Journal of Thermal Engineering最新文献_第2页

Simulation of vapour compression air conditioning system using Al2O3 based nanofluid refrigerant 基于Al2O3纳米流体制冷剂的蒸汽压缩空调系统模拟

Journal of Thermal Engineering Pub Date : 2023-10-17 DOI: 10.18186/thermal.1377210

Mohammed DILAWAR, Adnan QAYOUM

{"title":"Simulation of vapour compression air conditioning system using Al2O3 based nanofluid refrigerant","authors":"Mohammed DILAWAR, Adnan QAYOUM","doi":"10.18186/thermal.1377210","DOIUrl":"https://doi.org/10.18186/thermal.1377210","url":null,"abstract":"The energy crisis, Greenhouse Gas (GHG) emissions, and Chlorofluorocarbon (CFC) emis-sions are major environmental issues at present. It is critical to achieve and reduce emissions and energy consumption through the use of environmentally friendly refrigerants. Utilizing an environmentally friendly refrigerant such as HFC-32 may offer a viable solution to the ozone depletion potential (ODP) and global warming issues. This study examines the effects of aluminium oxide (Al2O3) nanoparticles at volume concentrations of 0.06, 0.08, 0.1, 0.12,  and 0.14% in pure refrigerants such as HFC-32 and R-410a used in air-conditioning systems based on the vapour compression refrigeration cycle. The thermophysical properties of pure and nanorefrigerants have been determined using REFPROP (NIST properties of fluid Refer-ence) and a theoretical formulation model using MATLAB software. The important outcomes of HFC-32 nanorefrigerant show the maximum performance with 0.14% alumina nano addi-tives which results in a 46.14% increase in the coefficient of performance (COP) and massive power savings upto 31.59%. Thermal conductivity exhibited an increase with an increment in nanoparticle concentration. Maximum thermal conductivity of 0.172 W/m-K is recorded  in the case of HFC-32/Al2O3 nanorefrigerant with 0.14% volume concentration. The net re-frigeration effect of pure refrigerants (R410a and HFC-32) is 77% and 79% and on addition of nanorefrigerants to the pure the net refrigeration effect increases to 81.2% and 83.5% for R410a and HFC-32 respectively.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135944356","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

Fossil energy reduction for heating and cooling of buildings using shallow geothermal integrated energy systems – a comprehensive review 利用浅层地热综合能源系统减少建筑物供暖和制冷的化石能源——综合综述

Journal of Thermal Engineering Pub Date : 2023-10-17 DOI: 10.18186/thermal.1377257

Balaji KUMAR

{"title":"Fossil energy reduction for heating and cooling of buildings using shallow geothermal integrated energy systems – a comprehensive review","authors":"Balaji KUMAR","doi":"10.18186/thermal.1377257","DOIUrl":"https://doi.org/10.18186/thermal.1377257","url":null,"abstract":"Ground source heat pumps (GSHP) are a very efficient system for space heating and cooling, and it was established in 1904. GSHPs can minimize the environmental effect of buildings by using the ground as a renewable energy source. The ground will act as a heat sink or heat source. The research collection aims at finding the various possible opportunities for the effec-tive integration of shallow geothermal energy (SGE) to decrease the fossil energy in the built environment and to reduce emission associated with it. The direct utilization of SGE using a ground source heat pump (GSHP) has been reviewed in detail for global north and global south countries, with a primary focus on heating application. The punctual information of results of various authors have been extensively summarized. This review discusses the GSHP installation status, SGE availability, GSHP system simulation, feasibilities, and performance. Worldwide more than one million GSHP systems have been installed, and the system is prev-alent in Europe, the Americas, and Asia. Most of the systems are installed for heating-domi-nated buildings in the global north. This paper also contains the research details pertaining to the last two decades about refrigerants and compressors for the development of GSHP. Finally, the feasibility study and the performance of the GSHP unit for different climatic conditions are reviewed and it is found that the technique is more feasible for cold and dry climatic con-ditions. This paper highlights the recent research findings and a potential gap in the above components for further research and development.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135944361","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

Performance enhancement of stepped solar still coupled with evacuated tube collector 真空管集热器耦合阶梯式太阳能蒸馏器的性能提升

Journal of Thermal Engineering Pub Date : 2023-10-17 DOI: 10.18186/thermal.1372168

Bhushan PATIL, Jitendra HOLE, Sagar WANKHEDE

{"title":"Performance enhancement of stepped solar still coupled with evacuated tube collector","authors":"Bhushan PATIL, Jitendra HOLE, Sagar WANKHEDE","doi":"10.18186/thermal.1372168","DOIUrl":"https://doi.org/10.18186/thermal.1372168","url":null,"abstract":"The provision of fresh water is the most important problem in developing countries. With the rising need for fresh water, it is vital to look for other sources. Solar energy is still one of the most essential and technically feasible applications of the sun. There are numerous varieties of solar stills; the basin type is the most basic and well-proven. The biggest disadvantage of a tra-ditional basin solar still is that it produces very little distilled water per unit area. Solar distilla-tion is one of the most basic method to remove pollutants including heavy metals, dust, salts, and microorganisms from water. When compared to rainwater, it produces more clean water. Using solar distillation technology, sea water can be converted to fresh water. In this study, a solar still with a single basin is compared against a concentrator with evacuated tubes and a stepped basin solar still to see which one produces the most output with the least amount of energy. The four cases are analyzed, and it is discovered that the productivity of case 1: a solar still with a single slope with constant flow rate is 1.05kg/m2 and the maximum temperature ob-tained during this case is 49.0°C at 3:00 PM. The productivity for case 2: single slope solar with secondary stepped basin is 1.32kg/m2 while the maximum temperature is about 61.8°C at 3:00 PM. The productivity of case 3: a solar still with a single slope linked to a compound parabolic concentrator is 1.47kg/m2 with a maximum temperature of 62.4°C at around 3:00 PM. The output of Case 4: a solar still with a single slope with secondary stepped basin and compound parabolic concentrator is 1.72kg/m2 with a maximum temperature of 70.2°C obtained at 3:00 PM. The efficiency of a solar still with a single slope and a secondary stepped basin with a compound parabolic concentrator is 63.8 % higher than the reference case.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135944316","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

Surface modification techniques for cooling by impinging jets-a review 冲击射流冷却表面改性技术综述

Journal of Thermal Engineering Pub Date : 2023-10-17 DOI: 10.18186/thermal.1377253

Supern SWAPNIL, Ajoy DEBBARMA

{"title":"Surface modification techniques for cooling by impinging jets-a review","authors":"Supern SWAPNIL, Ajoy DEBBARMA","doi":"10.18186/thermal.1377253","DOIUrl":"https://doi.org/10.18186/thermal.1377253","url":null,"abstract":"The following paper is a review of the recent published literature on these three techniques for heat transfer augmentation. With global trend of the miniaturization of today’s systems and the rapid development due to innovative equipment on a rise, the associated heat generation rates are increasing. As a result, the need to develop techniques to achieve faster and efficient cooling are also increasing., Heat transfer by impinging jets poses a good and economical solution to this problem since, among all the processes used for heat removal, heat transfer by impinging jets have the highest rates associated with them. Although, the heat generation rates have increased over period of time, jet impingement is in the industrial use for quite a long time and is still relevant for the field. This is because overtime the impingement heat transfer effectiveness has been improved by various innovations. Innovations such as surface modifi-cations, use of flow control techniques etc. The modifications reported had seen actual use of them in industries, thus bringing more interest of the researchers towards them. The need to achieve higher heat transfer rates and efficient working of the systems is still seeing numerous interactions pertaining to surface modifications integrated with jet impingement reported on them. Primarily, the use of various types of extended surfaces such as pin fins, plate fins, ribs etc., inducing the roughness elements on the surface by employing dimples, protrusions etc., applying specific surface coatings found a plethora of research work reported on them. For any work, it is necessary to study these modifications and their interactions in details. This paper thus presents the above stated three surface modifications in detail.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135944359","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

Exergoeconomic study of reheat combined cycle configurations using steam and ammonia-water mixture for bottoming cycle parameters 以蒸汽和氨水混合物为底循环参数的再热联合循环结构的运行经济性研究

Journal of Thermal Engineering Pub Date : 2023-10-17 DOI: 10.18186/thermal.1376826

Mayank MAHESHWARI, Onkar SINGH

引用次数: 0

CFD modelling of the microclimate of a cultivated greenhouse: A validation study between experimental and numerical results 栽培温室小气候的CFD模拟:实验与数值结果的验证研究

Journal of Thermal Engineering Pub Date : 2023-10-17 DOI: 10.18186/thermal.1370719

Soumaïla TIGAMPO, Sami KOOLI, Nizar Ben SALAH, Walid FOUDHIL, Reda ERRAIS, Sadok Ben JABRALLAH, Vincent SAMBOU

{"title":"CFD modelling of the microclimate of a cultivated greenhouse: A validation study between experimental and numerical results","authors":"Soumaïla TIGAMPO, Sami KOOLI, Nizar Ben SALAH, Walid FOUDHIL, Reda ERRAIS, Sadok Ben JABRALLAH, Vincent SAMBOU","doi":"10.18186/thermal.1370719","DOIUrl":"https://doi.org/10.18186/thermal.1370719","url":null,"abstract":"In this work, we present the validation of a numerical model of a greenhouse thermally in-sulated on three sides with a tomato crop. A CFD software (Ansys-Fluent) was used to solve the numerical model. The discrete ordinate model was included to solve the radiative trans-fer equation. The results of the numerical model were compared with the values of air tem-perature observations at different points in the greenhouse. Good agreement was obtained between the simulated and measured values, with coefficients of determination R2 = 0.77, R2 = 0.84, R2 = 0.99, and R2 = 0.89 for the temperatures of the points 10 cm, 80 cm, and 210 cm above the ground and the average temperature in the greenhouse, respectively. A third-order polynomial curve was drawn between the simulated and measured values of relative humidity in the greenhouse. These R2 values are 0.9786 and 0.7165, the simulated and measured relative humidity, respectively. The simulation results showed low velocity values with an average of 0.525 m/s located between 1.5 m and 2 m from the ground.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135944813","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

An experimental investigation to study the performance characteristics of heat pipe using aqueous hybrid nanofluids 采用水相混合纳米流体研究热管的性能特性

Journal of Thermal Engineering Pub Date : 2023-10-17 DOI: 10.18186/thermal.1372260

Harshit PANDEY, Naveen Kumar GUPTA, Sanjay AGARWAL

{"title":"An experimental investigation to study the performance characteristics of heat pipe using aqueous hybrid nanofluids","authors":"Harshit PANDEY, Naveen Kumar GUPTA, Sanjay AGARWAL","doi":"10.18186/thermal.1372260","DOIUrl":"https://doi.org/10.18186/thermal.1372260","url":null,"abstract":"The steady-state performance characteristics of a mesh-wick heat pipe were investigated ex- perimentally across a heat load range of 25W-100W incorporating DI water, Al2O3 nanofluids, and Al2O3+GO hybrid nanofluids respectively. All the nano-suspensions were prepared fol-lowing the two-step preparation method. Out of all the prepared Al2O3 nanofluids, 1.0 vol.% Al2O3 nanofluid exhibited the highest reduction in adiabatic vapor temperature. The hybrid combination of 75% Al2O3 +25% GO nanofluid in the heat pipe resulted in a maximum dec-rement of about 21.4%, and 59.5% in the average evaporator temperature, and thermal resis-tance respectively while offering maximum thermal efficiency enhancement of about 31.4% relative to the base fluid. The 75% Al2O3+25% GO hybrid nanofluid in the heat pipe offered the least thermal resistance at a gravity-assisted inclination of 60º. The current study contem- plates the most favourable hybrid combination of Al2O3 and GO nanoparticles for its incor-poration in the heat pipe and tries to identify the underlying reasons behind the performance characteristics achieved using hybrid nanofluids and finally projects the future research scope.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135944318","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

Investigation of thermo-rheological properties of Fe3O4/Ethylene glycol nanofluid in a square cavity 方形腔中Fe3O4/乙二醇纳米流体热流变特性研究

Journal of Thermal Engineering Pub Date : 2023-10-17 DOI: 10.18186/thermal.1377221

Mohammad KAMRAN, Adnan QAYOUM

{"title":"Investigation of thermo-rheological properties of Fe3O4/Ethylene glycol nanofluid in a square cavity","authors":"Mohammad KAMRAN, Adnan QAYOUM","doi":"10.18186/thermal.1377221","DOIUrl":"https://doi.org/10.18186/thermal.1377221","url":null,"abstract":"Many fluids used in heat transfer and transport phenomena restrict the effectiveness of heat exchange equipment on account of their low thermal conductivity. Using nanofluids, the ef-fectiveness of heat exchange equipment is enhanced by many folds. The use of magnetic nano-fluids for heat transfer generates a prospect of regulating flow and controlling the thermal and transport properties particularly the thermal conductivity and viscosity using an externally applied magnetic field. The present study involves synthesis of oleic acid-coated magnetic nanofluids at varying concentrations of 0 to 0.643% by volume, measurement of thermal conductivity, rheological properties and corresponding numerical simulation of Nanofluid in a heated square cavity. The thermal conductivity measurement have been carried out by transient hot-wire method using KD2-pro at varying concentrations of solid phase. The re-sults show a significant increase in thermal conductivity with increase in particle concentra-tion. Rheological measurements show variation in viscosity with shear rate, temperature and concentration. Moreover, it has been found that at low particle loading magnetic nanofluids exhibited Newtonian behavior unlike non-Newtonian behavior at increased concentration. Numerical simulation of the magnetic nanofluid in the heated square cavity demonstrates the immense potential of augmentation of heat transfer coefficient using such fluids.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135944360","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

Temperature effect in the energy degradation of photovoltaic power system 光伏发电系统能量退化中的温度效应

Journal of Thermal Engineering Pub Date : 2023-10-17 DOI: 10.18186/thermal.1370726

Yasseen AJ ALMAHDAWI, Mohammed KH ABBAS, Ahmed AL-SAMARI, Nazar ALDABASH, Saadoon Abdul HAFEDH

引用次数: 0

Energy and production analysis of a dairy milk factory: A case of study 某乳品厂能源与生产分析:个案研究

Journal of Thermal Engineering Pub Date : 2023-10-17 DOI: 10.18186/thermal.1370731

Öznur ÖZTUNA TANER

{"title":"Energy and production analysis of a dairy milk factory: A case of study","authors":"Öznur ÖZTUNA TANER","doi":"10.18186/thermal.1370731","DOIUrl":"https://doi.org/10.18186/thermal.1370731","url":null,"abstract":"This study illustrates a factory’s production efficiency by demonstrating its energy efficiency in the dairy milk industry. Determining the thermal energy to save energy enhances the prof-itability of the factory. The aim of this study is to conduct a thermal energy and production analysis of a dairy milk factory based on annual production. This study intends to make the conclusions more realistic by using production and energy data dependability analysis. The overall power consumption for the thermal and electric energy processes was found to be as 180,520 [W]. The target-specific energy consumption value was computed for Case 1 as 6,352.14 [MJ/t], for Case 2 as 5,898.67 [MJ/t], and for Case 3 as 5,445.21 [MJ/t]. The annual thermal (steam boiler) and electrical energy expenditures were obtained, with 315.87 [kW] of thermal (steam) energy and 80.98 [kW] of electrical energy. The total thermal and electri-cal energy reached 396.85 [kW]. Despite the factory’s expenditure on thermal and electrical energy, the energy efficiency was determined to be as 45.5%. The input energy was obtained to be 374.24 [kW] in Case 1, 356.33 [kW] in Case 2, and 342.08 [kW] in Case 3. The energy efficiency was calculated as 48.2 [%] for Case 1, 50.7 [%] for Case 2, and 52.8 [%] for Case 3. This study, which is expected to inspire future research, is also likely to assist livestock and agriculture in the energy field. The novelty of this study is that optimizing product efficiency and energy consumption in the production of milk and dairy products positively increases the energy efficiency of factories.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135944801","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