salt crystallization after hydrolysis release large amounts of chloride ions and other factors. (4)The specific surface area and pore volume showed a downward trend for OSP bleaching, especially produces salt crystals reunited and clogging of sodium hypochlorite, has the lowest specific surface area and pore volume. (5)The bleaching of OSP by hydrogen peroxide or chlorine dioxide, the main ingredient is still CaCO3, did not produce a new generation of substance by X-ray diffraction spectroscopy, but the bleaching of OSP by sodium hypochlorite, whose composition is an increase in the reaction, such as NaCl crystals salt. (6)SEM image diagram of OSP shows that, OSP by calcination, its crystal image presents the appearance of a monomer structure, not as general OSP by grinding, showing the structure type of sheet stacked and rock chip, should be more conducive to the mixing paint, and (7)The results displayed by microwave digestion and TCLP, leaching of heavy metals for OSP were lower than the "Recognized standards for hazardous industrial waste " requirements, should be a feasibility on engineering applications. Moreover, preliminary results for the thermal properties are shown below: (1)The bleaching of OSP by hydrogen peroxide or chlorine dioxide have slightly lower heat conduction, but sodium hypochlorite has increased thermal conductivity due to the reason of lower the specific surface area and pore volume. (2)Indoor infrared illumination simulation results show that, for the coating by three bleached OSP to completely replace the titanium dioxide coating, have the ability to reduce the material surface and the room temperature, its surface reduced by up to 10 ℃, then only the indoor temperature drop within 1 ℃. This shows that OSP should be more biased in favor of a reflection type material, rather than type of insulation material. (3)OSP to completely replace the titanium dioxide coating, albedo ranged between 0.1 to 0.2 during the day, and OSP coatings bleached by hydrogen peroxide, albedo is increased to between 0.25~0.3, and (4)The use of simulation test house environment for field measurement results, the hydrogen peroxide bleaching OSP coating surface after cooling rate of up to about 6 ℃, and then the indoor temperature for the cooling effect is not found, but it can delay the internal temperature rise trend. Comprehensive test results of physical, chemical and thermal characteristics in laboratory and field conditions. Roof insulation coating of titanium dioxide with OSP completely replaced, it is recommended to conduct OSP bleaching by hydrogen peroxide, in the preparation and actual performance would be more feasible and practical value.
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