Thermodynamics and Energy Engineering最新文献

Fuel Cells: Alternative Energy Sources for Stationary, Mobile and Automotive Applications 燃料电池:固定、移动和汽车应用的替代能源

Thermodynamics and Energy Engineering Pub Date : 2020-06-24 DOI: 10.5772/intechopen.93032

I. Petreanu, M. Dragan, Silviu-Laurentiu Badea

引用次数: 2

Energy Storage in PCM Wall Used in Buildings’ Application: Opportunity and Perspective PCM墙体储能在建筑中的应用:机遇与展望

Thermodynamics and Energy Engineering Pub Date : 2020-06-05 DOI: 10.5772/intechopen.92557

Majdi Hazami, Farah Mehdaoui, Hichem Taghouti, M. Noro, R. Lazzarin, A. Guizani

{"title":"Energy Storage in PCM Wall Used in Buildings’ Application: Opportunity and Perspective","authors":"Majdi Hazami, Farah Mehdaoui, Hichem Taghouti, M. Noro, R. Lazzarin, A. Guizani","doi":"10.5772/intechopen.92557","DOIUrl":"https://doi.org/10.5772/intechopen.92557","url":null,"abstract":"This chapter deals with the investigation of the effect of a PCM wall on building indoor thermal comfort. To achieve this objective, an experimental framework was installed in the laboratory of thermal processes in Borj Cedria, Tunisia, which is essentially composed of a test cell having the dimension (0.5, 0.5, 0.5 m3) conceived with a new structure of wallboards. One of the sides of the test cell is a cavity filled with PCM-27, which represents the PCM wall. A numerical investigation by using specific FORTRAN program was also achieved to solve the energy and the exergy mathematic relations to evaluate the PCM wall performances. TRNSYS simulation program was also achieved to simulate the behavior of the integration of the PCM wall in a typical modern house according to Tunisian scenario. It is found that during the hottest period of the day, the temperature of the tested room with PCM wall achieves 25°C, while that without PCM wall exceeds 27°C. During the night, the temperature of the tested room, with PCM wall, decreases in the value of 20°C. It was also found that during the night, the kid's room with PCM wall is reduced by 8°C.","PeriodicalId":173761,"journal":{"name":"Thermodynamics and Energy Engineering","volume":"148 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129047537","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Water Desalination Using PCM to Store Solar Energy 利用PCM储存太阳能进行海水淡化

Thermodynamics and Energy Engineering Pub Date : 2020-05-20 DOI: 10.5772/intechopen.92597

P. Kulkarni

{"title":"Water Desalination Using PCM to Store Solar Energy","authors":"P. Kulkarni","doi":"10.5772/intechopen.92597","DOIUrl":"https://doi.org/10.5772/intechopen.92597","url":null,"abstract":"The rising water pollution levels and depleting freshwater sources have formed a delirious inverse proportionality for which the cause is human and effect is also on humanity. A possible solution to this problem is harnessing solar energy to engender thermal energy for solar distillation. Thus solar distillation is one of the potential solutions to asses both the ever-increasing demands for clean water and the inquisition for finding eco-friendly techniques to yield the water. This analysis was undertaken to discover the possible utilization of phase change material on solar distillation in double-slope solar still. The equipment that performs distillation is called \"Solar Still.\" A phase change material (PCM) is a substance that either releases or absorbs energy comparable to the sensible heat during its phase transition to provide useful heat/cooling. Examples of PCM include phenol, paraffin, salt hydrate, and fatty acid. The experiment includes a blank distillate output without PCM, followed by possible optimization on the designed solar still. Solar distillation was performed in the improved solar still with varying types of PCMs. A theoretical model discerning the above phenomena and experiments were performed on the solar still. It was reported that for the yield maximum of water distillate with PCM (Phenol--5 cm) is 370 mL and without PCM is 345 mL, showing a 7.2% increase.","PeriodicalId":173761,"journal":{"name":"Thermodynamics and Energy Engineering","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131998458","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Lithium Recovery from Brines Including Seawater, Salt Lake Brine, Underground Water and Geothermal Water 从盐水中回收锂，包括海水、盐湖盐水、地下水和地热水

Thermodynamics and Energy Engineering Pub Date : 2020-01-21 DOI: 10.5772/intechopen.90371

Samadiy Murodjon, Xiaoping Yu, Mingli Li, J. Duo, T. Deng

引用次数: 18

Fuel Cells as a Source of Green Energy 燃料电池作为一种绿色能源

Thermodynamics and Energy Engineering Pub Date : 2020-01-08 DOI: 10.5772/intechopen.89736

Rabea Q. Nafil, Munaf S. Majeed

引用次数: 3

Einstein’s Equation in Nuclear and Solar Energy 爱因斯坦的核能和太阳能方程

Thermodynamics and Energy Engineering Pub Date : 2019-12-19 DOI: 10.5772/intechopen.90574

A. M. Măgurean, O. Pop, A. Pocola, A. Șerban, Mugur C. Balan

引用次数: 2

Improving Heat-Engine Performance by Employing Multiple Heat Reservoirs 采用多热源提高热机性能

Thermodynamics and Energy Engineering Pub Date : 2019-12-13 DOI: 10.5772/INTECHOPEN.89047

Jack Denur

引用次数: 1

Improving Heat-Engine Performance via High-Temperature Recharge 通过高温充电提高热机性能

Thermodynamics and Energy Engineering Pub Date : 2019-11-25 DOI: 10.5772/INTECHOPEN.89913

Jack Denur

{"title":"Improving Heat-Engine Performance via High-Temperature Recharge","authors":"Jack Denur","doi":"10.5772/INTECHOPEN.89913","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.89913","url":null,"abstract":"Perfect (reversible) cyclic heat engines operate at Carnot efficiency. Perfect reversible) nonheat engines and noncyclic heat engines operate at unit (100%) efficiency. But a usually necessary, although not always sufficient, requirement to achieve reversibility is that an engine must operate infinitely slowly, i.e., quasi-statically. And infinitely slow operation, which implies infinitesimally small power output, is obviously impractical. Most real heat engines operate, if not at maximum power output, then at least closer to maximum power output than to maximum efficiency. Endoreversible heat engines delivering maximum power output operate at Curzon-Ahlborn efficiency. Irrespective of efficiency, engines' work outputs are in almost all cases totally frictionally dissipated as heat immediately (e.g., an automobile operating at constant speed) or on short time scales. But if a heat engine's work output must be frictionally dissipated, it is best to dissipate it not into the cold reservoir but at the highest practicable temperature. We dub this as high-temperature recharge (HTR). This is not always practicable. But if it is practicable, it can yield improved heat-engine performance. We discuss improvements of the Carnot and Curzon-Ahlborn efficiencies achievable via HTR, and show consistency with the First and Second Laws of Thermodynamics. We reply to criticisms of HTR.","PeriodicalId":173761,"journal":{"name":"Thermodynamics and Energy Engineering","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116477751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Fuel Cell Thermodynamics 燃料电池热力学

Thermodynamics and Energy Engineering Pub Date : 2019-11-22 DOI: 10.5772/intechopen.90141

L. Khotseng

{"title":"Fuel Cell Thermodynamics","authors":"L. Khotseng","doi":"10.5772/intechopen.90141","DOIUrl":"https://doi.org/10.5772/intechopen.90141","url":null,"abstract":"Thermodynamics is the study of energy change from one state to another. The predictions that can be made using thermodynamic equations are essential for understanding fuel cell performance, as a fuel cell is an electrochemical device that converts the chemical energy of a fuel and an oxidant gas into electrical energy. When a fuel cell is operating, some of the input is used to create electrical energy, but another portion is converted into thermal energy, depending on the type of fuel cell. Based on the first and second laws of thermodynamics, one can write down thermodynamic potentials to specify how energy can be transferred from one form to another. This chapter examines how electrical energy and thermal energy are transferred in the hydrogen fuel cell system. It also defines how reversible fuel cell voltages, which are the maximum fuel cell performances, are affected by departures from the standard state. Basic thermodynamic concepts allow one to predict states of the fuel cell system, including the potential, temperature, pressure, volume and moles of a fuel cell. The specific topics explored in this chapter include enthalpy, entropy, specific heat, Gibbs free energy, net output voltage irreversible losses in fuel cells and fuel cell efficiency.","PeriodicalId":173761,"journal":{"name":"Thermodynamics and Energy Engineering","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132099455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

How to Build Simple Models of PEM Fuel Cells for Fast Computation 如何建立快速计算的PEM燃料电池简单模型

Thermodynamics and Energy Engineering Pub Date : 2019-11-22 DOI: 10.5772/intechopen.89958

J. Deseure

引用次数: 0