Dissertations / Theses on the topic 'Flat fan'

Recent attempts to utilise solid particles in combination with high pressure water sprays has caused environmental and safety concern, in cleaning mineral and organic scale inside the Oil and Gas Production Tubing. To increase cleaning performance only high pressure aerated water sprays at high impact force instead should be used. Multi-nationals petroleum companies are facing immense challenges in removing the scale due to the decrease in cavitation bubbles along the production tubing when high pressure water sprays are applied. This has also resulted in high maintenance costs and low productivity of the ‘wells’ with multi billions pounds financial losses per annum. Currently scales are removed using either aggressive chemicals (acids), complete replacement of the tubing, or solid-liquid sprays which are both expensive and causes environmental concern. This research demonstrated that the application of air-water combination (aerated sprays) are the solution in complete removal of various scales in the production tubing without the use of solid particles and the cavitation bubbles. This novel experimental technique of scale removal utilised air concentration (or aeration) in combination with high pressure flat fan sprays, of up to 10 MPa, at low flow rate (up to 12 l/min) with high impact pressure of approximately 0.15 MPa, in removing scale along production tubing using a simulated aeration chamber. It was found that varying air concentration from 3 to 12%, within the emulated chamber, improved scale erosion up to 28% higher than non-aerated technique. This enabled the mass of the scale to be removed at the ‘stand-off distance’ of 25 mm relative to scale samples, irrespective of cavitation bubble length suppression which is normally about 2 mm away from the atomiser orifice exit, compared to non-aerated techniques (solids and water). Scale erosion was found to be 12.80g, 7.31 g, and 65.80 g at aerated conditions compared to non-aerated provision which found to be 9.88g, 6.33g and 5.31 g, at the required liquid pressure 10 MPa, for the hard, medium and soft scale samples that are typically found in oil production tubing. Prior to scale removal trials sprays were characterised qualitatively and quantitatively under the ambient conditions as well as inside the aerated simulated chamber. Air velocities were found to be approximately 18m/s towards the water spray centre which then decays to 3 m/s towards the spray periphery under ambient conditions using hot wire anemometer. Moreover, the flat fan sprays were also characterised utilising Phase Doppler Anemometry (PDA). It was found that the high pressure water liquid droplet velocities were in the range of 75 to 117 m/s with droplet diameters of 55 to 81 µm (SMD) at flow rates of 7.6 to 11.3 l/min at various stand-off distances of 25, 50 and 75mm, providing an impact pressure of 0.05, 0.10 and 0.15 MPa respectively. Qualitatively cavitation bubble length was also estimated using high resolution imaging techniques which were found to be between 1 to 2 mm from the atomiser exit orifice under submerged conditions, at the stand-off distance ≤ 25 mm where the scale is normally removed. Beyond this range (1-2 mm) where the cavitation bubbles are not present, that are normally the benefactors to scale removal process, requires air concentration up to 12%. This ensures that a complete removal of the mass of corresponding scales to be achieved with varying chemical scale compositions. The air concentration is the ratio of total mass of air within the simulated chamber to mass of the liquid sprays impacting directly onto the scale samples. The results of the experimental trials were used to validate the available CFD fluent models with regards to spray dynamics, aerated air (velocities), cavitation bubble generations and scale erosion (removal). The sensitivity analysis using the CFD modelling gave close comparison with those obtained through experimental trials. Spray droplets size and their velocities were found to be within ±10% compared to those obtained via experimental findings. The aerated air velocities were also compared with the data generated from CFD which were found to be approximately ±9%. Furthermore, the cavitation bubble generation and the mass of the scale removed were found to vary within ±5% and ±7% respectively, when compared to the CFD data. Finding emerged that the spray droplets especially at the centre undergoes acceleration after primary breakup, which due to higher velocities resulting from the acceleration has left the entrained-air particles behind, which is characterise with substantially low-pressure region, giving rise to utilisation of the air-water interaction model. This could be another approach in further understanding the break regions within the high pressure liquid sprays.

Orientador: Ulisses Rocha Antuniassi
Resumo: Para uma aplicação de pesticidas com qualidade e segurança, é necessário a escolha adequada da ponta de pulverização, espectro de gotas e volume de calda. O objetivo dessa pesquisa foi avaliar a interação entre os formatos dos jatos de pulverização, com espectro de gotas similares e volumes de calda na cobertura nas folhas de soja. A pesquisa foi realizada na Faculdade de Ciências Agronômicas – UNESP/Botucatu e na Fazenda Fiorelli, Tejupá/SP. Para verificar se as pontas de pulverização utilizadas no ensaio possuíam o espectro de gotas similares, foi realizado um pré-ensaio, através da análise do espectro de gotas no analisador de partículas por imagem e em tempo real VisiSize Portable (Oxford Lasers Ltd/UK). A avaliação de cobertura das folhas foi conduzida em dois esquemas fatoriais 3x2, sendo um esquema fatorial utilizando as folhas do extrato superior da planta e outro no extrato médio/inferior e o delineamento em blocos casualisados, com cinco repetições. Os tratamentos foram compostos por três pontas de pulverização com formato do jato plano, jato plano duplo e jato plano angulado e dois volumes de caldas (100 e 200 L ha-1), na pressão de trabalho de 200 kPa. As caldas de pulverização foram preparadas utilizando o fungicida Sphere Max®, Aureo® e o corante Luxcor LRM 100. Para a avaliação da cobertura das folhas foram realizadas as aplicações no estádio R1 da soja, utilizando o pulverizador Columbia AD18, com velocidade de deslocamento de 7,8 e 3,9 km h-1 para os volumes ... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: For a pesticide application with quality and safety, it is necessary to choose the correctly spray nozzle, droplet spectrum and volume of spray solution. The aim of this research was to evaluate interaction between the spray nozzles shaped, with a similar droplet spectrum and volume of spray solution in the coverage in soybean leaves. The research was perform in the Faculdade de Ciências Agronômicas - UNESP/Botucatu and at Fazenda Fiorelli, Tejupá/SP. To verify if the nozzles used in the experiment had a similar droplet spectrum was carry out a pre-test, through the analysis of the droplet spectrum using the VisiSize Portable real-time particle analyzer. The evaluation of leaves coverage was conducted in two 3x2 factorial schemes, one factorial scheme using the leaves of the upper portion of a plant canopy and another in the medium/lower portion of a plant canopy and was use randomized block design, with five replications. The treatments consisted of three spray nozzles with different shaped: pre-orifice low drift flat fan, pre-orifice low drift double flat fan and angled flat fan and two volume of spray solution (100 and 200 L ha-1), at a working pressure of 200 kPa. The spray solutions were prepared using the mixture with Sphere Max® fungicide, Aureo® and Luxcor LRM 100 dye. For the evaluation of the leaves coverage, the applications were perform at the soybean R1 stage, using the Columbia AD18 sprayer, with the spray velocity of 7.8 and 3.9 km h-1 for the volume of spray s... (Complete abstract click electronic access below)
Mestre

This diploma thesis is a project of a two-storey building of a Kindergarten. The building will be used for educating preschool children. On the ground floor, there are two base classrooms, one in each wing of the building. Each classroom has several zones (relaxing, playing, creating). Each classroom also has its own dressing room, washroom + toilets. On the ground floor, we can also find facilities for teachers and the principal office. Since finished food will be delivered, the building only contains a food preparation facility + dry storage. The second floor is accessible either by stairs or by elevator. On the second floor, there is another base classroom with its own dressing room and a washroom with toilet. Food is transported from the first floor by elevator, which is not designed for transporting people. On the second floor, there is also the teacher´s base + large social hall for occasional events. The kindergarten building has an atypical layout. The building is partly roofed by a flat roof and partly by a gabled roof. The project was processed using the computer program AutoCAD. During processing, emphasis was placed on the correct layout, architectural design and safe use of the building.

A basin analysis was conducted at the Conway Flat coast (Marlborough Fault Zone, South Island, New Zealand) to investigate the interaction of regional and local structure in a transpressional plate boundary and its control on basin formation. A multi-tiered approach has been employed involving: (i) detailed analysis of sedimentary deposits; (ii) geomorphic mapping of terraces, fault traces and lineaments; (iii) dating of deposits by 14C and OSL and (iv) the integration of data to form a basin-synthesis in a sequence stratigraphy framework. A complex thrust fault zone (the Hawkswood Thrust Fault Zone), originating at the hinge of the thrust-cored Hawkswood anticline, is interpreted to be a result of west-dipping thrust faults joining at depth with the Hundalee Fault and propagating eastwards. The faults uplift and dissect alluvial fans to form terraces along the Conway Flat coast that provide the necessary relief to form the fan deltas. These terrace/fan surfaces are ~9 km long and ~3 km wide, composite features, with their upper parts representing sub-aerial alluvial fans. These grade into delta plains of Quaternary Gilbert-style fan deltas. Uplift and incision have created excellent 3D views of the underlying Gilbert-style fan delta complexes from topsets to prodelta deposits. Erosive contacts between the Medina, Rafa, Ngaroma and modern Conway fan delta deposits, coupled with changes in terrace elevations allow an understanding of the development of multiple inset terraces along the Conway Flat coast. These terraces are divided into five stages of evolution based on variations in sedimentary facies and geomorphic mapping: Stage I involves the uplift of the Hawkswood Range and subsequent increased sedimentation rate such that alluvial fans prograded to the sea to form the Medina fan delta Terrace. Stage II began with a period of incision, from lowering sea level or changes in the uplift and sedimentation rate and continued with the deposition of the Dawn and Upham fan deltas. Stage III starts with the incision of the Rafa Terrace and deposition of aggradational terraces in the upper reaches. Stage IV initiated by a period of incision followed by deposition of estuarine facies at ~8ka and Stage V began with a period of incision and continues today with the infilling of the incised valley by the modern fan delta of the Conway River and its continued progradation. New dates from within the Gilbert-type fan deltas along the Conway Flat coast are presented, using OSL and 14C dating techniques. Faulting at the Conway Flat coast began ~ 94 ka, based on the development of the Medina Terrace fan delta with uplift rates ~1.38~1.42 m/ka. The interplay of tectonics and sea level fluctuations continued as the ~79 ka Rafa Terrace fan deltas were created, with uplift rates calculated at ~1.39 m/ka. Detailed 14C ages from paleoforest (~8.4-~6.4 ka) in the Ngaroma Terrace and from the mouths of smaller streams have established uplift rates during the Holocene ~1-3 m/ka, depending on sea level.

This report examines the cross sections of silver microresonators subjected to an incident light with different polarization. The microresonators had different geometries with and without broken symmetries. Cross section profiles for different microresonator configurations are interesting for the division of Material Physics, Uppsala University, when designing metamaterials to tune the optical response of the material. The goal is to form an insight of how the optical response can be tuned by choosing different geometries, varying the size and polarization of the incident light. In this project computer simulations in COMSOL were made to simulate the optical response of different microresonators. When the incident light interact with the silver microresonators plasmonic excitations is generated which in turn interacts with the light changing the phase and therefore the optical response. By increasing the radius of the disk silver microresonantors the resonance was found to shift to lower energies. For a geometry with a disk microresonator inside a ring microresonator the Fano resonances were dependent of the radius of the disk microresonator.

La fragmentation des ions a charge piegee est un nouveau concept presente par m. Gross (lincoln, nebraska). Nous avons transpose ce concept au niveau analytique pour l'etude d'acide gras derives en ester de pentafluoro benzyle en generant d'une part des ions a charge piegee apres separation moleculaire en phase vapeur de ces esters (chromatographie en phase gazeuse), et d'autre part en les fragmentant successivement par collision dans une echelle de temps compatible avec la separation chromatographique. Cette methode tres sensible (nanogramme) a permis la determination structurale de nombreux acides gras nouveaux dans des extraits de mycobacteries. L'analyse de melanges par bombardement par atomes rapides (fab) est souvent incomplete par suite de rendements d'ionisation tres variables selon la nature des composes presents. Ainsi, nous avons songe a coupler l'ionisation fab a un processus de separation moleculaire de peptides en fonction de leur hydrophobicite (hplc phase inverse). L'association de la fab a flot continu et de la micro hplc a permis de caracteriser un variant d'une hemoglobine humaine (kohln) resultant d'une mutation ponctuelle. Sa detection n'avait pu etre realisee par la methode classique du fab statique. Cette nouvelle methode est beaucoup plus sensible et permet des analyses dans le domaine de la picomole

Dissertação de Mestrado em Engenharia Zootécnica/Produção Animal
Atualmente, a nível mundial, configura-se a perspetiva de um aumento de consumo de insetos tanto pelos humanos como pelos animais, pelo que se considera importante a realização de diferentes estudos, nomeadamente da sua utilização nas dietas animais. Com o objetivo de comparar o efeito do uso de duas gorduras suplementadas na dieta de coelhos, nomeadamente de origem animal e vegetal (óleo de Hermetia illucens, e de linho, respetivamente), foram formulados 4 regimes alimentares com teor baixo (5%) e com teor alto (8%) de gordura, para cada fonte de gordura adicionada, e distribuídos a 48 coelhos (12 x 4) com 35 dias (recém desmamados) alojados em gaiolas de digestibilidade. Os animais tiveram acesso ad libitum a alimento e água durante as 5 semanas do perído experimental, sendo abatidos aos 70 dias de idade. Foram avaliados os resultados zootécnicos, sem diferenças significativas (P>0,05) e recolhidas e analisadas as fezes na 4ª semana do ensaio, para se avaliar a digestibilidade aparente das dietas. Os pesos iniciais (1047g) foram uniformes e os finais (2405g) foram semelhantes em todos os grupos. Verificou-se que há um efeito muito significativo na natureza da gordura (P<0,0001), na digestibilidade da matéria seca e na da matéria orgânica. Os regimes com óleo de insetos têm uma digestibilidade da MS e da MO cerca de 95% da digestibilidade das mesmas frações dos regimes com óleo de linho. Também a digestibilidade das frações EE e EB foi significativamente mais baixa (P<0,05) nos regimes com óleo de inseto. Os regimes com teores de gordura mais altos aumentaram a digestibilidade (P<0,0001) do extracto etéreo, mas diminuíram (P<0,003) a digestibilidade da celulose. Foram analisadas as carcaças, e não houveram diferenças significativas (P>0,05) nos pesos do aparelho digestivo, fígado, gorduras peri-renal e inter-escapular, apenas um efeito no peso do estômago vazio (P=0,006), maior nos regimes com óleo de insetos, provavelmente devido a uma maior retenção de alimento durante o período experimental. Entre os resultados colorimétricos obtidos, não parecem haver diferenças significativas, excepto uma tonalidade mais vermelha na carne dos animais dos regimes com óleo de insetos (P=0,047). De acordo com estes resultados a gordura de insetos pode ser utilizada na alimentação do coelho, apenas com alguma perda na digestibilidade da matéria seca e orgânica, mas não afetando o crescimento nem o rendimento da carcaça.
ABSTRACT - Use of alternative foods in the rabbit diet: insect oil vs flax oil - Currently, the world-wide perspective is an increase in the consumption of insects by both humans and animals. Therefore, it is considered important to carry out different studies including their use in animal diets. In order to compare the effect of two fat supplements on the rabbit diet, from animal and vegetable origin (Hermetia illucens oil, and flax/lindseed oil, respectively), four dietary regimens with low (5%) and high (8%) fat content, for each fat souce added, and distributed to 48 rabbits (12 x 4) with 35 days of age (recently weaned) housed in digestibility cages. The animals had access ad libitum to food and water during the 5 weeks of the experimental period, being slaughtered at 70 days of age. The zootechnical results were evaluated, without significant differences (P> 0.05) and feces were collected in the 4th week oh the trial, and analyzed to evaluate the apparent digestibility of the diets. The initial weights (1047g) were uniform and the final weights (2405g) were similar in all groups. It was verified that there is a very significant effect on the nature of fat (P <0.0001), on dry matter and organic matter digestibility. Insect oil regimes have a digestibility of DM and OM about 95% of the digestibility of the same fractions from flax oil regimes. Also, the digestibility of the EE (ethereal extract) and GE (gross energy) fractions were significantly lower (P <0.05) in the insect oil regimens. Regimens with higher fat contents increased the digestibility (P <0.0001) of ethereal extract, but decreased (P <0.003) the cellulose digestibility. Carcasses were analyzed, and there were no significant differences (P> 0.05) in digestive tract, liver, peri-renal and inter-scapular fat weights, only an effect on empty stomach weight (P = 0.006), higher in insect oil regimes, probably due to higher feed retention during the experimental period. Among the colorimetric results obtained, there appear to be no significant differences, except for a reddish in meat of the animals who ate insect oil regimes (P = 0.047). According to these results, insect fat can be used on rabbit diet, with only some slightly lower digestibility in dry matter and organic matter, but not affecting the growth or carcass yield.
N/A

The subject of this thesis is the taxation of the estate owner. The content of the project is firstly identification with the general tax patterns, thereinafter theoretical analysis of the introduced issues and finally its application on the concrete company. The study should give compact view on the tax liability, as a result of the ownership of the estate.

碩士
國立臺北科技大學
車輛工程系所
100
This study presents the thermal and flow characteristic of flat-plate heat sink in rectangular channel with piezoelectric fan by using numerical method with CFD software Fluent. A piezoelectric fan is an attractive device to remove heat from microelectronic due to it’s low power consumption, minimal noise and compactness. By vertical arrangement, It is found that heat the heat transfer augmentation of the piezoelectric fan comes from the entrained airflow during each oscillation cycle and the jet air stream at the fan tip. The parameters are discussed in detail, such as Nusselt number(Nu), distance between piezoelectric fan to heat sink(Lg), distance between center of piezoelectric fan to channel’s bottom(Hw), including the (Single-fan) and (Twin-fan) with (Counter phase) and(In phase), A volumetric coefficient of performance is also proposed. The heat transfer performance for vertical arrangement.

碩士
國立高雄應用科技大學
模具工程系
103
The cooling effect of the dual-pressure fan has been investigated in this study. The experiment was performed by a driving force of 110V and 60Hz, at a fixed amplitude range of the piezoelectric fan. A 6 cm × 6 cm heating sheet was utilized as a heating source, above which pure cooper was applied as the heating surface. Temperature was measured by 9 thermocouples placed 0.5 cm distance below the heating surface. The mutual distance between (H) two blades of the dual-piezoelectric fans were varied from 0 to 1 (H/L=0, 0.25, 0.5, 0.75, 1).The heating surface was placed vertically or horizontally, and edge to edge distance (D*) of the dual-piezoelectric fans was varied from 0 to 1 (0,0.33,0.66,1).To analyze the nature convection between the heating plate and the heat radiation of the dual-piezoelectric fans, a variation of placement modes (vertical or horizontal) between two blades of the dual-piezoelectric fans and the heating sheet has been studied. As the surface of radiant heater becomes larger, When the level of resistance increases with the penetration depth H* decreases, the vertical and horizontal contrast, the thermal resistance increases with the depth of invasion, the best and worst resistance horizontal furnishings difference was 11.94%, 18.76% for the vertical.. When the dual-piezoelectric fans placed vertically in edge to edge distance, the cooling effect became better as the fans far away from each other. However,the thermal resistance increased when the distance between the dual-piezoelectric fans and the heating block increased. On the other hand, the cooling effect reduced when the dual-piezoelectric fans placed horizontally in edge to edge distance. As the dual-piezoelectric fans were too far away from each other, there was no airflow to enhance the cooling effect. The thermal resistance revealed no reverse result while edge to edge distance D* = 0. Nevertheless, the result obtained from edge to edge distance D* = 1 demonstrated that edge to edge dual-piezoelectric fans interaction leads to H* = 1 improve thermal resistance.