Pub Date : 2023-10-17DOI: 10.18186/thermal.1377257
Balaji KUMAR
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.
{"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":"206 1","pages":"0"},"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}
Pub Date : 2023-10-17DOI: 10.18186/thermal.1372168
Bhushan PATIL, Jitendra HOLE, Sagar WANKHEDE
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.
{"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":"39 1","pages":"0"},"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}
Pub Date : 2023-10-17DOI: 10.18186/thermal.1377253
Supern SWAPNIL, Ajoy DEBBARMA
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.
{"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":"3 1","pages":"0"},"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}
Pub Date : 2023-10-17DOI: 10.18186/thermal.1376826
Mayank MAHESHWARI, Onkar SINGH
The use of combined cycle power plants though had led the pathway to maximize the fuel en-ergy utilization but the part-load operation of these plants is of concern. In this work, an exer-goeconomic comparison of 11 different reheat combined cycle arrangements hasbeen carried out under their part-load operations for varying bottoming cycle parametersnamely steam-bleedfraction, deaerator pressure,separator temperature, absorber pressure, and condenser pressure.The results depict that the absorber has the highest exergy destruction with second law efficiency of 23.55% at thepart load of 25% for the combined cycle power plant having high pressure drum with steam as working fluid and low pressure drum with ammonia-wa-ter as working fluid. The comparison also shows the highest cost of electricity production as 0.1243USD/kWh for the combined cycle power plant having ammonia-water as working fluid in bottoming cycle and operating at part load of 25%. While the minimum price of electricity produced is 0.05USD/kWh at 25% part load for CCPP having double pressure HRVG’s at condenser pressure of 0.09 bar.
{"title":"Exergoeconomic study of reheat combined cycle configurations using steam and ammonia-water mixture for bottoming cycle parameters","authors":"Mayank MAHESHWARI, Onkar SINGH","doi":"10.18186/thermal.1376826","DOIUrl":"https://doi.org/10.18186/thermal.1376826","url":null,"abstract":"The use of combined cycle power plants though had led the pathway to maximize the fuel en-ergy utilization but the part-load operation of these plants is of concern. In this work, an exer-goeconomic comparison of 11 different reheat combined cycle arrangements hasbeen carried out under their part-load operations for varying bottoming cycle parametersnamely steam-bleedfraction, deaerator pressure,separator temperature, absorber pressure, and condenser pressure.The results depict that the absorber has the highest exergy destruction with second law efficiency of 23.55% at thepart load of 25% for the combined cycle power plant having high pressure drum with steam as working fluid and low pressure drum with ammonia-wa-ter as working fluid. The comparison also shows the highest cost of electricity production as 0.1243USD/kWh for the combined cycle power plant having ammonia-water as working fluid in bottoming cycle and operating at part load of 25%. While the minimum price of electricity produced is 0.05USD/kWh at 25% part load for CCPP having double pressure HRVG’s at condenser pressure of 0.09 bar.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135944497","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}
Pub Date : 2023-10-17DOI: 10.18186/thermal.1370719
Soumaïla TIGAMPO, Sami KOOLI, Nizar Ben SALAH, Walid FOUDHIL, Reda ERRAIS, Sadok Ben JABRALLAH, Vincent SAMBOU
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.
{"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":"15 1","pages":"0"},"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}
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.
{"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":"75 1","pages":"0"},"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}
Pub Date : 2023-10-17DOI: 10.18186/thermal.1377221
Mohammad KAMRAN, Adnan QAYOUM
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.
{"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":"1 1","pages":"0"},"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}
Pub Date : 2023-10-17DOI: 10.18186/thermal.1370726
Yasseen AJ ALMAHDAWI, Mohammed KH ABBAS, Ahmed AL-SAMARI, Nazar ALDABASH, Saadoon Abdul HAFEDH
The modelling of output power for the photovoltaic system is essential for system design and local resource prediction. Accurate photovoltaic power modelling the foremost vital issue is systems efficiency analysis. The temperature plays the main role in the energy degradation of the photovoltaic systems, especially in the host sites. In this paper, experimental and theoreti-cal investigation into the photovoltaic module energy degradation due to temperature effects. This work objectives to investigate the photovoltaic power generated due to the ambient tem-perature effect. The presented results show that the ambient temperature has positive effects on the photovoltaic module energy production during the winter period and negative effects during the summer period. For the proposed photovoltaic system with a capacity of 2.97 kWp the expected theoretical annual energy production by about 554.01 kWh while the annual experiment production was l493.73 kWh. The novelty of the work is to estimate the energy losses due to the ambient temperature effect on the photovoltaic energy production.
{"title":"Temperature effect in the energy degradation of photovoltaic power system","authors":"Yasseen AJ ALMAHDAWI, Mohammed KH ABBAS, Ahmed AL-SAMARI, Nazar ALDABASH, Saadoon Abdul HAFEDH","doi":"10.18186/thermal.1370726","DOIUrl":"https://doi.org/10.18186/thermal.1370726","url":null,"abstract":"The modelling of output power for the photovoltaic system is essential for system design and local resource prediction. Accurate photovoltaic power modelling the foremost vital issue is systems efficiency analysis. The temperature plays the main role in the energy degradation of the photovoltaic systems, especially in the host sites. In this paper, experimental and theoreti-cal investigation into the photovoltaic module energy degradation due to temperature effects. This work objectives to investigate the photovoltaic power generated due to the ambient tem-perature effect. The presented results show that the ambient temperature has positive effects on the photovoltaic module energy production during the winter period and negative effects during the summer period. For the proposed photovoltaic system with a capacity of 2.97 kWp the expected theoretical annual energy production by about 554.01 kWh while the annual experiment production was l493.73 kWh. The novelty of the work is to estimate the energy losses due to the ambient temperature effect on the photovoltaic energy production.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135944815","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}
Pub Date : 2023-10-17DOI: 10.18186/thermal.1377200
Ahmet ŞUMNU, İbrahim GÜZELBEY
In the present study, missile aerodynamic analysis is performed using different wing config-urations at subsonic and transonic speeds. The wing is critical component in point of aero-dynamic efficiency for a missile that speed is especially closer to transonic level because of flow separation. Flow on the wings may adversely effect tailfins of missile at high speed since it may cause vortex generation and flow disturbances. There are few studies that investigate the missile wing using different configurations at critical speeds when examined the previ-ous studies. Therefore, in this study, three different wing configurations are investigated and aerodynamic performance is compared with each other at 0.7 and 0.9 Mach numbers and 5° angle of attack (AoA). In beginning of this study, missile model with only tailfins is selected from previous study that contains experimental data. Because the experimental data for the selected missile model are available at supersonic speeds, the aerodynamic analysis to verify the solutions is carried out at supersonic speeds. After wing is mounted to the selected missile, aerodynamic analysis is carried out using three different wing configurations that are Tapered Leading Edge, Tapered Trailing Edge, and Double Tapered wings. Lift to drag ratio (CL/CD) is calculated to compare wing configurations and it is concluded that Tapered Leading Edge wing configuration shows higher performance then other wing configurations. CL/CD values are 2.327, 2.306, 2.303 at 0.7 Mach number and 2.45, 2.429, 2.423 at 0.9 Mach number for Tapered Leading Edge, Tapered Trailing Edge, and Double Tapered, respectively. When the results are compared each other, CL/CD values at 0.9 Mach number is higher about % 5.28, %5.33 and %5.21 than the CL/CD values at 0.7 Mach number for missile with Tapered Leading Edge, Tapered Trailing Edge, and Double Tapered, respectively.
{"title":"The effects of different wing configurations on missile aerodynamics","authors":"Ahmet ŞUMNU, İbrahim GÜZELBEY","doi":"10.18186/thermal.1377200","DOIUrl":"https://doi.org/10.18186/thermal.1377200","url":null,"abstract":"In the present study, missile aerodynamic analysis is performed using different wing config-urations at subsonic and transonic speeds. The wing is critical component in point of aero-dynamic efficiency for a missile that speed is especially closer to transonic level because of flow separation. Flow on the wings may adversely effect tailfins of missile at high speed since it may cause vortex generation and flow disturbances. There are few studies that investigate the missile wing using different configurations at critical speeds when examined the previ-ous studies. Therefore, in this study, three different wing configurations are investigated and aerodynamic performance is compared with each other at 0.7 and 0.9 Mach numbers and 5° angle of attack (AoA). In beginning of this study, missile model with only tailfins is selected from previous study that contains experimental data. Because the experimental data for the selected missile model are available at supersonic speeds, the aerodynamic analysis to verify the solutions is carried out at supersonic speeds. After wing is mounted to the selected missile, aerodynamic analysis is carried out using three different wing configurations that are Tapered Leading Edge, Tapered Trailing Edge, and Double Tapered wings. Lift to drag ratio (CL/CD) is calculated to compare wing configurations and it is concluded that Tapered Leading Edge wing configuration shows higher performance then other wing configurations. CL/CD values are 2.327, 2.306, 2.303 at 0.7 Mach number and 2.45, 2.429, 2.423 at 0.9 Mach number for Tapered Leading Edge, Tapered Trailing Edge, and Double Tapered, respectively. When the results are compared each other, CL/CD values at 0.9 Mach number is higher about % 5.28, %5.33 and %5.21 than the CL/CD values at 0.7 Mach number for missile with Tapered Leading Edge, Tapered Trailing Edge, and Double Tapered, respectively.","PeriodicalId":45841,"journal":{"name":"Journal of Thermal Engineering","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135944358","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}
Pub Date : 2023-10-17DOI: 10.18186/thermal.1370731
Öznur ÖZTUNA TANER
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.
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