Articles de revues : « THERMODYNAMICS PERFORMANCE »

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Mitrovic, Dejan, Marko Ignjatovic, Branislav Stojanovic, Jelena Janevski et Mirko Stojiljkovic. « Comparative exergetic performance analysis for certain thermal power plants in Serbia ». Thermal Science 20, suppl. 5 (2016) : 1259–69. http://dx.doi.org/10.2298/tsci16s5259m.

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Traditional methods of analysis and calculation of complex thermal systems are based on the first law of thermodynamics. These methods use energy balance for a system. In general, energy balances do not provide any information about internal losses. In contrast, the second law of thermodynamics introduces the concept of exergy, which is useful in the analysis of thermal systems. Exergy is a measure for assessing the quality of energy, and allows one to determine the location, cause, and real size of losses incurred as well as residues in a thermal process. The purpose of this study is to comparatively analyze the performance of four thermal power plants from the energetic and exergetic viewpoint. Thermodynamic models of the plants are developed based on the first and second law of thermodynamics. The primary objectives of this paper are to analyze the system components separately and to identify and quantify the sites having largest energy and exergy losses. Finally, by means of these analyses, the main sources of thermodynamic inefficiencies as well as a reasonable comparison of each plant to others are identified and discussed. As a result, the outcomes of this study can provide a basis for the improvement of plant performance for the considered thermal power plants.

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Ng, K. C., T. Y. Bong et H. T. Chua. « Performance Evaluation of Centrifugal Chillers in an Air-Conditioning Plant with The Building Automation System (BAS) ». Proceedings of the Institution of Mechanical Engineers, Part A : Journal of Power and Energy 208, n^o 4 (novembre 1994) : 249–55. http://dx.doi.org/10.1243/pime_proc_1994_208_045_02.

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A thermodynamic model with a novel method of describing the performances of centrifugal chillers for air-conditioning is presented. It is based on the first and second laws of thermodynamics which captures the overall entropy change due to non-isentropic compression and expansion of the thermodynamic cycle. The model gives the fundamental relation between the coefficient of performance (COP) and the cooling rates (Qe) for (a) the modulating and (b) the throttling actions of the inlet guide-vanes of the compressor. The usefulness and the accuracy of the model are demonstrated here by analysing the in situ performance of two commercial, installed centrifugal chillers of an air-conditioning plant as well as comparing the available performance data of another chiller in the literature.

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Bejan, Adrian, et George Tsatsaronis. « Purpose in Thermodynamics ». Energies 14, n^o 2 (13 janvier 2021) : 408. http://dx.doi.org/10.3390/en14020408.

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This is a review of the concepts of purpose, direction, and objective in the discipline of thermodynamics, which is a pillar of physics, natural sciences, life science, and engineering science. Reviewed is the relentless evolution of this discipline toward accounting for evolutionary design with direction, and for establishing the concept of purpose in methodologies of modeling, analysis, teaching, and design optimization. Evolution is change after change toward flow access, with direction in time, and purpose. Evolution does not have an ‘end’. In thermodynamics, purpose is already the defining feature of methods that have emerged to guide and facilitate the generation, distribution, and use of motive power, heating, and cooling: thermodynamic optimization, exergy-based methods (i.e., exergetic, exergoeconomic, and exergoenvironmental analysis), entropy generation minimization, extended exergy, environomics, thermoecology, finite time thermodynamics, pinch analysis, animal design, geophysical flow design, and constructal law. What distinguishes these approaches are the purpose and the performance evaluation used in each method.

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He, Rong, Xinli Wei et Nasruddin Hassan. « Multi-objective performance optimization of ORC cycle based on improved ant colony algorithm ». Open Physics 17, n^o 1 (28 mars 2019) : 48–59. http://dx.doi.org/10.1515/phys-2019-0006.

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Abstract To solve the problem of multi-objective performance optimization based on ant colony algorithm, a multi-objective performance optimization method of ORC cycle based on an improved ant colony algorithm is proposed. Through the analysis of the ORC cycle system, the thermodynamic model of the ORC system is constructed. Based on the first law of thermodynamics and the second law of thermodynamics, the ORC system evaluation model is established in a MATLAB environment. The sensitivity analysis of the system is carried out by using the system performance evaluation index, and the optimal working parameter combination is obtained. The ant colony algorithm is used to optimize the performance of the ORC system and obtain the optimal solution. Experimental results show that the proposed multi-objective performance optimization method based on the ant colony algorithm for the ORC cycle needs a shorter optimization time and has a higher optimization efficiency.

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HE, JI-ZHOU, XIAN HE et JIE ZHENG. « THERMAL ENTANGLED QUANTUM REFRIGERATOR WORKING WITH THE TWO-QUBIT HEISENBERG XX MODEL ». International Journal of Modern Physics B 26, n^o 11 (30 avril 2012) : 1250086. http://dx.doi.org/10.1142/s0217979212500865.

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An entangled quantum refrigerator working with a two-qubit Heisenberg XX model in a constant external magnetic field is constructed in this paper. Based on the quantum first law of thermodynamics, the expressions for several basic thermodynamic quantities such as the heat transferred, the net work and the coefficient of performance are derived. Moreover, the influence of the thermal entanglement on the basic thermodynamic quantities is investigated. Several interesting features of the variation of the basic thermodynamic quantities with the thermal entanglement in zero and nonzero magnetic field are obtained. Lastly, we analyze the maximum coefficient of performance.

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Vischi, Francesco, Matteo Carrega, Alessandro Braggio, Pauli Virtanen et Francesco Giazotto. « Thermodynamics of a Phase-Driven Proximity Josephson Junction ». Entropy 21, n^o 10 (15 octobre 2019) : 1005. http://dx.doi.org/10.3390/e21101005.

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We study the thermodynamic properties of a superconductor/normal metal/superconductor Josephson junction in the short limit. Owing to the proximity effect, such a junction constitutes a thermodynamic system where phase difference, supercurrent, temperature and entropy are thermodynamical variables connected by equations of state. These allow conceiving quasi-static processes that we characterize in terms of heat and work exchanged. Finally, we combine such processes to construct a Josephson-based Otto and Stirling cycles. We study the related performance in both engine and refrigerator operating mode.

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Alghamdi, Mohammed, Ibrahim Al-Kharsan, Sana Shahab, Abdullah Albaker, Reza Alayi, Laveet Kumar et Mamdouh El Haj Assad. « Investigation of Energy and Exergy of Geothermal Organic Rankine Cycle ». Energies 16, n^o 5 (25 février 2023) : 2222. http://dx.doi.org/10.3390/en16052222.

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In this study, modeling and thermodynamic analysis of the combined double flash geothermal cycle generation was conducted using zeotropic fluid as the working fluid in the Organic Rankine Cycle (ORC). The analysis was performed based on the first and second laws of thermodynamics. Hexane, cyclohexane, isohexane, R245fa, and R236ea exhibit good performance at higher temperatures. In this study, three fluids—hexane, cyclohexane, and isohexane—were used. First, the model results for the pure fluids were compared with those of previous studies. Then, the important parameters of the cycle, including the efficiency of the first law of thermodynamics, the efficiency of the second law of thermodynamics, net productive power, and the amount of exergy destruction caused by changing the mass fraction of the refrigerant for the zeotropic fluids (investigated for the whole cycle and ORC), were obtained and compared.

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Chen, Pengfan, Ying Wang, Wenhao Ding, Yafeng Niu, Zibo Lin et Yingwen Liu. « Performance analysis of free piston Stirling engine based on the phasor notation method ». E3S Web of Conferences 313 (2021) : 02004. http://dx.doi.org/10.1051/e3sconf/202131302004.

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The free piston Stirling engine (FPSE) is a couple system of dynamics and thermodynamics. Due to the complicated and interactive relationships between the dynamic parameters and thermodynamic parameters, the performance of the FPSE is always difficult to predict and evaluate. The phasor notation method is proposed based on a thermodynamic-dynamic coupled model of a beta-type FPSE in this paper. The output power and efficiency under the different heating temperature and charging pressure are analysed and compared. In addition, based on the Sage numerical model, the influences of heating temperature and charging pressure on the pistons’ displacement amplitudes, power work and efficiency are revealed. This study can provide the assistance for the performance analysis, prediction and optimization of the FPSE.

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Fu, Jiawei, Zhenhua Liu, Xingyang Yang, Sumin Jin et Jilei Ye. « Limiting Performance of the Ejector Refrigeration Cycle with Pure Working Fluids ». Entropy 25, n^o 2 (24 janvier 2023) : 223. http://dx.doi.org/10.3390/e25020223.

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An ejector refrigeration system is a promising heat-driven refrigeration technology for energy consumption. The ideal cycle of an ejector refrigeration cycle (ERC) is a compound cycle with an inverse Carnot cycle driven by a Carnot cycle. The coefficient of performance (COP) of this ideal cycle represents the theoretical upper bound of ERC, and it does not contain any information about the properties of working fluids, which is a key cause of the large energy efficiency gap between the actual cycle and the ideal cycle. In this paper, the limiting COP and thermodynamics perfection of subcritical ERC is derived to evaluate the ERC efficiency limit under the constraint of pure working fluids. 15 pure fluids are employed to demonstrate the effects of working fluids on limiting COP and limiting thermodynamics perfection. The limiting COP is expressed as the function of the working fluid thermophysical parameters and the operating temperatures. The thermophysical parameters are the specific entropy increase in the generating process and the slope of the saturated liquid, and the limiting COP increases with these two parameters. The result shows R152a, R141b, and R123 have the best performance, and the limiting thermodynamic perfections at the referenced state are 86.8%, 84.90%, and 83.67%, respectively.

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Asnaghi, A., S. M. Ladjevardi, P. Saleh Izadkhast et A. H. Kashani. « Thermodynamics Performance Analysis of Solar Stirling Engines ». ISRN Renewable Energy 2012 (5 juillet 2012) : 1–14. http://dx.doi.org/10.5402/2012/321923.

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This paper provides numerical simulation and thermodynamic analysis of SOLO 161 Solar Stirling engine. Some imperfect working conditions, pistons' dead volumes, and work losses are considered in the simulation process. Considering an imperfect regeneration, an isothermal model is developed to calculate heat transfer. Hot and cold pistons dead volumes are accounted in the work diagram calculations. Regenerator effectiveness, heater and cooler temperatures, working gas, phase difference, average engine pressure, and dead volumes are considered as effective parameters. By variations in the effective parameters, Stirling engine performance is estimated. Results of this study indicate that the increase in the heater and cooler temperature difference and the decrease in the dead volumes will lead to an increase in thermal efficiency. Moreover, net work has its maximum value when the angle between two pistons shaft equal to 90 degrees while efficiency is maximum in 110 degrees.

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Zheng, Guozhong, et Youyin Jing. « Thermodynamics Performance Study on Water Source Heat Pump in Variant Operating Condition ». Energy & ; Environment 20, n^o 4 (août 2009) : 517–32. http://dx.doi.org/10.1260/095830509788707284.

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Water source heat pumps have outstanding advantages: significant energy conservation, working stability and notable pollution reduction. In this paper, the benefits and features of the water source heat pump are described. Then the methodology for studying the thermodynamics performance in variant conditions is described and the thermodynamics analysis of a specific water source heat pump is presented based on the first law of thermodynamics and exergy analysis theory to study the thermodynamics performance in variant condition. Coefficient of Performance (COP) and exergy efficiency in variant operating condition are calculated. The relation of COP and exergy efficiency with the outlet temperature of the chilled water and the inlet temperature of the cooling water are respectively studied. The operating strategies of both summer and winter condition are then concluded. Finally, the thermodynamics performance of the water source heat pump is compared with the other common refrigerating and heating equipments. It is concluded that the water source heat pump has great advantage over others in terms of energy saving. It is expected that the study would be beneficial to the researchers and engineers.

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Chimal-Eguia, J., R. Paez-Hernandez, Delfino Ladino-Luna et Juan Velázquez-Arcos. « Performance of a simple energetic-converting reaction model using Linear Irreversible Thermodynamics ». Entropy 21, n^o 11 (24 octobre 2019) : 1030. http://dx.doi.org/10.3390/e21111030.

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In this paper, the methodology of the so-called Linear Irreversible Thermodynamics (LIT) is applied to analyze the properties of an energetic-converting biological process using simple model for an enzymatic reaction that couples one exothermic and one endothermic reaction in the same fashion as Diaz-Hernandez et al. (Physica A, 2010, 389, 3476–3483). We extend the former analysis to consider three different operating regimes; namely, Maximum Power Output (MPO), Maximum Ecological Function (MEF) and Maximum Efficient Power Function (MEPF), respectively. Based on the later, it is possible to generalize the obtained results. Additionally, results show analogies in the optimal performance between the different optimization criteria where all thermodynamic features are determined by three parameters (the chemical potential gap Δ = μ 1 − μ 4 R T , the degree of coupling q and the efficiency η ). This depends on the election that leads to more or less efficient energy exchange.

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Yang, Li Yan, Yi Hui Guo et Li Li Yu. « Preparation and Thermodynamics Adsorption Performance of Cobalt Ions on the Crosslinked Starch Microspheres ». Advanced Materials Research 726-731 (août 2013) : 435–39. http://dx.doi.org/10.4028/www.scientific.net/amr.726-731.435.

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A type of cross-linking starch microspheres (CSMs) has been synthesized by reversed phase suspension method using soluble starch as raw material. Crosslinked starch microsphere has good adsorption performance to metal ions in water. The static adsorption behaviors of Co2+on the cross-linked starch microspheresand were investigated. The CSMs and its adsorption product were comparatively characterized by Fourier Transform Infrared Spectroscopy (FTIR). The adsorption behaviour of CSMs in different temperatures is in agreement with the Freundlich isothermal equation and isothermal equation of Langmiur. The thermodynamic parameters of adsorption process indicate that entropy is the main adsorption driving force, and physical adsorption is main about the adsorption behaviors of CSMs on Co2+.These data are helpful for the adsorption separation of metal ions and the treatment of the wastewater containing Co2+. Keywords: cross-linked starch microspheres;cobalt ions;adsorption mechanism;thermodynamics adsorption

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Zou, Chen-Juan, Yue Li, Jia-Kun Xu, Jia-Bin You, Ching Eng Png et Wan-Li Yang. « Geometrical Bounds on Irreversibility in Squeezed Thermal Bath ». Entropy 25, n^o 1 (9 janvier 2023) : 128. http://dx.doi.org/10.3390/e25010128.

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Irreversible entropy production (IEP) plays an important role in quantum thermodynamic processes. Here, we investigate the geometrical bounds of IEP in nonequilibrium thermodynamics by exemplifying a system coupled to a squeezed thermal bath subject to dissipation and dephasing, respectively. We find that the geometrical bounds of the IEP always shift in a contrary way under dissipation and dephasing, where the lower and upper bounds turning to be tighter occur in the situation of dephasing and dissipation, respectively. However, either under dissipation or under dephasing, we may reduce both the critical time of the IEP itself and the critical time of the bounds for reaching an equilibrium by harvesting the benefits of squeezing effects in which the values of the IEP, quantifying the degree of thermodynamic irreversibility, also become smaller. Therefore, due to the nonequilibrium nature of the squeezed thermal bath, the system–bath interaction energy has a prominent impact on the IEP, leading to tightness of its bounds. Our results are not contradictory with the second law of thermodynamics by involving squeezing of the bath as an available resource, which can improve the performance of quantum thermodynamic devices.

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Liu, Shuai, Fangjun Liu, Zhanhao Yan, Baohua Nie, Touwen Fan, Dongchu Chen et Yu Song. « Nucleation of L12-Al3M (M = Sc, Er, Y, Zr) Nanophases in Aluminum Alloys : A First-Principles ThermodynamicsStudy ». Crystals 13, n^o 8 (9 août 2023) : 1228. http://dx.doi.org/10.3390/cryst13081228.

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High-performance Sc-containing aluminum alloys are limited in their industrial application due to the high cost of Sc elements. Er, Zr, and Y elements are candidates for replacing Sc elements. Combined with the first-principles thermodynamic calculation and the classical nucleation theory, the nucleation of L12-Al3M (M = Sc, Er, Y, Zr) nanophases in dilutealuminum alloys were investigated to reveal their structural stability. The calculated results showed that the critical radius and nucleation energy of the L12-Al3M phases were as follows: Al3Er > Al3Y > Al3Sc > Al3Zr. The Al3Zr phase was the easiest to nucleate in thermodynamics, while the nucleation of the Al3Y and Al3Er phases were relatively difficult in thermodynamics. Various structures of Al3(Y, Zr) phases with the radius r < 1 nm can coexist in Al-Y-Zr alloys. At a precipitate’s radius of 1–10 nanometers, the core–shelled Al3Zr(Y) phase illustrated the highest nucleation energy, while the separated structure Al3Zr/Al3Y obtained the lowest one, and had thermodynamic advantages in the nucleation process. Moreover, the core–shelled Al3Zr(Y) phase obtained a higher nucleation energy than Al3Zr(Sc) and Al3Zr(Er). Core–doubleshelled Al3Zr/Er(Y) obtained a lower nucleation energy than that of Al3Zr(Y) due to the negative ΔGchem of Al3Er and the negative Al3Er/Al3Y interfacial energy, and was preferentially precipitated in thermodynamics stability.

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Patil, Sharad D., et Kanhaiya P. Powar. « Adoption of Experiential Learning Approach for Validation of Perpetual Motion Machine of First Kind Concept in Engineering Thermodynamics ». Journal of Engineering Education Transformations 36, S2 (1 janvier 2023) : 385–90. http://dx.doi.org/10.16920/jeet/2023/v36is2/23058.

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Educationalists among the globe are innovating and experimenting innovative teaching practices to the students to trigger students involvement, grasp of the concepts and performance. Engaging students in practical and challenging activities is one of the way to engage students in the learning process. The learning through inference drawn from these activities and experience is referred as an experiential learning. Experiential learning has evolved as a superior teaching-learning methodology over conventional classroom teaching. Autonomy in learning to the students and triggering creative thinking in students are the key aspects of experiential learning methodology. Educationalists have adopted experiential learning to science and technology, medical, management and engineering disciplines and is being more popular day by day. This article presents experiential learning model applied to engineering thermodynamics course (subject) for validation of basic thermodynamic concepts. Student validated working of a machine without any work input by reproducing the machine claimed in the videos uploaded on video sharing platforms. Flexible learning system helped students to have proper understanding of basic concepts, laws of thermodynamics and understanding and to improve academic performance. The activity conducted resulted in the improvement in the overall CO attainment by 14.12% along with improvement in the average marks of the students for UT1, UT2 and ESE assessment collectively by more than 55%. Keywords— Experiential learning; learning by doing; engineering thermodynamics; flexible learning framework.

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Bejan, Adrian. « Thermodynamics of heating ». Proceedings of the Royal Society A : Mathematical, Physical and Engineering Sciences 475, n^o 2223 (mars 2019) : 20180820. http://dx.doi.org/10.1098/rspa.2018.0820.

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Heat transfer is a mature science, and so is thermodynamics. They are almost 200 years old having developed largely independently until the 1980s. Maturity comes from the usefulness and success of the thermal sciences. This review uses the thermodynamics of heat transfer to focus on aspects that are usually not discussed in physics: performance, purpose, function, objective and direction of evolutionary design. The article illustrates the unity of the thermal sciences discipline (heat transfer +thermodynamics + constructal law), and uses the opportunity to correct a few recent interpretations of the thermodynamics of heat transfer regarding dissipative engines and energy storage.

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Dong, Hai Hong, Lin Ruan, Shu Qin Guo, Rui Cao et Jin Xiu Chen. « Study of the Thermodynamic Processes and Performance Evaluation of Self-Circulation Evaporative Cooling System in Hydro-Generator ». Applied Mechanics and Materials 488-489 (janvier 2014) : 979–82. http://dx.doi.org/10.4028/www.scientific.net/amm.488-489.979.

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The self-circulation evaporative cooling system (SECS) of stator collector ring is a kind of new cooling technology, utilizing the evaporating of work fluid to cool the stator collector ring of hydro-generator. In this article, the thermodynamic processes of SECS of stator collector ring were analyzed by the second law of thermodynamics. The entropy production and power loss of isolated SECS were analyzed. Based on the distinctive characteristics of SECS, a performance evaluation function was proposed. The influence of heat load on was discussed by simulating. The conclusions provide the theory basis for the application of this new cooling technology.

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Li, Jian Qiang, Dan Dan Chen, He Wang et Xiao Fei Fu. « The Analysis Research of Thermal System of Coal-Fired Power Plant and Examples of Applications ». Advanced Materials Research 614-615 (décembre 2012) : 157–61. http://dx.doi.org/10.4028/www.scientific.net/amr.614-615.157.

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What the paper describes is to develop the performance calculation program and it will be used in the practical unit through analyzing the thermal process in the power plant, which is on the basis of the operation performance of the power plant equipment and the analysis of the calculation method in accordance with the first law of thermodynamics. We can be analyzed through calculating and quantifying the performance of the whole boiler, the turbine, the thermodynamic system and the power plant in detail. The operation quality and the intact degree of unit equipment can be evaluated by the operation personnel according to performance data. Finally, it is going to save energy reduce consumption, and realize the goal of improving level of the unit operation.

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Chubb, Christopher T., Marco Tomamichel et Kamil Korzekwa. « Beyond the thermodynamic limit : finite-size corrections to state interconversion rates ». Quantum 2 (27 novembre 2018) : 108. http://dx.doi.org/10.22331/q-2018-11-27-108.

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Thermodynamics is traditionally constrained to the study of macroscopic systems whose energy fluctuations are negligible compared to their average energy. Here, we push beyond this thermodynamic limit by developing a mathematical framework to rigorously address the problem of thermodynamic transformations of finite-size systems. More formally, we analyse state interconversion under thermal operations and between arbitrary energy-incoherent states. We find precise relations between the optimal rate at which interconversion can take place and the desired infidelity of the final state when the system size is sufficiently large. These so-called second-order asymptotics provide a bridge between the extreme cases of single-shot thermodynamics and the asymptotic limit of infinitely large systems. We illustrate the utility of our results with several examples. We first show how thermodynamic cycles are affected by irreversibility due to finite-size effects. We then provide a precise expression for the gap between the distillable work and work of formation that opens away from the thermodynamic limit. Finally, we explain how the performance of a heat engine gets affected when one of the heat baths it operates between is finite. We find that while perfect work cannot generally be extracted at Carnot efficiency, there are conditions under which these finite-size effects vanish. In deriving our results we also clarify relations between different notions of approximate majorisation.

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Guo, Xinjia, Bing Xu, Zheshu Ma, Yanju Li et Dongxu Li. « Performance Analysis Based on Sustainability Exergy Indicators of High-Temperature Proton Exchange Membrane Fuel Cell ». International Journal of Molecular Sciences 23, n^o 17 (4 septembre 2022) : 10111. http://dx.doi.org/10.3390/ijms231710111.

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Based on finite-time thermodynamics, an irreversible high-temperature proton exchange membrane fuel cell (HT-PEMFC) model is developed, and the mathematical expressions of exergy efficiency, exergy destruction index (EDI), and exergy sustainability indicators (ESI) of HT-PEMFC are derived. According to HT-PEMFC model, the influences of thermodynamic irreversibility on exergy sustainability of HT-PEMFC are researched under different operating parameters that include operating temperatures, inlet pressure, and current density. The results show that the higher operating temperature and inlet pressure of HT-PEMFCs is beneficial to performance improvement. In addition, the single cell performance gradually decreases with increasing current density due to the presence of the irreversibility of HT-PEMFC.

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Wang, Lei, Chonghong Zhan, Jianli Zhang et Xudong Zhao. « The energy and exergy analysis of counter-flow regenerative evaporative cooler ». Thermal Science 23, n^o 6 Part A (2019) : 3615–26. http://dx.doi.org/10.2298/tsci180602304w.

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Recently the regenerative evaporative cooler (REC) has drawn great attention from researchers because it can cool the intake air below the wet-bulb temperature and approaching its dew point temperature. For further understanding of the heat and mass transfer occurred in a counter-flow REC, a novel mathematical model is developed based on the law of energy conservation and the principle of the thermodynamic theory. The proposed mathematical model is validated against experimental data from literature. The parametric study is performed to investigate the performance of the REC under different operating and geometrical conditions. It is found that the exergy destruction and exergy efficiency ratio of the REC are strongly influenced by the intake air velocity, the working to intake air ratio and channel gap, followed by the channel length. The working to intake air ratio choosing from 0.3 to 0.4 is appropriate in order to achieve better thermal performance with permissible level of thermodynamic cost. Moreover, the results obtained in this paper reveal that the best thermal performance does not correspond to the best thermodynamic performance. Thus, both the first and second law of thermodynamics should be considered for a comprehensive analysis.

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Khamooshi, Mehrdad, Kiyan Parham, Mortaza Yari, Fuat Egelioglu, Hana Salati et Saeed Babadi. « Thermodynamic Analysis and Optimization of a High Temperature Triple Absorption Heat Transformer ». Scientific World Journal 2014 (2014) : 1–10. http://dx.doi.org/10.1155/2014/980452.

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First law of thermodynamics has been used to analyze and optimize inclusively the performance of a triple absorption heat transformer operating with LiBr/H2O as the working pair. A thermodynamic model was developed in EES (engineering equation solver) to estimate the performance of the system in terms of the most essential parameters. The assumed parameters are the temperature of the main components, weak and strong solutions, economizers’ efficiencies, and bypass ratios. The whole cycle is optimized by EES software from the viewpoint of maximizing the COP via applying the direct search method. The optimization results showed that the COP of 0.2491 is reachable by the proposed cycle.

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Huang, Dongsheng, Yin Zhang et Yanhong Zheng. « Evaluation of thermal performance of air source heat pump heating system based on electricity equivalent ». Thermal Science, n^o 00 (2022) : 6. http://dx.doi.org/10.2298/tsci210712006h.

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Thermal performance assessment and optimization for energy conversion and utilization systems are of high significance in building energy efficiency. Generally speaking, the evaluation of actual thermodynamic system performance is mainly based on the first law of thermodynamics, with emphasis on the quantity of energy consumption, while ignoring the energy quality. Thus, it results in a one-sided evaluation in the analysis of system energy saving. In this paper, the electricity equivalent is used to analyze and evaluate the air source heat pump (ASHP) heating system under the different working conditions. Moreover, the dynamic thermal performances of three typical space heating devices (radiator, fan coil and radiant floor) are investigated and compared by weighing both energy quantity and quality. The results show that the COP of radiator, fan coil and are radiant floor are 3.00, 3.82 and 4.76, and COEQ are 48.32%, 51.43% and 50.57%, respectively. However, the robustness of its thermal performance is lower than that of radiator and fan coil. This work can provide reference for energy systems assessment and guidance for practical design of building heating systems.

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Mullisen, R. S. « Boil–Freeze–Pop Thermodynamics ». International Journal of Mechanical Engineering Education 30, n^o 2 (avril 2002) : 119–22. http://dx.doi.org/10.7227/ijmee.30.2.3.

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A NASA astronaut's observation of a pan of water placed in a vacuum chamber used for simulated space conditions provided information for this analysis. As the vacuum chamber was depressurized the water was observed to boil violently, then flash freeze, and then ice popped out of the pan. A thermodynamic analysis of the observed behaviour includes phase change cooling, an explanation of the boil—freeze—pop performance and a process path plot on the pressure—volume—temperature diagram that passes through the triple point of water.

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Ujile, Awajiogak Anthony, et Dirina Amesi. « Performance Evaluation of Refrigeration Units in Natural Gas Liquid Extraction Plant ». Journal of Thermodynamics 2014 (25 mars 2014) : 1–7. http://dx.doi.org/10.1155/2014/863408.

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This paper has applied thermodynamics principles to evaluate the reliability of 390 m3/hr natural gas processing plant. The thermodynamics equations were utilized in the evaluation, characterization, and numerical simulation of key process parameters in natural gas liquid extraction plant. The results obtained show the comparison of the coefficient of performance, compression ratio, isentropic work, actual work, electrical power requirements, cooling water consumption in intercoolers, compressor power output, compressor capacity, and isentropic, volumetric, and mechanical efficiency of the two-stage refrigeration unit with a flash gas economizer and these were compared with the designed specifications. The second law of thermodynamics was applied in analyzing the refrigeration unit and the result shows that exergetic losses or lost work due to irreversibility falls within operating limit that is less than 1.0%. Similarly, the performance of expansion turbine (expander) parameters was monitored and the results indicate a considerable decrease in turbine efficiencies as the inlet gas pressure increases resulting in an increased power output of the turbine leading to a higher liquefaction rate.

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Bruno, Nickolaus M., et Matthew R. Phillips. « An Analytical Approach for Computing the Coefficient of Refrigeration Performance in Giant Inverse Magnetocaloric Materials ». Magnetism 2, n^o 1 (13 janvier 2022) : 10–30. http://dx.doi.org/10.3390/magnetism2010002.

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An analytical approach for computing the coefficient of refrigeration performance (CRP) was described for materials that exhibited a giant inverse magnetocaloric effect (MCE), and their governing thermodynamics were reviewed. The approach defines the magnetic work input using thermodynamic relationships rather than isothermal magnetization data discretized from the literature. The CRP was computed for only cyclically reversible temperature and entropy changes in materials that exhibited thermal hysteresis by placing a limit on their operating temperature in a thermodynamic cycle. The analytical CRP serves to link meaningful material properties in first-order MCE refrigerants to their potential work and efficiency and can be employed as a metric to compare the behaviors of dissimilar alloy compositions or for materials design. We found that an optimum in the CRP may exist that depends on the applied field level and Clausius–Clapeyron (CC) slope. Moreover, through a large literature review of NiMn-based materials, we note that NiMn(In/Sn) alloys offer the most promising materials properties for applications within the bounds of the developed framework.

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Nguyen, Trung Hieu, Phuong Nguyen-Tri, Xavier Vancassel et Francois Garnier. « Aero-thermodynamic and chemical process interactions in an axial high-pressure turbine of aircraft engines ». International Journal of Engine Research 20, n^o 6 (21 mai 2018) : 653–69. http://dx.doi.org/10.1177/1468087418772228.

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Precise investigation of aero-thermodynamic and chemical processes relating to environmental precursor pollutants in an aircraft turbine is challenging because of the complexity of transformation processes at high temperature and high pressure. We present here, for the first time, new insights into the study of aero-thermodynamic processes, formation of nitrate and sulfate aerosol precursors, and investigate the influence of chemical processes on aero-thermodynamics. We also shed light on the effect of three-dimensional blade profile, radial spacing, and rotor speed on the performance of a high-pressure turbine. We highlight that flow vortex and the variation of chemical formation which appear in both rear stator blades and rear rotor blades. We found that the chemical processes were affected by the evolution of temperature (maximum of 16.9%) and flow velocity (maximum of 38.8%). Contrary to the conservative one-dimensional and two-dimensional modeling, which provide only the flow trends and flow evolution at cylindrical surface, respectively, our three-dimensional modeling approach offers the possibility of combining information on radial spacing and rotor-speed effect by providing three-dimensional images of spatial-geometry effect on aero-thermodynamic and chemical processes. Quantitatively, the magnitude of change in aero-thermodynamics and nitrogen oxidation may be expected to be up to 17% and 48%, respectively, over a stage of the high-pressure turbine.

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Wan Mohd Zawawi, Wan Akmal Izzati, Khairiyah Mohd Yusof, Nur Fazirah Jumari, Nor Azlinda Azmi et Tengku Nur Zulaikha Tengku Malim Busu. « Implication of Active Learning Techniques in Learning Thermodynamics Energy Conversion using BLOSSOMS Thermodynamics Energy Conversion Video towards Engineering Undergraduates Performance ». International Journal of Emerging Technologies in Learning (iJET) 14, n^o 24 (19 décembre 2019) : 121. http://dx.doi.org/10.3991/ijet.v14i24.12097.

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Utilization of BLOSSOMS Thermodynamics Energy Conversion video to properly incorporate active learning techniques had been shown to increase the students’ performance in learning introductory Thermodynamics topics. In this study, the effectiveness of using BLOSSOMS Thermodynamics Energy Conver-sion video towards students’ learning in a classroom when adopted by lecturers who is not trained in active learning is investigated. Two groups of undergraduate engineering students from a control class and a treatment class were involved in this study. The students from the treatment class were taught by a lecturer using the BLOSSOMS Thermodynamics Energy Conversion video, while the students from control class underwent conventional lecture style. The students were given pre and post inventory tests and their results were analysed using SPSS. It was found that BLOSSOMS Thermodynamics Energy Conversion video without the proper implementation of active learning technique does not have a significant ef-fect on the individual learning gain of the inventory test among students. The uti-lization of the video could be more effective if the instructor is well-trained in ac-tive learning techniques.

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Ma, Xin Ling, Xiang Rui Meng, Xin Li Wei, Jia Chang et Hui Li. « Analysis and Optimization of ORC for Low-Temperature Waste Heat Power Generation ». Advanced Materials Research 383-390 (novembre 2011) : 6614–20. http://dx.doi.org/10.4028/www.scientific.net/amr.383-390.6614.

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This paper presents energy analysis, thermodynamic calculation and exergy analysis for waste heat power generation system of Organic Rankine Cycle based on the first and second laws of thermodynamics. In order to improve system performance, for low-temperature waste heat of 120°C and R245fa organic working fluid, using Aspen Plus software conducted simulation, optimization and improvement. Results from these analyses show that decreasing the expander inlet temperature, increasing inlet pressure of the expander, and adding regenerative heater can increase thermal and exergy efficiencies, at the same time reduce system irreversibility.

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Holubec, Viktor, et Artem Ryabov. « Fluctuations in heat engines ». Journal of Physics A : Mathematical and Theoretical 55, n^o 1 (15 décembre 2021) : 013001. http://dx.doi.org/10.1088/1751-8121/ac3aac.

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Abstract At the dawn of thermodynamics, Carnot’s constraint on efficiency of heat engines stimulated the formulation of one of the most universal physical principles, the second law of thermodynamics. In recent years, the field of heat engines acquired a new twist due to enormous efforts to develop and describe microscopic machines based on systems as small as single atoms. At microscales, fluctuations are an inherent part of dynamics and thermodynamic variables such as work and heat fluctuate. Novel probabilistic formulations of the second law imply general symmetries and limitations for the fluctuating output power and efficiency of the small heat engines. Will their complete understanding ignite a similar revolution as the discovery of the second law? Here, we review the known general results concerning fluctuations in the performance of small heat engines. To make the discussion more transparent, we illustrate the main abstract findings on exactly solvable models and provide a thorough theoretical introduction for newcomers to the field.

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Dukhan, Nihad. « On the worldwide engineering students' meager performance in thermodynamics ». QScience Proceedings 2015, n^o 4 (juin 2015) : 17. http://dx.doi.org/10.5339/qproc.2015.elc2014.17.

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Dukhan, Nihad. « On the worldwide engineering students' meager performance in thermodynamics ». QScience Proceedings 2015, n^o 4 (juin 2015) : 17. http://dx.doi.org/10.5339/qproc.2015.wcee2014.17.

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Akanbi, Olatunde David. « Commentary on the Thermodynamics of a Super-alloy System (AlNi-Cr) Using the Thermocalc Databases ». International Journal of Research and Innovation in Applied Science 08, n^o 02 (2023) : 79–87. http://dx.doi.org/10.51584/ijrias.2023.8201.

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The present study aims to comprehend the thermodynamics of the Al-Ni-Cr superalloy system utilizing the latest Thermocalc 2022b databases. Thermocalc is a software that has a large database which has become vast over the years. The thermodynamic behavior and stability of the system were examined under varying conditions, including temperature and composition. The findings of this study provide crucial insight into the phase behavior and stability of the Al-Ni-Cr superalloy system, which can inform the optimization of its properties and performance for various industrial applications, compared to previous studies and research. The results of this study contribute to a deeper understanding of the thermodynamics of superalloy systems and can be of great benefit to the materials science and engineering communities. The databases used for the binary systems were NIDEMO v2.0 (Nickel Demo database v2.0, including Ni, Cr, and Al - a subset of TCNI) and TCBIN V1.1 (TC Binary Solutions Database, Version 1.0), while for the ternary systems, NIDEMO V2.0 and PURE 5SGTE V5.1 (Pure Elements - Unary Database, Scientific Group Thermodata Europe) were used. The results here demonstrate the great benefits of studying the thermodynamics of this alloy through available database systems and comparing the results with experimental studies.

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Wei, Zhi Guo, Hai Kun Tao et Yong Li. « Optimization Analysis of Ship Steam Power System with Finite-Time Thermodynamics Theory ». Applied Mechanics and Materials 271-272 (décembre 2012) : 1062–66. http://dx.doi.org/10.4028/www.scientific.net/amm.271-272.1062.

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A basic model with both property of thermodynamic and heat transfer is obtained by simplifying the prime process of ship Steam Power System (SPS), which is converted into endoreversible Carnot Cycle by the introduction of mean temperature in the cycle process. The design parameters is analyzed and optimized in the view point of finite time thermodynamics (FTT) and entropy generation minimization. Results show that, the temperature ratio (α) and the heat transfer parameter ratio (β) of heat source and heat sink are two important influence factors of cycle system performance, and the increase of α and decrease of β will redound to the reduction of irreversible loss and enhancement of power output.

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Rangel, V. B., et A. G. S. Almeida. « CASCADE REFRIGERATION SYSTEM FOR LOW TEMPERATURES USING NATURAL FLUIDS ». Revista de Engenharia Térmica 20, n^o 2 (28 juillet 2021) : 20. http://dx.doi.org/10.5380/reterm.v20i2.81783.

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Cascade refrigeration systems work with two or more serial disposed cycles and can obtain internal temperatures below -60°C, which is necessary for several activities in medicine and scientific research. This paper presents a thermodynamic analysis of cascade system refrigeration using natural refrigerant fluids for ultra-low temperatures. These fluids are environmentally friendly refrigerant and are an alternative to hydro chlorofluorocarbons (HCFCs) and to hydrofluorocarbons (HFCs). Energy and exergy analyses were performed using a thermodynamic model based on the law of conservation of mass and also on the first and second laws of thermodynamics. A simulator was developed to assess the technical practicability of this system, considering it running as a real refrigeration cycle. Natural fluids have best performance energetically and environmentally.

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Lou, De Cang, Wen Guo, Zhi Guo Wang et Yong Hong Wang. « Integrated Thermal Management System Design for Advanced Propulsion System ». Applied Mechanics and Materials 232 (novembre 2012) : 723–29. http://dx.doi.org/10.4028/www.scientific.net/amm.232.723.

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Thermal management system (TMS) design is considered to be a key technology for advanced aero engines and supersonic or hypersonic propulsion systems. In this paper, the concepts of coupling flow and thermodynamic networks are proposed for TMS design. In this method, the propulsion system is considered to be a zero-dimensional flow system. Components, subsystems and hence the entire engine system can be modelled using some basic flow and thermodynamics networks. The platform for TMS design, ThermalM, is developed based on this model. As an example, modelling for a Turbine Based Combined Cycle (TBCC) thermal management system is described. Performance of the fuel heat exchanger in the network is discussed in detail. With the TMS design technology, performance of the advanced propulsion system can be analysed.

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Nogueira, E. « Thermodynamic Performance of Boehmite Alumina Nanoparticle Shapes in the Counterflow Double Pipe Heat Exchanger ». Journal of Engineering Sciences 9, n^o 1 (2022) : F1—F10. http://dx.doi.org/10.21272/jes.2022.9(1).f1.

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This work compares a theoretical model with a consolidated numerical model related to the thermodynamic performance of boehmite alumina nanoparticles in different formats in a counterflow double pipe heat exchanger. The shapes of the non-spherical nanoparticles under analysis are platelets, blades, cylindrical, and bricks. The second law of thermodynamics is applied to determine Nusselt number, pressure drop, thermal efficiency, thermal and viscous irreversibilities, Bejan number, and the out temperature of the hot fluid. The entropy generation rates associated with the temperature field and the viscous flow are graphical determined. The numerical model uses the k-ε turbulence model, which requires empirical factors to simulate turbulent viscosity and rate of generation of turbulent kinetic energy. Compatibility between the models was demonstrated. It was shown that the maximum absolute numerical error between the quantities Nusselt number, heat transfer rate, and pressure drop for established and specific conditions is less than 12.5 %.

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Miguel, Antonio F. « Towards an Exergy Analysis of Diffusive and Non-Diffusive Processes in Living Organisms ». Diffusion Foundations 7 (juin 2016) : 177–84. http://dx.doi.org/10.4028/www.scientific.net/df.7.177.

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Living organisms are open dissipative thermodynamic systems that rely on mechano-thermo-electrochemical interactions to survive. Plant physiological processes allow plants to survive by converting solar radiation into chemical energy, and store that energy in form that can be used. Mammals catabolize food to obtain energy that is used to fuel, build and repair the cellular components. The exergy balance is a combined statement of the first and second laws of thermodynamics. It provides insight into the performance of systems. In this paper, exergy balance equations for both mammal’s and green plants are presented and analyzed.

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Amirfakhraei, Amirhossein, Jamshid Khorshidi et Taleb Zarei. « A thermodynamic modeling of 2-bed adsorption desalination to promote main equipment performance ». Journal of Water Reuse and Desalination 11, n^o 1 (5 janvier 2021) : 136–46. http://dx.doi.org/10.2166/wrd.2021.059.

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Abstract Adsorption desalination utilizes the discrete adsorption of the water vapor from the evaporator, and is capable of being discharged to the condenser. This study illuminated an advanced cycle of mass and heat recovery among beds, condensers, and evaporators. Morover, the thermodynamic modeling of adsorption desalination systems (ADS) under different operating conditions was investigated. Furthermore, its effect on the evaporator vapor production and the water vapor adsorption and desorption in the adsorption beds were accounted for. Parenthetically, the mathematical model of ADS thermodynamics was validated with the experimental data. Besides, the advanced ADS modeling was conducted via mass and heat recovery among beds, condensers, and evaporators. In addition to the amount of desalinated water, the time history chart of the equipment applied in the process with and without the thermal and mass recovery is also illustrated. Finally, under such operating conditions, the specific daily water production (SDWP) advanced ADS is 153% higher than conventional ADS.

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Huirem, Boris, et Pradeepta Kumar Sahoo. « Thermodynamic Modeling and Performance Optimization of a Solar-Assisted Vapor Absorption Refrigeration System (SAVARS) ». International Journal of Air-Conditioning and Refrigeration 28, n^o 01 (mars 2020) : 2050006. http://dx.doi.org/10.1142/s2010132520500066.

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A thermodynamic steady-state model for a single-effect lithium bromide–water (LiBr-H2O)-based vapor absorption refrigeration system of 17.5[Formula: see text]kW capacities has been presented using the first and second laws of thermodynamics. The mass, energy and exergy balance equations in each component of the vapor absorption cycle have been fitted into a computer program to carry out the calculation using the thermo-physical properties of the working fluid. The performance parameters such as coefficient of performance (COP), exergy coefficient of performance (ECOP), total exergy destruction (TED), etc. have been evaluated considering different temperatures in generator and evaporator, different LiBr concentrations in the weak and strong LiBr-H2O solution and different solution heat exchanger effectiveness. The model evaluated the optimum performance parameters like COP, ECOP, TED, etc. of the vapor absorption system by using Design Expert-12 software for an application like on-farm cooling or transit storage of fruits and vegetables.

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Chen, L., J. Li et F. Sun. « Heat transfer effect on optimal performance of two-stage thermoelectric heat pumps ». Proceedings of the Institution of Mechanical Engineers, Part C : Journal of Mechanical Engineering Science 221, n^o 12 (1 décembre 2007) : 1635–41. http://dx.doi.org/10.1243/09544062jmes740.

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A model of two-stage semiconductor thermoelectric heat pumps with external heat transfer and internal irreversibility is built. Performance of the heat pump with Newton's heat transfer law is analysed and optimized using the combination of finite-time thermodynamics and non-equilibrium thermodynamics. The analytical formula about heating load versus working electrical current, and the coefficient of performance (COP) versus working electrical current are derived. For the fixed total number of thermoelectric elements, the ratio of number of thermo-electric elements of top stage to the total number of thermoelectric elements is also optimized for maximizing the heating load and the COP of the thermoelectric heat pump. The effects of design factors on the performance are analysed.

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Wang, Zhi Yu, Song Zhou, Ruo Han Li, Cai Ling Li et He Fu Zhang. « Exergetic Cost Analysis of Marine Diesel Engine Waste Heat Recovery System Based on Matrix Model Thermo-Economics ». Advanced Materials Research 744 (août 2013) : 566–70. http://dx.doi.org/10.4028/www.scientific.net/amr.744.566.

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Diesel engine is the main power of the marine vessel, its thermal efficiency is the highest in all thermodynamic engines, but still more than 50% of the energy is not being used, so making full use of the waste heat of the main diesel engine scientifically and effectively, not only reduce the fuel consumption and the shipping cost, but also reduce the value of the ship EEDI effectively. To be able to design and transform the green ship, thermodynamic analyzing of the ship power plant and master the energy utilization of each part is necessary. Raising the efficiency of an energy system is within the domain of thermodynamics. Raising the efficiency cost-effectively (thermo-economics) is a multi-disciplinary problem in which thermodynamics interfaces other disciplines of knowledge which in this particular case are design, manufacture and economics. In this paper, it introduces the analysis method of thermo-economics briefly, the thermal economic analysis of the marine diesel engine waste heat recovery system is taken based on matrix model thermo-economics, and the unit exergetic cost is calculated. Some thermal equipments of the system are showed with the result of the performance evaluation. The results shows that thermo-economics is a promising tool for the analysis of complex energy systems. This method also provides a great prospect for energy system optimizations.

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Ticu, Ionela, et Elena Gogu. « ASSESSMENT OF THE PERFORMANCE A VAPOUR COMPORESSION. REFRIGERATION CYCLE WORKING WITH AMMONIA ». Journal of Marine Technology and Environment 2022, n^o 1 (1 avril 2022) : 84–87. http://dx.doi.org/10.53464/jmte.01.2022.12.

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his paper is a part of the efforts done in order to analyse the performance of vapour compression refrigeration cycles. These technologies are used with a high rate in marine refrigeration and are responsible for important amounts of energy consumptions. The obtained results are indicating the fact that the performance of the cycle is decreased when increasing the condensation temperature and keeping constant the evaporation temperature. Gains in the performance are obtained when degrees of superheating and sub cooling are increased, resulting that the cycle with superheating and sub cooling is superior to the one without these two processes. Ammonia or (R717) is a refrigerant often used on board the ships due to its very good thermodynamic properties. Moreover, the concern regarding the environment and the fact that ammonia is a natural refrigerant, offers to this refrigerant the chance to be adopted in the future plants, on board of new ships. The performance of an ammonia based cycle is discussed in terms of coefficient of performance (COP) and exergy efficiency, the theory of the first and second laws of thermodynamics being fundamental.

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Li, Yong, Xiaoyan Zhu, Yawei Zhai, Jiaping Wang, Wendong Xue, Junhong Chen et Jialin Sun. « Research on High Performance Fe3Si-Si3N4-SiC Composite Used for Blast Furnace ». Open Materials Science Journal 6, n^o 1 (18 janvier 2012) : 1–5. http://dx.doi.org/10.2174/1874088x01206010001.

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Excellent Fe3Si-Si3N4-SiC composites were successfully prepared with FeSi75 and SiC as main starting materials by nitridation reaction(at 1300°C for 8Hrs). The material properties were studied; the ferrosilicon nitridation mechanism was analyzed through chemical thermodynamics; phase composition, microstructure, corrosion resistance of products were also investigated. The results are shown that the comprehensive properties of Fe3Si-Si3N4-SiC are outstanding. The nitridation products are fiber-like α-Si3N4 and rod-like β-Si3N4, which makes better mechanical behavior due to fiber reinforcement; a great deal of Fe3Si intermetallic compounds uniformly distribute in matrix, which is one of the products of Fe-Si nitridation and as a plastic phase forming in grain boundary optimizes the performance of products. Chemical thermodynamic analysis is shown that the fiber-like α-Si3N4 is formed by SiO(g) and N2(g) reaction which also increases the rate of nitridation. Fe3Si-Si3N4-SiC material has high corrosion resistance. Now it has been successfully applied to one 2000M3 domestic steel plant, the blast furnace operation goes well.

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Yang, Hui Shan. « The Influence of Thermal Resistances and Nonperfect Regenerative Losses on the Performance of a Ferroelectric Ericsson Refrigerator ». Advanced Materials Research 1006-1007 (août 2014) : 168–72. http://dx.doi.org/10.4028/www.scientific.net/amr.1006-1007.168.

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Using the finite-time thermodynamics, the influence of thermal resistances and nonperfect regenerative losses on the optimal performance of a ferroelectric Ericsson refrigeration-cycle is analyzed. Based on the thermodynamics properties of ferroelectric materials and a linear heat-transfer law, the inherent regenerative losses in the cycle are calculated and the fundamental optimum relations and other relevant performance parameters are determined. The ecological optimization criterion of the refrigerator is derived. The results obtained here may reveal the general characteristics of the ferroelectric Ericsson refrigeration cycle.

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Xu, Xing, Yu Wu et Na Hu. « Particle Swarm Algorithms with Different Thermodynamics Mechanisms and Performance Comparison ». Information Technology Journal 13, n^o 7 (15 mars 2014) : 1361–65. http://dx.doi.org/10.3923/itj.2014.1361.1365.

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Osara, Jude A., et Michael D. Bryant. « Performance and degradation characterization of electrochemical power sources using thermodynamics ». Electrochimica Acta 365 (janvier 2021) : 137337. http://dx.doi.org/10.1016/j.electacta.2020.137337.

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Rupam, Tahmid Hasan, Md Amirul Islam, Animesh Pal et Bidyut Baran Saha. « Adsorption thermodynamics and performance indicators of selective adsorbent/refrigerant pairs ». Applied Thermal Engineering 175 (juillet 2020) : 115361. http://dx.doi.org/10.1016/j.applthermaleng.2020.115361.

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Adesanya, Samuel O., Ramosheuw S. Lebelo et K. C. Moloi. « Evaluation of Heat Irreversibility in a Thin Film Flow of Couple Stress Fluid on a Moving Belt ». Advances in Mathematical Physics 2018 (1 novembre 2018) : 1–6. http://dx.doi.org/10.1155/2018/6237592.

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This article addresses the inherent heat irreversibility in the flow of a couple stress thin film along a moving vertical belt subjected to free and adiabatic surface. Mathematical analysis for the fluid-governing-equations is performed in detail. For maximum thermal performance and efficiency, the present analysis follows the second law of thermodynamics approach for the evaluation of entropy generation rate in the moving film. With this thermodynamic process, the interconnectivity between variables responsible for energy wastage is accounted for in the thermo-fluid equipment. Results of the analysis revealed the fluid properties that contribute more to energy loss and how the exergy of the system can be restored.

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