Academic literature on the topic 'Exergy analysis'
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Journal articles on the topic "Exergy analysis"
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Chauhan, Tejasvi, and Vinod Gaur. "Exergy Analysis." Ecology, Economy and Society–the INSEE Journal 6, no. 1 (2023): 31–51. http://dx.doi.org/10.37773/ees.v6i1.914.
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This paper argues for a continuing exploration of Nature’s organizing principles that sustain prolonged homeostasis of the earth’s ecosystems punctuated by forceful transitions to new emergent states. Ecosystems develop and maintain a dynamically stable state by transacting energy and materials with the surrounding flows to keep reversing their continual fall to the ground state. Conversely, the elevation of any component of the ecosystem above the ground level may be regarded as a measure of its functional efficiency. This measure, called exergy, can be calculated for an eco-subsystem based on knowledge of the energy and material fluxes that thread it and, most importantly, of where the ground level happens to be. Admittedly, it is not straightforward to quantify these figures, and the departure of assumptions from reality will inevitably translate into errors in the calculated exergy figures. However, the variance may be estimated by analysing the results of an ensemble...
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Alibaba, Massomeh, Razieh Pourdarbani, Mohammad Hasan Khoshgoftar Manesh, Israel Herrera-Miranda, Iván Gallardo-Bernal, and José Luis Hernández-Hernández. "Conventional and Advanced Exergy-Based Analysis of Hybrid Geothermal–Solar Power Plant Based on ORC Cycle." Applied Sciences 10, no. 15 (2020): 5206. http://dx.doi.org/10.3390/app10155206.
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Today, as fossil fuels are depleted, renewable energy must be used to meet the needs of human beings. One of the renewable energy sources is undoubtedly the solar–geothermal power plant. In this paper, the conventional and advanced, exergo-environmental and exergo-economic analysis of a geothermal–solar hybrid power plant (SGHPP) based on an organic Rankin cycle (ORC) cycle is investigated. In this regard, at first, a conventional analysis was conducted on a standalone geothermal cycle (first mode), as well as a hybrid solar–geothermal cycle (second mode). The results of exergy destruction for simulating the standalone geothermal cycle showed that the ORC turbine with 1050 kW had the highest exergy destruction that was 38% of the total share of destruction. Then, the ORC condenser with 26% of the total share of exergy destruction was in second place. In the hybrid geothermal–solar cycle, the solar panel had the highest environmental impact and about 56% of the total share of exergy destruction. The ORC turbine had about 9% of all exergy destruction. The results of the advanced analysis of exergy in the standalone geothermal cycle showed that the avoidable exergy destruction of the condenser was the highest. In the hybrid geothermal–solar cycle, the solar panel, steam economizer and steam evaporator were ranked first to third from an avoidable exergy destruction perspective. The avoidable exergo-economic destruction of the evaporator and pump were higher than the other components. The hybrid geothermal–solar cycle, steam economizer, solar pane and steam evaporator were ranked first to third, respectively, and they could be modified. The avoidable exergo-environmental destruction of the ORC turbine and the ORC pump were the highest, respectively. In the hybrid geothermal–solar cycle, steam economizers, solar panel and steam evaporators had the highest avoidable exergy destruction, respectively. For the standalone geothermal cycle, the total endogenous exergy destruction and exogenous exergy destruction was 83.61% and 16.39%. Moreover, from an exergo-economic perspective, 89% of the total destruction rate was endogenous and 11% was exogenous. From an exergo-environmental perspective, 88.73% of the destruction rate was endogenous and 11.27% was exogenous. For the hybrid geothermal–solar cycle, the total endogenous and exogenous exergy destruction was 75.08% and 24.92%, respectively. Moreover, 81.82% of the exergo-economic destruction rate was endogenous and 18.82% was exogenous. From an exergo-environmental perspective, 81.19% of the exergy destruction was endogenous and 18.81% was exogenous.
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Mora, C. B. H., and S. De Oliveira Jr. "ENVIRONMENTAL EXERGY ANALYSIS OF WASTEWATER TREATMENT PLANTS." Revista de Engenharia Térmica 5, no. 2 (2006): 24. http://dx.doi.org/10.5380/reterm.v5i2.61848.
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This work evaluates the environmental impact of Wastewater Treatment Plants (WTP) based on data generated by the exergy analysis, calculating and applying environmental impact indexes for two WTP located in the Metropolitan Area of São Paulo. The environmental impact of the waste water treatment plants was done by means of evaluating two environmental impact exergy based indexes: the environmental exergy efficiency (ηenv,exerg) and the total pollution rate (Rpol,t). The environmental exergy efficiency is defined as the ratio of the exergy of the useful effect of the WTP to the total exergy consumed by human and natural resources, including all the exergy inputs. That relation is an indication of the theoretical potential of future improvements of the process. Besides the environmental exergy efficiency, it is also used the total pollution rate, based on the definition done by Makarytchev (1997), as the ratio of the destroyed exergy associated to the process wastes to the exergy of the useful effect of the process. The analysis of the results shows that this method can be used to quantify and also optimise the environmental performance of Wastewater Treatment Plants.
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Le Goff, P., and J. M. Hornut. "Exergy Analysis and Exergo-Economic Optimization of Industrial Processes." Revue de l'Institut Français du Pétrole 53, no. 1 (1998): 99–102. http://dx.doi.org/10.2516/ogst:1998011.
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Kotas, T. J., Y. R. Mayhew, and R. C. Raichura. "Nomenclature for Exergy Analysis." Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 209, no. 4 (1995): 275–80. http://dx.doi.org/10.1243/pime_proc_1995_209_006_01.
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In this paper a system of names and symbols for exergy analysis is put forward for further discussion. The concept of exergy is shown to be dependent on that of the environment. The conceptual environment provides a natural reference state for calculating absolute values of exergy. For calculating loss of exergy, or process irreversibility, an exergy balance or the Gouy–Stodola relation can be used. The concept of chemical exergy can facilitate the computational work involved in exergy analysis. The paper offers a glossary of terms used in exergy analysis and shows the proposed symbols in the context of expressions in which they might be used.
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Kallio, Sonja, and Monica Siroux. "Exergy and Exergy-Economic Approach to Evaluate Hybrid Renewable Energy Systems in Buildings." Energies 16, no. 3 (2023): 1029. http://dx.doi.org/10.3390/en16031029.
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Hybrid renewable energy systems (HRES) combine two or more renewable energy systems and are an interesting solution for decentralized renewable energy generation. The exergy and exergo-economic approach have proven to be useful methods to analyze hybrid renewable energy systems. The aim of this paper is to present a review of exergy and exergy-economic approaches to evaluate hybrid renewable energy systems in buildings. In the first part of the paper, the methodology of the exergy and exergo-economic analysis is introduced as well as the main performance indicators. The influence of the reference environment is analyzed, and results show that the selection of the reference environment has a high impact on the results of the exergy analysis. In the last part of the paper, different literature studies based on exergy and exergo-economic analysis applied to the photovoltaic-thermal collectors, fuel-fired micro-cogeneration systems and hybrid renewable energy systems are reviewed. It is shown that the dynamic exergy analysis is the best way to evaluate hybrid renewable energy systems if they are operating under a dynamic environment caused by climatic conditions and/or energy demand.
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Malik, F. Elmzughi, I. Dekam Elhadi, G. Almuzwghi Ali, and Seddig Khaled. "Exergoeconomic analysis and parametric investigation of a gas turbine power plant." i-manager's Journal on Power Systems Engineering 10, no. 1 (2022): 1. http://dx.doi.org/10.26634/jps.10.1.18827.
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Thermoeconomic models, combining the concept of cost in economics and the concept of exergy in thermodynamics, provide the ability to optimize complex power generation systems to achieve the best balance between thermodynamic efficiency and economic cost. In this paper, a parametric analysis was carried out based on the method of calculating the unit exergy cost, as well as exergo-economic studies and cost sensitivity studies on the exergy of the cycle of a gas turbine power plant. The mathematical models of mass, energy, effort, and economy were created and presented. Thermodynamic properties and research analysis are performed using the MINI- REFerence fluid PROPerties (MINI-REFPROP) and matrix laboratory (MATLAB) SIMULINK software packages. The analysis leads to valuable benchmarks of the economic situation. The exergo-economic coefficient, the total cost of exergy loss, exergy destruction for the combustion chamber, and labor productivity are determined. When conducting parametric studies, the influence of the temperature at the inlet to the gas turbine, the temperature at the inlet to the air compressor, and the degree of pressure increase in the compressor were taken into account. The combustion chamber at the plant was found to have the highest energy destruction rate of 80%, indicating that boilers need to be given more attention in terms of design, selection, operation, and maintenance. However, in percentage terms, the combustion chamber has a high improvement potential of 94%. Sensitivity and parametric analysis show that while the exergy factor, the total cost of exergy loss, exergy destruction for the combustion chamber, and power output fall with increasing air compressor inlet temperature, it can be increased with increasing compressor pressure ratio. The total energy loss cost, combustor energy loss, and power output decrease as the gas turbine inlet temperature rises, while the cycle network and overall exergy destruction rate increase. The rates of the exergy destruction of the Venture Capital (VC), the combustion chamber of the combustion chamber, and the total exergy destruction are 25.2, 122.3, and 153.2 MW, respectively, for the proposed conditions. In addition, the results showed that it was $2,272 per hour, while the cost of work performed in energy terms is $1,769 per hour with a fuel cost of $0.003 per MJ. A valuable achievement is the availability of defined values and clear parametric influences, which can be of great help to engineers and site operators in the efficient execution of unique tasks, playing with the conflicts of energy use, exergy, and cost.
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MATSUBARA, Yoichi. "Fundamentals of Exergy Analysis." TEION KOGAKU (Journal of Cryogenics and Superconductivity Society of Japan) 29, no. 5 (1994): 165–73. http://dx.doi.org/10.2221/jcsj.29.165.
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Latypov, A. F. "Exergy analysis of ramjet." Thermophysics and Aeromechanics 16, no. 2 (2009): 303–13. http://dx.doi.org/10.1134/s0869864309020152.
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Pavelka, Michal, Václav Klika, Petr Vágner, and František Maršík. "Generalization of exergy analysis." Applied Energy 137 (January 2015): 158–72. http://dx.doi.org/10.1016/j.apenergy.2014.09.071.
Full textDissertations / Theses on the topic "Exergy analysis"
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KHEDR, SOBHY YEHIA MOHAMMED. "Exergy and Exergy Cost Analysis of production systems incorporating renewable energy sources." Doctoral thesis, Università degli Studi di Trieste, 2022. http://hdl.handle.net/11368/3030491.
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Exergy is a thermodynamic quantity capable of measuring the conversion of material and energy flows into comparable terms based on the capacity of such flows to generate mechanical work as a useful effect and identifying and quantifying the thermodynamic inefficiencies of a generic process by means of the exergy destruction term.
Because of its properties, an exergy is a convenient tool for the calculation of the global resource consumption of both natural and engineering processes. Therefore, there are different exergy-based approaches. Every exergy-based approach has its advantages and its drawbacks. It even has its own spatial and temporal domain [1].
There are different exergy-based approaches that have been reviewed which are EMergy, Extended Exergy, Cumulative Exergy Consumption, Exergetic life cycle assessment, and Thermoeconomics. Reviewing different exergy approaches, especially the approaches that introduce the externalities like Labour, Capital, and environmental cost with their equivalent exergy values will help to develop an approach that avoids the drawbacks and take advantage of other approaches.
Exergy-based account methodologies do not account for the ecological processes and products. This is something savior if sustainability is the aim and the goal. The indirect cost of resource consumption must be counted. The exergy cost of mineral resources which are not renewable is not their chemical exergy embodied in them only but also the cost of exergy that has been to be spent to reconcentrate these resources to be available for the upcoming generations [2]. As it is a matter of sustainability, considering the indirect exergy cost is very important.
Each exergy-based methodology has its own spatial and temporal boundary. Some of them account only for the exergy consumed during the operation phase like the basic exergy analysis and some of them extend its spatial boundary to include the ecological cumulative exergy cost of a specific product [3]. The ecological cumulative exergy consumption ECEC approach has been introduced by Szarjut. Another approach extends its spatial boundary including the economy of the region or a country where the analysis takes place. This allows some other externalities like money and labor to be accounted in form of exergy. This approach is the extended exergy analysis EEA.
This thesis presents a conceptual development of sustainability evaluation, through an exergy-based Indicator, by using the new concept of the Thermoeconomic Environment (TEE). The exergy-based accounting methods here considered as a background are the Extended Exergy Accounting (EEA), which can be used to quantify the exergy cost of externalities like labor, monetary inputs, and pollutants, and the Cumulative Exergy Consumption (CExC), which can be used to quantify the consumption of primary resources “embodied” in a final product or service. Also, the new concept of bioresource stock replacement cost is presented, highlighting how the framework of the TEE offers an option for evaluating the exergy cost of products of biological systems. The sustainability indicator is defined based on the exergy cost of all resources directly and indirectly consumed by the system, the equivalent exergy cost of all externalities implied in the production process and, the exergy cost of the final product.<br>Exergy is a thermodynamic quantity capable of measuring the conversion of material and energy flows into comparable terms based on the capacity of such flows to generate mechanical work as a useful effect and identifying and quantifying the thermodynamic inefficiencies of a generic process by means of the exergy destruction term.
Because of its properties, an exergy is a convenient tool for the calculation of the global resource consumption of both natural and engineering processes. Therefore, there are different exergy-based approaches. Every exergy-based approach has its advantages and its drawbacks. It even has its own spatial and temporal domain [1].
There are different exergy-based approaches that have been reviewed which are EMergy, Extended Exergy, Cumulative Exergy Consumption, Exergetic life cycle assessment, and Thermoeconomics. Reviewing different exergy approaches, especially the approaches that introduce the externalities like Labour, Capital, and environmental cost with their equivalent exergy values will help to develop an approach that avoids the drawbacks and take advantage of other approaches.
Exergy-based account methodologies do not account for the ecological processes and products. This is something savior if sustainability is the aim and the goal. The indirect cost of resource consumption must be counted. The exergy cost of mineral resources which are not renewable is not their chemical exergy embodied in them only but also the cost of exergy that has been to be spent to reconcentrate these resources to be available for the upcoming generations [2]. As it is a matter of sustainability, considering the indirect exergy cost is very important.
Each exergy-based methodology has its own spatial and temporal boundary. Some of them account only for the exergy consumed during the operation phase like the basic exergy analysis and some of them extend its spatial boundary to include the ecological cumulative exergy cost of a specific product [3]. The ecological cumulative exergy consumption ECEC approach has been introduced by Szarjut. Another approach extends its spatial boundary including the economy of the region or a country where the analysis takes place. This allows some other externalities like money and labor to be accounted for in form of exergy. This approach is the extended exergy analysis EEA.
This thesis presents a conceptual development of sustainability evaluation, through an exergy-based Indicator, by using the new concept of the Thermoeconomic Environment (TEE). The exergy-based accounting methods here considered as a background are the Extended Exergy Accounting (EEA), which can be used to quantify the exergy cost of externalities like labor, monetary inputs, and pollutants, and the Cumulative Exergy Consumption (CExC), which can be used to quantify the consumption of primary resources “embodied” in a final product or service. Also, the new concept of bioresource stock replacement cost is presented, highlighting how the framework of the TEE offers an option for evaluating the exergy cost of products of biological systems. The sustainability indicator is defined based on the exergy cost of all resources directly and indirectly consumed by the system, the equivalent exergy cost of all externalities implied in the production process and, the exergy cost of the final product.
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Wills, James Alexander. "Exergy analysis of a Stirling cycle." Master's thesis, University of Cape Town, 2017. http://hdl.handle.net/11427/26865.
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In this dissertation the analysis of the Stirling engine is presented, this research topic falls within the category of thermal energy conversion. The research that was conducted is presented in three chapters of which the topics are: the effects of allocation of volume on engine performance, the GPU-3 (Ground Power Unit - developed by GM) Stirling engine analysis, and the optimisation of a 1000 cm³ Stirling engine with finite heat capacity rates at the source and the sink. The Stirling engine has many advantages over other heat engines, as it is extremely quiet, has multi-fuel capabilities and is highly efficient. There is also significant interest in using Stirling engines in low to medium temperature solar thermal applications, and for waste heat recovery. To develop high-performance engines that are also economically viable, advanced mathematical models that accurately predict performance and give insight into the different loss mechanisms are required. This work aims to use and adapt such a model to analyse the effects of different engine parameters and to show how such a model can be used for engine optimisation using the Implicit Filtering algorithm. In the various analyses that are presented, the dynamic second order adiabatic numerical model is used and is coupled to equations that describe the heat and mass transfer in the engine. The analysis shows that the allocation of volume has a significant effect on engine performance. It is shown that in high-temperature difference (HTD) engines, increasing dead-volume ratio increases efficiency and decreases specific work output. In the case of low-temperature difference (LTD) and medium-temperature difference (MTD) engines, there is an optimal dead-volume ratio that gives maximum specific work output. It was also found that there are optimal swept volume ratios and that the allocation of heat exchanger volume has a negligible effect on engine performance - so long as the dead-volume ratio is optimal. The second order model with irreversibilities included was used to perform an exergy analysis of the GPU-3 Stirling engine. This model compared well with experimental results and the results from other models found in the literature. The results of the study show the two different approaches in modelling the engine losses and the effect that the various engine parameters have on the GPU-3 power output and efficiency. The optimisation of the 1000 cm³ Stirling engine was performed using a model with finite heat capacity rates at the source and the sink, fixed number of heater and cooler tubes, and four different regenerator mesh types. The engine geometry was optimised for maximum work output using the implicit filtering algorithm, and the results show the dominant effect that the regenerator has on engine performance and the geometry that gives maximum work output. The critical insights obtained from this research are the importance of the dead-volume ratio in engine analysis, the merits of the novel Second law Stirling engine model, and the importance of regenerator mesh choice and geometry. The Implicit filtering algorithm is also shown to be a suitable choice of optimisation algorithm to use with Stirling engine mathematical models.
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Ramírez, Ibaceta Sebastián Eduardo. "Exergy analysis of the chilean society." Tesis, Universidad de Chile, 2017. http://repositorio.uchile.cl/handle/2250/146760.
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Ingeniero Civil en Biotecnología<br>The present report contains an exergy analysis of the Chilean society in 2013. Wall s approach was taken to assess the exergy efficiency of four main economic sectors: mining, manufacturing, transportation, and households.
Several assumptions were taken to simplify the complex thermodynamic interactions within the society model. For instance, exergy flows among economic sectors were not considered, due to the lack of relevant statistical data on these interactions. On the other hand, only some of the exergy carriers entering and leaving the society were accounted, as the focus of this work is to provide a first outlook of the Chilean exergy efficiency from a chemical exergy standpoint. An extended exergy analysis (EEA) is proposed for future studies, in order to integrate exergy of labor and capital into the analysis. Statistical power plays an important role in this matter, as key data required to perform an EEA is nowadays unavailable.
The efficiency of the society in 2013 was 24%. Comparing with other societies, the Chilean case was found to be in between advanced economies and less developed countries. The current development model is criticized, as the most developed countries previously analyzed have the lowest thermodynamic efficiency. In the long term, a shift of paradigm is expected, fostering local development and educating about resources overconsumption. Regarding Chilean economic sectors, exergy efficiency was found to be higher in extractive activities, such as mining (53%), and manufacturing (53%). In general, exergy efficiency was lower in services and end-use sectors, such as transportation (21%), and households (10%). This is considered to be related with omission of labor in the analysis, as end-use sectors show a higher dependency on human work compared to industrial/extractive activities.
Despite of methodological difficulties, interesting suggestions were obtained from the analysis. Structural changes are proposed in the manufacturing sector, to improve the efficiency of transformations carried out in agriculture, livestock, and aquaculture activities. Food industry as a whole would improve its thermodynamic performance if steps in this direction were taken. Likewise, fostering a technological shift towards electric vehicles would imply a much better use of the available resources. In the same way, improvements in water and space heating are desirable, as these two end-uses are the most exergy intensive applications in household consumption.
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Colpan, Can Ozgur. "Exergy Analysis Of Combined Cycle Cogeneration Systems." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12605993/index.pdf.
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In this thesis, several configurations of combined cycle cogeneration systems proposed by the author and an existing system, the Bilkent Combined Cycle Cogeneration Plant, are investigated by energy, exergy and thermoeconomic analyses. In each of these configurations, varying steam demand is considered rather than fixed steam demand. Basic thermodynamic properties of the systems are determined by energy analysis utilizing main operation conditions. Exergy destructions within the system and exergy losses to environment are investigated to determine thermodynamic inefficiencies in the system and to assist in guiding future improvements in the plant. Among the different approaches for thermoeconomic analysis in literature, SPECO method is applied. Since the systems have more than one product (process steam and electrical power), systems are divided into several subsystems and cost balances are applied together with the auxiliary equations. Hence, cost of each product is calculated. Comparison of the configurations in terms of performance assessment parameters and costs per unit of exergy are also given in this thesis.
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Twort, Charles Tyler. "An exergy analysis of mine cooling systems." Thesis, University of Nottingham, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323333.
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Molinari, Marco. "Exergy Analysis in Buildings : A complementary approach to energy analysis." Licentiate thesis, KTH, Civil and Architectural Engineering, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-11537.
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<p>Though mandatory to be pursued, improved energy efficiency is not the only target to reach. The quality of energy has to be assessed as well. Most of the overall energy use in residential building is for low temperature heat, i.e. temperatures relatively close to the outdoor conditions. From a thermodynamic point of view, this is a degraded form of energy with low potential to be converted into work. On the other hand energy demand is mostly met with high quality energy, such as electricity and natural gas. There is a mismatch between supply and demand, which is not clearly shown by the sole energy analysis. Target of this thesis is to analyze the energy use in buildings from the point of view of its quality, to provide effective theoretical and calculation tools to investigate this mismatch, to assess its magnitudo and to propose improvements aiming at a more rational use of the energy. The idea behind the quality is clarified with the concept of exergy.</p><p>The potential for improvement in space heating is shown. In no heating system the overall exergy efficiency is above 20%, with fossil fuels. Using direct electricity heating results in exergy efficiency below 7%. Most of the household appliances processes have low-exergy factors but still are supplied with electricity. This results in poor exergy efficiencies and large exergy losses.</p><p>Systems are poorly performing because little consideration is explicitly given to energy quality. Policies to lower the energy demand, though vital as first step towards an improved use of energy, should not neglect the exergy content.</p><p>The problem is then shifted to find suitable supplies. Electricity can be exploited with low exergy losses with high-COP heat pumps. Use of fossil fuels for heating purposes should be avoided. District heating from cogeneration and geothermal proves to be a suitable solution at the building level. The issues connected to its exploitation forces to shift the boundary layers of the analysis from the building level to the community level. A rational use of energy should address the community level. The system boundaries have to be enlarged to a dimension where both the energy conversion and use take place with reduced energy transportation losses. This is a cost-effective way to avoid the waste of the exergy potential of the sources with exergy cascade and to make it possible the integration of with renewable sources. Exergy efficiency of the buildings is a prerequisite for a better of energy in this field.</p><br>IEA ECBCS Annex 49: Low Exergy Systems for High Performance Buildings and Communities<br>ESF Cost C24: Analysis and Design of Innovative Systems for Low-EXergy in the Built Environment: COSTeXergy
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Mady, Carlos Eduardo Keutenedjian. "Desempenho termodinâmico do corpo humano e seus subsistemas: aplicações à medicina, desempenho esportivo e conforto térmico." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/3/3150/tde-21102014-110723/.
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A análise exergética é aplicada ao ser humano para avaliar a qualidade dos processos de conversão de energia no corpo e seus sistemas, assim como nos processos bioquímicos do metabolismo. Sabe-se que a vida tem um início, um desenvolvimento e um fim, ou seja, um típico exemplo de processo irreversível. Como tanto a idade cronológica como a entropia gerada são grandezas positivas (caminham no mesmo sentido), esta última passa a ser denominada de flecha do tempo (arrow of time). Assim, a partir da aplicação da Segunda Lei da Termodinâmica, torna-se possível desenvolver e aplicar índices baseados no conceito de exergia destruída/entropia gerada e rendimento exergético para diferentes áreas do conhecimento como medicina (comparação de técnicas de hipotermia), esportes (teste ergoespirométrico) e engenharia (conforto térmico). Para tal, propõe-se um modelo do corpo humano que leva em conta a transferência de exergia para o ambiente, a qual é causada pela radiação, convecção, vaporização e respiração. O metabolismo exergético é calculado com base na variação da exergia de três reações de oxidação: carboidratos, lipídeos e aminoácidos. Para condições ambientais transientes, calcula-se a variação temporal da exergia do corpo, e ainda, o máximo trabalho que o corpo pode executar a partir da hidrólise do ATP (adenosina trifosfato). O corpo humano aproveita aproximadamente 60% da exergia dos macronutrientes ingeridos na forma de ATP, 5% é dissipada na forma de calor e o restante destruída. Se o indivíduo estiver em repouso, toda a exergia da molécula de ATP é destruída ou dissipada na forma de calor. A exergia destruída tende a diminuir em função da idade tanto para condição basal como também para atividades físicas. Calculou-se que a exergia destruída durante uma vida equivale a 3091MJ/kg (ou entropia gerada de 10,2MJ/kgK). O rendimento exergético, no entanto, diminui em decorrência da idade para condição basal, porém aumenta durante atividades físicas. Pode-se ainda afirmar que o corpo destrói menos exergia e é mais eficiente quando submetido a condições de alta temperatura operativa e baixa umidade relativa. A análise exergética acarretou em interpretações complementares ao balanço de energia, pois, a partir de sua aplicação, foi possível distinguir corredores de acordo com o nível de atividade física, ou seja, corredores mais bem treinados podem realizar mais trabalho para o mesmo valor de exergia destruída. Finalmente, foi possível identificar diferentes técnicas de hipotermia tomando por base a comparação das eficiências exergéticas.<br>Exergy analysis is applied to the human being aiming to assess the quality of the energy conversion processes that take place in the body, its several of systems and in biochemical reactions involved in these processes. It is known that life has a beginning, a development and an end, therefore, it is a typical example if irreversible process. As the chronological age and entropic generation are positive quantities (increases in the same direction), this last one is named arrow of time. Hence, it becomes possible to obtain indices based on the concept of destroyed exergy and exergy efficiency for different areas of knowledge such as: medicine (different techniques of hypothermia), sports (ergoespirometric test) and mechanical engineer (thermal comfort). To this end, it is proposed a model of the human body which takes into account the exergy transfer rates to the environment associated with radiation, convection, vaporization and respiration. The metabolism exergy basis is calculated based on the exergy variation of the reactions of oxidation of three reference substances: carbohydrates, lipids and amino acids. For transient environmental conditions it is calculated the exergy variation of the body over time. Moreover, it is possible to calculate the maximum work that can be obtained from the hydrolysis of ATP (adenosine triphosphate). This procedure was applied to a thermodynamic model of human body for basal conditions and to experimental results of runners during different level of physical activities. The human body uses about 60% of the exergy of nutrients to obtain ATP, the rest is destroyed or dissipated as heat. Destroyed exergy rate tends to decrease as a function of lifespan (for basal conditions and during physical activities). The destroyed exergy during lifespan was calculated as 3091MJ/kg (or entropy production of 10.2MJ/kgK). The exergy efficiency decreases as a function of age in basal condition, but it increases during physical activities. The destroyed exergy rate is smaller and the exergy efficiency is greater for high operative temperatures and low relative humidities. The exergy analysis led to additional information regarding the First Law of Thermodynamics, because from its application it was possible to differentiate runners according to their training level, for the same destroyed exergy better trained subjects could perform more work. Finally it was possible to distinguish different techniques of hypothermia from the concept of exergy efficiency.
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Gong, Mei, Göran Wall, and Sven Werner. "Energy and exergy analysis of district heating systems." Högskolan i Halmstad, Energiteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-20298.
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The concept of exergy is defined and applied to district heating systems. The influence from different reference state conditions and system boundaries are explained in some detail. The aim is to show the simplicity and value of using the concept of exergy when analyzing district heating processes. The exergy factor is introduced and applied for a number of Swedish and Danish district heating systems. This varies from 14.2% to 22.5% for Swedish district heating systems. The higher the exergy factor, the more the exergy losses in the passive conversion towards space heating. Large losses revealed in an exergy treatment of a process should be seen as a challenge to achieve technical improvements of the system.
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Voldsund, Mari. "Exergy analysis of offshore oil and gas processing." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for kjemi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-25310.
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Oil and gas extraction have been responsible for 25—28% of the total greenhouse gas emissions in Norway the last 10 years. The part from offshore oil and gas processing, including power production, flaring, and cold ventilation on production platforms, accounted for 20—22%. Exergy analysis is a method for systematic assessment of potential to perform work. It gives the possibility to identify where in a process inefficiencies occur: both losses to the surroundings and internal irreversibilities, and can be used as a tool for pinpointing improvement potential and for evaluation of industrial processes. When used in the petroleum sector, this can motivate more efficient oil and gas extraction, leading to a better utilisation of the resources and less greenhouse gas emissions. The objectives of this thesis were to: (i) establish exergy analyses of the oil and gas processing plants on different types of North Sea platforms; (ii) identify and discuss improvement potentials for each case, compare them and draw general conclusions if possible; and (iii) define meaningful thermodynamic performance parameters for evaluation of the platforms. Four real platforms (Platforms A—D) and one generic platform of the North Sea type were simulated with the process simulators Aspen HYSYS and Aspen Plus. The real platforms were simulated using process data provided by the oil companies. The generic platform was simulated based on literature data, with six different feed compositions (Cases 1—6). These five platforms presented different process conditions; they differed for instance by their exported products, gas-to-oil ratios, reservoir characteristics and recovery strategies. Exergy analyses were carried out, and it was shown that for the cases studied in this work, the power consumption was in the range of 5.5—30 MW, or 20—660 MJ/Sm3 o.e. exported. The heat demand was very small and covered by electric heating for two of the platforms, and higher, but low enough to be covered by waste heat recovery from the power turbines and by heat integration between process streams, for the other three platforms. The main part of the power was consumed by compressors in the gas treatment section for all cases, except Platform B and Case 4 of the generic model. Platform B had lower pressures in the products than in the feeds, resulting in a low compression demand. Case 4 of the generic model had a high content of heavy hydrocarbons in the feed, resulting in large power demand in the oil export pumping section. The recompression and oil pumping sections appeared to be the other major power consumers, together with the seawater injection system, if installed. The total exergy destruction was in the range of 12—32 MW, or 43—517 MJ/Sm3 o.e. exported. Most exergy destruction was related to pressure increase or decrease. Exergy destruction in the gas treatment section made up 8—57% of the total amount, destruction in the recompression section accounted for 11—29%, while 10—28% took place in the production manifolds. Exergy losses due to flaring varied in the range of 0—13 MW. Platforms with high gas-to-oil ratios and high pressures required in the gas product presented the highest power consumption and exergy destruction. Several measures were proposed for reduction of exergy destruction and losses. Two alternatives included use of mature technologies with potential to increase efficiency significantly: (i) limit flaring by installation of gas recovery systems, and (ii) improve gas compression performance by updating/exchanging the compressors. Several thermodynamic performance indicators were discussed, with Platforms A—D as case studies. None of the indicators could at the same time evaluate (i) utilisation of technical achievable potential, (ii) utilisation of theoretical achievable potential and (iii) total use of energy resources. It was concluded that a set of indicators had to be used to evaluate the thermodynamic performance. The following indicators were suggested: BAT efficiency on exergy basis, exergy efficiency, and specific exergy destruction. The formulation of exergy efficiency for offshore processing plants is difficult because of (i) the high throughput of chemical exergy, (ii) the large variety of chemical components in the process streams and (iii) the differences in operating conditions. Approaches found in the literature for similar processes were applied to Platforms A—D. These approaches had several drawbacks when applied to offshore processing plants; they showed low sensitivity to performance improvements, gave inconsistent results, or favoured platforms operating under certain conditions. A new exergy efficiency, called the component-by-component efficiency, was proposed. This efficiency could successfully evaluate the theoretical improvement potential. Eksergianalyse av offshore olje- og gassprosessering Olje- og gassutvinning har vært kilde til 25—28% av de totale klimagassutslippene i Norge de siste 10 årene. Den delen som stammer fra offshore olje- og gassprosessering (kraftproduksjon, fakling og kaldventilering på produksjonsplattformer) stod for 20—22%. Eksergianalyse er en metode for systematisk bestemmelse av potensiale til å utføre arbeid. Det gir mulighet til å identifisere hvor i en prosess ineffektiviteter oppstår: både i form av tap til omgivelsene og i form av interne irreversibiliteter. Det kan brukes som et verktøy for å finne forbedringsmuligheter og for evaluering av industrielle prosesser. Ved bruk innen petroleumssektoren kan dette motivere for mer effektiv olje- og gassutvinning, noe som gir bedre utnyttelse av ressursene og mindre utslipp av klimagasser. Formålet med denne avhandlingen er å: (i) etablere eksergianalyser av olje- og gassprosessering på ulike typer Nordsjø-plattformer; (ii) identifisere og diskutere forbedringspotensialer for hvert tilfelle, sammenligne dem og trekke generelle konklusjoner om mulig; og (iii) definere meningsfulle termodynamiske ytelsesindikatorer for evaluering av plattformene. Fire virkelige plattformer (Plattform A—D) og en generisk Nordsjø-type plattform er simulert med prosessimulatorene Aspen HYSYS og Aspen Plus. De virkelige plattformene er simulert ved å bruke prosessdata stilt til rådighet av operatørene av plattformene. Den generiske plattformen er simulert basert på litteraturdata, med seks ulike fødesammensetninger (Case 1—6). Disse fem plattformene har ulike prosessbetingelser; de har for eksempel ulike eksporterte produkter, gass/olje-forhold, reservoaregenskaper og utvinningsstrategier. Eksergianalyser viser at for tilfellene studert i dette arbeidet er kraftforbruket i størrelsesorden 5,5—30 MW, eller 20—660 MJ/Sm3 o.e. eksportert. Varmebehovet er svært lite og blir dekket med elektrisitet for to av plattformene, og noe høyere men lavt nok til å bli dekket med varmegjenvinning fra kraftturbinene og ved varmeveksling mellom prosesstrømmer for de tre andre plattformene. Hoveddelen av kraften blir konsumert av kompressorene i gassbehandlingsseksjonen for alle tilfellene bortsett fra Plattform B og Case 4 i den generiske modellen. Plattform B har lavere trykk i produktstrømmene enn i fødestrømmene, noe som resulterer i lavt behov for kompresjon. Case 4 i den generiske modellen har et høyt innhold av tunge hydrokarboner i føden, noe som resulterer i høyt kraftbehov i seksjonen for eksportpumping. Seksjonene for rekompresjon og eksportpumping viser seg å være de andre viktigste kraftforbrukerene, sammen med systemet for sjøvannsinjeksjon hvis dette er installert. Den totale ekserginedbrytingen er 12—32 MW, eller 43—517 MJ/Sm3 o.e. eksportert. Mest ekserginedbryting er relatert til trykkøking eller trykkreduksjon. Ekserginedbryting i gassbehandlingsdelen utgjør 8—57% av den totale mengden, nedbryting i rekompresjonsseksjonen utgjør 11-29%, mens nedbryting i produksjonsmanifoldene utgjør 10—28%. Eksergitap på grunn av fakling varierer mellom 0—13 MW. Plattformene med høye gass/olje-forhold og behov for høyt trykk i gassproduktene har høyest kraftforbruk og ekserginedbryting. Ulike tiltak for reduksjon av ekserginedbryting og eksergitap er foreslått. To alternativer inkluderer bruk av modne teknologier og har potensiale til å øke effektiviteten betydelig: (i) begrensning av fakling av gass ved installasjon av gassgjenvinningssystemer, og (ii) forbedring av gasskompresjonen ved å oppdatere/bytte ut kompressorer. Flere termodynamiske ytelsesindikatorer er diskutert med utgangspunkt i Plattform A—D. Ingen av indikatorene kan på samme tid evaluere (i) utnyttelse av teknisk oppnåelig potensiale, (ii) utnyttelse av teoretisk potensiale og (iii) total bruk av energiressurser. Det konkluderes med at et sett med indikatorer må brukes for å evaluere termodynamisk ytelse. De følgende indikatorene foreslås: BAT (best tilgjengelig teknologi) effektivitet på eksergibasis, eksergieffektivitet og spesifikk ekserginedbryting. Formuleringen av eksergieffektivitet for offshore olje- og gassprosessering er utfordrende på grunn av (i) den høye gjennomgangen av kjemisk eksergi, (ii) den store variasjonen av kjemiske komponenter i prosesstrømmene og (iii) de store forskjellene i driftsbetingelser. En ny type eksergieffektivitet foreslås. Denne effektiviteten kan evaluere utnyttelsen av det teoretiske potensialet på tross av punktene nevnt ovenfor.
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Quintanilla, Muñoz Alberto Martin. "Energy and exergy analysis of an HVAC system." Master's thesis, Pontificia Universidad Católica del Perú, 2017. http://tesis.pucp.edu.pe/repositorio/handle/123456789/9642.
Full textAbstract:
The efficient use of energy is a major issue nowadays. Environmental and economic purposes push
various investigations to focus on the performances of energy systems and equipment. In the context
of the coming energy transition, Heat, Ventilation and Air Conditioning (HVAC) systems will certainly
take an increasing and worldwide importance. In this work, energy and exergy analysis are used to
assess the performances of each component of an air treatment station. Results of energy and exergy
analysis for each process are presented. The most important result is that simple heating and cooling
processes with deshumidification have the worst exergy efficiencies; and that both processes represent
almost all the exergy losses of the studied HVAC system.<br>Tesis
Books on the topic "Exergy analysis"
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Cooper, A. C. G. Exergy analysis of several distillation column configurati. UMIST, 1987.
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Sussman, M. V. Availability (exergy) analysis: A self instruction manual. 3rd ed. Mulliken House, 1985.
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Szargut, Jan. Exergy analysis of thermal, chemical, and metallurgical processes. Hemisphere, 1988.
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F, Naterer Greg, ed. Energy and exergy analysis of hydrogen train propulsion. Knovel, 2011.
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Dinçer, İbrahim. Exergy: Energy, environment, and sustainable development. Elsevier, 2007.
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Brodyansky, V. M. The efficiency of industrial processes: Exergy analysis and optimization. Elsevier, 1994.
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Zheng, J. Combined pinch and exergy analysis for commercial power plant design. UMIST, 1996.
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Martinaitis, Vytautas, Giedrė Streckienė, and Juozas Bielskus. Exergy Analysis of the Air Handling Unit at Variable Reference Temperature. Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-97841-9.
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Kotas, T. J. Solutions manual to accompany the exergy method of thermal plant analysis. Krieger, 1995.
Find full textBook chapters on the topic "Exergy analysis"
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Tiwari, G. N., Arvind Tiwari, and Shyam. "Exergy Analysis." In Energy Systems in Electrical Engineering. Springer Singapore, 2016. http://dx.doi.org/10.1007/978-981-10-0807-8_19.
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Blok, Kornelis, and Evert Nieuwlaar. "Exergy analysis." In Introduction to Energy Analysis. Routledge, 2020. http://dx.doi.org/10.4324/9781003003571-7.
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de Oliveira, Silvio. "Chemical Processes Analysis and Improvement." In Exergy. Springer London, 2012. http://dx.doi.org/10.1007/978-1-4471-4165-5_5.
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de Oliveira Junior, Silvio. "Exergy Analysis and Environmental Impact." In Exergy. Springer London, 2012. http://dx.doi.org/10.1007/978-1-4471-4165-5_9.
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de Oliveira, Silvio. "Exergy Analysis and Human Body Behavior." In Exergy. Springer London, 2012. http://dx.doi.org/10.1007/978-1-4471-4165-5_10.
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de Oliveira, Silvio. "Exergy and Renewability Analysis of Liquid Biofuels Production Routes." In Exergy. Springer London, 2012. http://dx.doi.org/10.1007/978-1-4471-4165-5_7.
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de Oliveira, Silvio. "Exergy, Exergy Costing, and Renewability Analysis of Energy Conversion Processes." In Exergy. Springer London, 2012. http://dx.doi.org/10.1007/978-1-4471-4165-5_2.
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de Oliveira, Silvio. "Exergy and Thermoeconomic Analysis of Power Plants, Refrigeration and Polygeneration Systems." In Exergy. Springer London, 2012. http://dx.doi.org/10.1007/978-1-4471-4165-5_3.
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Huysman, Sofie, Thomas Schaubroeck, and Jo Dewulf. "Exergy and Cumulative Exergy Use Analysis." In Sustainability Assessment of Renewables-Based Products. John Wiley & Sons, Ltd, 2015. http://dx.doi.org/10.1002/9781118933916.ch10.
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Nikbakht, Ali M., Ahmad Piri, and Azharul Karim. "Exergy-Economic Analysis." In Applied Thermodynamics in Unit Operations. CRC Press, 2023. http://dx.doi.org/10.1201/9781003424680-8.
Full textConference papers on the topic "Exergy analysis"
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Silva, Valter, Abel Rouboa, Theodore E. Simos, George Psihoyios, Ch Tsitouras, and Zacharias Anastassi. "Methane Combustion: An Exergy Analysis." In NUMERICAL ANALYSIS AND APPLIED MATHEMATICS ICNAAM 2011: International Conference on Numerical Analysis and Applied Mathematics. AIP, 2011. http://dx.doi.org/10.1063/1.3637751.
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Fagbenle, Richard Olayiwola, Sunday Sam Adefila, Sunday Oyedepo, and Moradeyo Odunfa. "Exergy, Exergoeconomic and Exergoenvironomic Analyses of Selected Gas Turbine Power Plants in Nigeria." In ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-40311.
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Energy supply trends as well as environmental regulations and climate change issues have made it necessary to closely scrutinize the way energy is utilized. Efficient energy utilization thus requires paying more attention to accurate and advanced thermodynamic analysis of thermal systems. Hence, methods aimed at evaluating the performances of energy systems take into account the Energy, Environment and Economics. Therefore, the first and second law of thermodynamics combined with economics and environmental impact represents a very powerful tool for the systematic study and optimization of energy systems. In this study, a thermodynamic analysis of eleven selected gas turbine power plants in Nigeria was carried out using the first and second laws of thermodynamics, economic and environmental impact concepts. Exergetic, exergo-economic and exergo-environmental analyses were conducted using operating data obtained from the power plants to determine the exergy destruction and exergy efficiency of each major component of the gas turbine in each power plant. The exergy analysis confirmed that the combustion chamber is the most exergy destructive component compared to other cycle components as expected. The percentage exergy destruction in combustion chamber varied between 86.05 and 94.6%. Increasing the gas turbine inlet temperature (GTIT), the exergy destruction of this component can be reduced. Exergo-economic analysis showed that the cost of exergy destruction is high in the combustion chamber and by increasing the GTIT effectively decreases this cost. The exergy costing analysis revealed that the unit cost of electricity produced in the plants ranged from cents 1.88/kWh (₦2.99/kWh) to cents 5.65/kWh (₦8.98/kWh). Exergo-environmental analysis showed that the CO2 emissions varied between 100.18 to 408.78 kgCO2/MWh while cost rate of environmental impact varied from 40.18 $/h (N6, 388.62/h) to 276.97 $/h (N44, 038.23/h). The results further showed that CO2 emissions and cost of environmental impact decrease with increasing GTIT.
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Qin, Qin, Xiuli Zhang, Shenkuai Lv, Qingbo Yu, and Dongyu Lang. "Exergy Analysis of Ironmaking System." In 2012 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC). IEEE, 2012. http://dx.doi.org/10.1109/appeec.2012.6307497.
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Wang, BoNian, and GuoHe Yu. "STUDY ON THE EXERGY ANALYSIS." In Energy and Environment, 1995. Begellhouse, 2023. http://dx.doi.org/10.1615/1-56700-052-5.290.
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Gilbert, Andrew, Bryan Mesmer, and Michael D. Watson. "Exergy analysis of rocket systems." In 2015 9th Annual IEEE International Systems Conference (SysCon). IEEE, 2015. http://dx.doi.org/10.1109/syscon.2015.7116765.
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Mosquim, Rafael, Carlos Eduardo Keutenedjian Mady, and Silvio de Oliveira Junior. "SÃO PAULO STATE EXERGY ANALYSIS." In 16th Brazilian Congress of Thermal Sciences and Engineering. ABCM, 2016. http://dx.doi.org/10.26678/abcm.encit2016.cit2016-0013.
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O¨zdemir, Mehmed Rafet, Ali Kos¸ar, Orc¸un Demir, Cemre O¨zenel, and Og˘uzhan Bahc¸ivan. "Thermal Hydraulic, Exergy and Exergy-Economic Analysis of Micro Heat Sinks at High Flow Rates." In ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis. ASMEDC, 2010. http://dx.doi.org/10.1115/esda2010-25239.
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Recently, micro/nanofabrication technology has been used to develop a number of microfluidic systems. With its integration to microfluidic devices, microchannels and micro scale pin fin heat sinks find applications in many areas such as drug delivery and propulsion in biochemical reaction chambers and micro mixing. Many research efforts have been performed to reveal thermal and hydrodynamic performances of microchannel based micro fluidic devices. In the current study, it is aimed to extend the knowledge on this field by investigating heat and fluid flow in micro heat sinks at high flow rates. Moreover, thermodynamic and thermo-economic aspects were also considered. De-ionized water was used as the coolant in the system. Flow rates were measured over pressures of 20–80 psi. A serpentine heater was deposited at the back of the micro pin fin devices to enable the delivery of heat to these devices. Two micro-pin fin devices each having different geometrical properties (Circular based and Hydrofoil based) were used in this study. In addition, the performances (thermal-hydraulic, exergy, exergo-economic) were also experimentally obtained for a plain microchannel device. Thermal resistances, exergy efficiencies and thermo-economic parameters were obtained from the devices and their performances were assessed.
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Lourenço, Atilio B., José Joaquim C. S. Santos, and João Luiz M. Donatelli. "Exergy Analysis and Fuel Exergy Allocation in a HTGR Direct Combined Cycle." In 2012 20th International Conference on Nuclear Engineering and the ASME 2012 Power Conference. ASME, 2012. http://dx.doi.org/10.1115/icone20-power2012-54523.
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Wang, Aijun, Xiaotao Zhang, and Minghua Huang. "Exergy analysis of biomass gasification process." In 2013 International Conference on Materials for Renewable Energy and Environment (ICMREE). IEEE, 2013. http://dx.doi.org/10.1109/icmree.2013.6893650.
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Ri-yi, Lin, Yu Xichong, Li Jian, Li Yuxing, and Wang Wuchang. "Exergy Analysis for LNG Refrigeration Cycle." In 2011 International Conference on Computer Distributed Control and Intelligent Environmental Monitoring (CDCIEM). IEEE, 2011. http://dx.doi.org/10.1109/cdciem.2011.461.
Full textReports on the topic "Exergy analysis"
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Gorla, Rama S. Exergy Analysis for Energy Systems. Defense Technical Information Center, 2006. http://dx.doi.org/10.21236/ada473052.
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Rabiti, Cristian, Robert S. Cherry, Wesley R. Deason, Piyush Sabharwall, Shannon M. Bragg-Sitton, and Richard D. Boardman. Framework for the Economic Analysis of Hybrid Systems Based on Exergy Consumption. Office of Scientific and Technical Information (OSTI), 2014. http://dx.doi.org/10.2172/1169251.
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Gravina, Antonio Francesco, and Matteo Lanzafame. Demography, Growth, and Robots in Advanced and Emerging Economies. Asian Development Bank, 2023. http://dx.doi.org/10.22617/wps230478-2.
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This paper estimates the impact of demographic change on labor productivity growth. The analysis covers a panel of 90 advanced and emerging economies over 1961-2018 and produces three main findings. First, increases in the young and old population shares exert significantly negative effects on labor productivity growth, working via various channels. Second, population aging has a greater negative impact on emerging economies than on advanced economies. Third, automation reduces the negative effects of unfavorable demographic change—in particular, population aging.
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Kankash, Н., Т. Cherkasova, S. Novoseletska, N. Shapran, and L. Bilokonenko. The Use of Linguistic Means of Figurativeness and Evaluativity to Exert Influence in the Speeches of the Chief Delegates of the Ukrainian SSR at the Sessions of the UN General Assembly. Криворізький державний педагогічний університет, 2020. http://dx.doi.org/10.31812/123456789/4648.
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The purpose of the study is to identify the figurative means in the formal diplomatic texts of speeches of chief delegates of the Ukrainian SSR to exert influence at the sessions of the UN General Assembly. Based on the interpretive method of speech analysis and the method of generalisation of the data obtained, an attempt was made to identify the main figurative means and expressiveness of speech, which help to achieve the effect of influence on the reader (listener). In order to identify hidden meanings, a hermeneutic approach to understanding texts was used. According to the results of the study, the most actively used linguistic means of figurativeness in the considered texts are epithets, metaphors, phraseologies. There are many more negative epithets used in the texts of speeches than positive ones, which aim to make people aware of the idea of self-preservation, to arouse emotions of anxiety, fear, vigilance. Metaphors of positive and negative evaluation are used to verbalise mental states, social states and thought processes. Most of the epithets, metaphors, idioms represented in the text are used to denote a negative evaluation, which is perceived as a deviation from the norm and is motivated by the following factors: the reluctance of people to take positive action, irresponsible attitude of some people towards others, socially unacceptable flaws and shortcomings. A logical continuation of this study is the analysis of linguistic means of figurativeness and evaluativity of other types of texts of the official style, including statements and conventions.
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Kamaruzzaman, Mohd Amir, Muhammad Hibatullah Romli, Razif Abas, et al. Impact of Endocannabinoid Mediated Glial Cells on Cognitive Function in Alzheimer’s Disease: A Systematic Review and Meta-Analysis of Animal Studies. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, 2022. http://dx.doi.org/10.37766/inplasy2022.8.0094.
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Review question / Objective: This review aims to review systematically, and meta-analyse published pre-clinical research about the mechanism of endocannabinoid system modulation on glial cells and their effects on cognitive function in designated Alzheimer’s Disease (AD) in the animal model. Condition being studied: Its been acknowledged that the cure of Alzheimer's disease is still vague. Current medicine is working on symptoms only but never stop the disease progression due to neuronal loss. In recent years, researches have found that cannabinoid which is derived from cannabis sativa plant and its compounds exert neuroprotective effects in vitro and in vivo. In fact, cognitive improvement has been shown in some clinical studies. Therefore, the knowledge of cannabinoids and its interaction with living physiological environment like glial cells is crucial as immunomodulation to strategize the potential target of this substance. The original articles from related study relating endocannabinoid mediated glial cell were extracted to summarize and meta-analyze its impact and possible mechanism against cognitive decline in AD.
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Fontanari, Claudia, and Antonella Palumbo. Permanent Scars: The Effects of Wages on Productivity. Institute for New Economic Thinking Working Paper Series, 2022. http://dx.doi.org/10.36687/inetwp187.
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This paper explores how stagnating real wages may have contributed to the slowdown of US productivity. Through shift-share analysis, we find that after a sharp change in distribution against wages, some historically high-productivity sectors (like manufacturing) switched towards slower productivity growth. This supports our hypothesis that the anemic growth of productivity may be partly due to the trend toward massive use of cheap labor. Our estimation of Sylos Labini’s productivity equation confirms the existence of two direct effects of wages, one acting through the incentive to mechanization and the other through the incentive to reorganize labor use. We also show that labor ‘weakness’ may exert a further negative effect on labor productivity. On the whole, we find that a persistent regime of low wages may determine very negative long-term consequences on the economy.
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Lui, Rui, Cheng Zhu, John Schmalzel, et al. Experimental and numerical analyses of soil electrical resistivity under subfreezing conditions. Engineer Research and Development Center (U.S.), 2024. http://dx.doi.org/10.21079/11681/48430.
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The engineering behavior of frozen soils is critical to the serviceability of civil infrastructure in cold regions. Among various geophysical techniques, electrical resistivity imaging is a promising technique that is cost effective and provides spatially continuous subsurface information. In this study, under freeze–thaw conditions, we carry out lab–scale 1D electrical resistivity measurements on frost–susceptible soils with varying water content and bulk density properties. We use a portable electrical resistivity meter for temporal electrical resistivity measurements and thermocouples for temperature monitoring. Dynamic temperature-dependent soil properties, most notably unfrozen water content, exert significant influences on the observed electrical resistivity. Below 0 °C, soil resistivity increases with the decreasing temperature. We also observe a hysteresis effect on the evolution of electrical resistivity during the freeze–thaw cycle, which effect we characterize with a sigmoidal model. At the same temperature, electrical resistivity during freezing is consistently lower than that during thawing. We have implemented this sigmoidal model into a COMSOL finite element model at both laboratory and field scales which enables the simulation of soil electrical resistivity response under both short–term and long–term sub–freezing conditions. Atmospheric temperature variations induce soil temperature change, and thereby phase transition and electrical resistivity change, with the rate of change being a function of the depth of investigation and soil properties include initial water content and initial temperature. This study advances the fundamental understanding of the electrical behaviors of frozen soils and enhance the application of electrical geophysical investigations in cold regions.
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Singh, Anjali. Estimating the Chiasma Frequency in Diplotene-Diakinesis Stage. ConductScience, 2020. http://dx.doi.org/10.55157/cs20200925.
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Chiasma is the point of crossing over or site where the exchange of genetic material takes place between two homologous, non-sister chromatids. The crossover occurs in the pachytene stage, however, it is observed in the diplotene stage of meiosis-I[2]. The cross-over between the two homologs also creates a new combination of parental genes, forming recombinants. The recombination of the genes causes variation in the population and exert a profound effect on genomic diversity and evolution. Meiotic recombination and variation in the population have been a concern for scientists to understand the impact and significance of crossing over in a population. Over time, various techniques, such as immunolocalization and electron microscopy of recombination nodules[2], were discovered for the analysis of meiotic recombination and quantification of crossing over. However, estimation of chiasma frequency is the traditional method followed widely to understand the phenomenon. Chiasma Frequency is defined as the estimation of the level of genetic recombination in a population. It is especially very effective to estimate the genetic recombination in organisms in which genetic analysis is impossible/difficult to perform[2]. So, this article is a layout of the origin of the concept of chiasmata, the factors affecting chiasma frequency, and its distribution in chromosomes. Also discussed, is the procedure for estimating chiasma frequency in plants as well as animals.
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Gentelet, Karine, and Alexandra Bahary-Dionne. Les angles morts des réponses technologiques à la pandémie de COVID-19 : Disjonction entre les inégalités en santé et numériques structurantes de la marginalisation de certaines populations. Observatoire international sur les impacts sociétaux de l’intelligence artificielle et du numérique, 2020. http://dx.doi.org/10.61737/gsjs3130.
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Dans le cadre des travaux de OBVIA sur les effets des systèmes d’intelligence artificielle et des outils numériques déployés pour lutter contre la propagation de la COVID-19, Karine Gentelet, professeure agrégée au Département des sciences sociales de l’Université du Québec en Outaouais (UQO) et titulaire de la Chaire Abéona-ENS-OBVIA en intelligence artificielle et justice sociale et Alexandra Bahary-Dionne, candidate au doctorat en droit à l’Université d’Ottawa, ont produit un rapport de recherche intitulé: « Les angles morts des réponses technologiques à la pandémie de COVID-19 : Disjonction entre les inégalités en santé et numériques structurantes de la marginalisation de certaines populations« . Ce rapport propose une analyse des réponses technologiques à la pandémie en particulier, lorsqu’appliquées à des populations qui sont déjà marginalisées. Ce rapport met en exergue un certain nombre d’angles morts qui ont eu pour conséquence de ne pas considérer les liens étroits entre les inégalités en santé déjà existantes et le caractère multidimensionnel des fractures numériques.
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Jorge, Guillermo. Identification and Exchange of Information on Politically Exposed Persons in Central American Countries. Inter-American Development Bank, 2018. http://dx.doi.org/10.18235/0010714.
Full textAbstract:
In the fight against money laundering, information on politically exposed persons (PEPs) is highly relevant for financial institutions as it is about customers deemed to be high-risk due to their public functions and the degree of influence they can exert. This document reviews the regulatory and operational frameworks to access and exchange of information on PEPs in Central American countries, as well as the enhanced due diligence measures under implementation in these countries. The main findings indicate that there are legal constraints in relation to the definition of PEPs and the obligation to declare beneficial owners. There are also operational constraints in terms of the measures implemented to identify PEPs and to ensure the integrity of information systems. Likewise, this document presents recommendations to address the barriers identified and analyzes best practices to help strengthen the detection and prevention mechanisms used by Central American governments and financial institutions for cases in which PEPs use the financial system to launder money obtained through corruption and related crimes.