Hamza Saeed, M. Mahmood, Hassan Nazir, A. Waqas, Naveed Ahmed, Majid Ali, Abdul Haseeb, M. Sajid
Rapid population growth and increasing energy demand in developing countries are the key drivers behind rising concerns such as energy poverty and environmental degradation. Harnessing solar energy can help the developing countries inch closer to sustainable economic growth. This paper presents the performance analysis of a solar water heating system based on an evacuated flat plate collector (EFPC). EFPCs offer higher optical performance and lower thermal losses in comparison with conventional solar collectors. In this study, a multi-parametric analysis provides the guidelines for the design and optimization of a novel low vacuum EFPC system under ambient conditions, for domestic hot water (DHW) applications. A small-scale solar thermal collector system based on a low vacuum (17.5 – 20 kPa) EFPC of a total area of 4.0 m2 is designed and installed. The system is coupled with a storage tank comprising of the helical copper coil configuration inside the tank, which is used as a heat exchanger from primary loop to secondary loop. A series of real-time experiments are performed under ambient conditions from December to April. The thermal efficiency of the EFPCs reaches a maximum value of 73.2%, with the glycol-water mixture as a heat transfer fluid at an inlet temperature of 31.2 °C, when the ambient temperature is 15.3 °C, average irradiance is 679.2 Wm-2, and vacuum pressure is 20 kPa. For this duration, the exergy efficiency reaches a peak value of 16%. This EFPC system provides 100 liters of hot water at 57-69 °C per day for DHW consumption when the average ambient temperature is 24 °C. The overall results highlight the potential of EFPCs for hot water applications. Furthermore, an efficiently optimized EFPC system can also be used for space heating during the winter season.
{"title":"Performance Evaluation of an Evacuated Flat Plate Collector System for Domestic Hot Water Applications","authors":"Hamza Saeed, M. Mahmood, Hassan Nazir, A. Waqas, Naveed Ahmed, Majid Ali, Abdul Haseeb, M. Sajid","doi":"10.1115/1.4056790","DOIUrl":"https://doi.org/10.1115/1.4056790","url":null,"abstract":"\u0000 Rapid population growth and increasing energy demand in developing countries are the key drivers behind rising concerns such as energy poverty and environmental degradation. Harnessing solar energy can help the developing countries inch closer to sustainable economic growth. This paper presents the performance analysis of a solar water heating system based on an evacuated flat plate collector (EFPC). EFPCs offer higher optical performance and lower thermal losses in comparison with conventional solar collectors. In this study, a multi-parametric analysis provides the guidelines for the design and optimization of a novel low vacuum EFPC system under ambient conditions, for domestic hot water (DHW) applications. A small-scale solar thermal collector system based on a low vacuum (17.5 – 20 kPa) EFPC of a total area of 4.0 m2 is designed and installed. The system is coupled with a storage tank comprising of the helical copper coil configuration inside the tank, which is used as a heat exchanger from primary loop to secondary loop. A series of real-time experiments are performed under ambient conditions from December to April. The thermal efficiency of the EFPCs reaches a maximum value of 73.2%, with the glycol-water mixture as a heat transfer fluid at an inlet temperature of 31.2 °C, when the ambient temperature is 15.3 °C, average irradiance is 679.2 Wm-2, and vacuum pressure is 20 kPa. For this duration, the exergy efficiency reaches a peak value of 16%. This EFPC system provides 100 liters of hot water at 57-69 °C per day for DHW consumption when the average ambient temperature is 24 °C. The overall results highlight the potential of EFPCs for hot water applications. Furthermore, an efficiently optimized EFPC system can also be used for space heating during the winter season.","PeriodicalId":17124,"journal":{"name":"Journal of Solar Energy Engineering-transactions of The Asme","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49035504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper aims to investigate the transient behavior of a salinity gradient solar pond(SGSP) under Mediterranean climate. For this propose, a 2D numerical model is developed in which the absorption of solar radiation by different layers of saline water, the wind effect at free surface, the heat losses and the development of the double-diffusive convection in the lower and upper convective zones are considered. The governing equations of continuity, momentum, thermal energy and diffusion are solved using the finite volume method with SIMPLE algorithm. The validity of the numerical model developed in Fortran95 is achieved through the comparisons of the results computed with the available numerical and experimental results obtained by literature studies. Results show that the developed numerical model can predict transient behavior of the SGSPs with a good accuracy. As an application of this model, temperature, salt concentration, energy stored and storage efficiency variations of a proposed SGSP are analyzed under Mediterranean climate. The results show that the lower convective zone(LCZ) temperature increases from 15 °C to around 95 °C whereas the temperature of the upper convective zone(UCZ) varies sinusoidally depending on that of the ambient air. Furthermore, the salt concentration of the LCZ decreases from 250kg/m3 to around 248kg/m3 while that of the UCZ increases from50 kg/m3 to about 52kg/m3. Additionally, the thermal energy stored is around 135MJ with an efficiency of about 38% which confirms the capacity of the SGSP to store thermal energy as sensible heat.
{"title":"Transient behavior of a salinity gradient solar pond under Mediterranean climate","authors":"Yassmine Rghif, A. Sayer, Hameed B. Mahood","doi":"10.1115/1.4056788","DOIUrl":"https://doi.org/10.1115/1.4056788","url":null,"abstract":"\u0000 This paper aims to investigate the transient behavior of a salinity gradient solar pond(SGSP) under Mediterranean climate. For this propose, a 2D numerical model is developed in which the absorption of solar radiation by different layers of saline water, the wind effect at free surface, the heat losses and the development of the double-diffusive convection in the lower and upper convective zones are considered. The governing equations of continuity, momentum, thermal energy and diffusion are solved using the finite volume method with SIMPLE algorithm. The validity of the numerical model developed in Fortran95 is achieved through the comparisons of the results computed with the available numerical and experimental results obtained by literature studies. Results show that the developed numerical model can predict transient behavior of the SGSPs with a good accuracy. As an application of this model, temperature, salt concentration, energy stored and storage efficiency variations of a proposed SGSP are analyzed under Mediterranean climate. The results show that the lower convective zone(LCZ) temperature increases from 15 °C to around 95 °C whereas the temperature of the upper convective zone(UCZ) varies sinusoidally depending on that of the ambient air. Furthermore, the salt concentration of the LCZ decreases from 250kg/m3 to around 248kg/m3 while that of the UCZ increases from50 kg/m3 to about 52kg/m3. Additionally, the thermal energy stored is around 135MJ with an efficiency of about 38% which confirms the capacity of the SGSP to store thermal energy as sensible heat.","PeriodicalId":17124,"journal":{"name":"Journal of Solar Energy Engineering-transactions of The Asme","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45969002","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The interest in absorption chillers for air conditioning applications has increased recently due to the negligible electricity requirement. Especially in Turkey, where the potential of renewable energy sources such as solar energy is high, it is possible to achieve significant energy savings by utilizing absorption chillers. This study presents comprehensive energy and exergy analyses of a solar-driven single-effect absorption chiller with LiBr+LiCl/H2O (mass ratio 2:1) solution mixture. Thermodynamic optimization is carried out for the first time in this study to determine the optimum generator temperature using different absorber and condenser temperatures to maximize exergy efficiency of the absorption chiller. Also, generator temperature ranges for each absorber and condenser level are determined in this study so that the chiller using solution mixture can operate without crystallization. Coefficient of Performance, total exergy destruction rate and exergy efficiency of solar-driven absorption chiller for solar collector area of 194 m2 under a certain optimized operating condition are 0.402, 113.63 kW and 1.255%, respectively. Thanks to an alternative solution mixture compared to LiBr/H2O, the effective thermodynamic parameters can be improved and become more advantageous. The comparison results demonstrated that the thermodynamic performance of the system not only increased but also the thermal capacities and collector area decreased.
{"title":"Thermodynamic optimization of utilization of LiBr+LiCl/H2O solution mixture on a single-effect absorption chiller driven by solar energy","authors":"Cenker Aktemur, I. Öztürk","doi":"10.1115/1.4056738","DOIUrl":"https://doi.org/10.1115/1.4056738","url":null,"abstract":"\u0000 The interest in absorption chillers for air conditioning applications has increased recently due to the negligible electricity requirement. Especially in Turkey, where the potential of renewable energy sources such as solar energy is high, it is possible to achieve significant energy savings by utilizing absorption chillers. This study presents comprehensive energy and exergy analyses of a solar-driven single-effect absorption chiller with LiBr+LiCl/H2O (mass ratio 2:1) solution mixture. Thermodynamic optimization is carried out for the first time in this study to determine the optimum generator temperature using different absorber and condenser temperatures to maximize exergy efficiency of the absorption chiller. Also, generator temperature ranges for each absorber and condenser level are determined in this study so that the chiller using solution mixture can operate without crystallization. Coefficient of Performance, total exergy destruction rate and exergy efficiency of solar-driven absorption chiller for solar collector area of 194 m2 under a certain optimized operating condition are 0.402, 113.63 kW and 1.255%, respectively. Thanks to an alternative solution mixture compared to LiBr/H2O, the effective thermodynamic parameters can be improved and become more advantageous. The comparison results demonstrated that the thermodynamic performance of the system not only increased but also the thermal capacities and collector area decreased.","PeriodicalId":17124,"journal":{"name":"Journal of Solar Energy Engineering-transactions of The Asme","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41684824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Photovoltaic (PV) panels convert solar radiation into electrical energy in a clean and cost-effective way. PV panels are positioned against the Sun using fixed or solar tracking systems to generate electricity at maximum efficiency. Although solar tracking systems work with 30-40% higher efficiency than fixed solar systems, they do not attract commercial attention due to their high investment and maintenance costs. In this study, a single motor and dual-axis solar tracking system called asymmetric solar tracker (AST) was designed. The most significant innovation of AST is the adjustable asymmetrical stand that carries the PV panels. Thanks to its asymmetrical stand, AST does not need concrete or heavy metal construction to carry PV panels, as in traditional solar tracking systems. In addition, AST can track the Sun on the dual axis by moving on a single axis owing to its asymmetrical stand. These features make AST approximately as cost-effective as fixed solar systems and as efficient as dual-axis solar tracking systems. As an experimental study, an AST for two PV panels was fabricated and compared with a fixed solar system under different weather conditions. Arduino Uno microcontroller was employed to control AST and LDR sensors were used to track the instant position of the Sun. Experimental results reveal that, depending on the weather conditions, AST increases the daily electrical energy produced by PV panels between 25% and 38% compared to the fixed solar system.
{"title":"Single Motor and Dual Axis Solar Tracking System for Micro PV Power Plants","authors":"A. Karabiber, Yunus Güneş","doi":"10.1115/1.4056739","DOIUrl":"https://doi.org/10.1115/1.4056739","url":null,"abstract":"\u0000 Photovoltaic (PV) panels convert solar radiation into electrical energy in a clean and cost-effective way. PV panels are positioned against the Sun using fixed or solar tracking systems to generate electricity at maximum efficiency. Although solar tracking systems work with 30-40% higher efficiency than fixed solar systems, they do not attract commercial attention due to their high investment and maintenance costs. In this study, a single motor and dual-axis solar tracking system called asymmetric solar tracker (AST) was designed. The most significant innovation of AST is the adjustable asymmetrical stand that carries the PV panels. Thanks to its asymmetrical stand, AST does not need concrete or heavy metal construction to carry PV panels, as in traditional solar tracking systems. In addition, AST can track the Sun on the dual axis by moving on a single axis owing to its asymmetrical stand. These features make AST approximately as cost-effective as fixed solar systems and as efficient as dual-axis solar tracking systems. As an experimental study, an AST for two PV panels was fabricated and compared with a fixed solar system under different weather conditions. Arduino Uno microcontroller was employed to control AST and LDR sensors were used to track the instant position of the Sun. Experimental results reveal that, depending on the weather conditions, AST increases the daily electrical energy produced by PV panels between 25% and 38% compared to the fixed solar system.","PeriodicalId":17124,"journal":{"name":"Journal of Solar Energy Engineering-transactions of The Asme","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44709221","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Vijay Muniyandi, M. Saravanan, Ashok Kumar Balasubramanian
A partially shaded photovoltaic (PV) array's characteristic curve is convoluted due to disparity in irradiance levels between shaded and unshaded PV panels, resulting in power mismatch losses. This work presents a new hybrid approach combining the Magic Square (MS) array configuration and Differential Evolution based adaptive perturb and observe (DEAPO) MPPT methodology to overcome the abovementioned problem. The proposed hybrid methodology is implemented in two steps: first, repositioning the PV panels as per the MS configuration to decrease the power losses of partial shading. In MS configuration, the concentrated shadow on a single row or column can spread over to the entire PV array equally without any physical or electrical switching of PV panels. Second, the DEAPO MPPT method is developed to find the global peak power point on the PV characteristic curve. PID controller coefficients are optimized by DE to enhance the tracking speed and convergence of the adaptive P&O MPPT. The simulation study of this work has been implemented using PV arrays in MATLAB/SIMULINK environment and the real-time validation is done through a 5 kW PV array. The proficiency of the proposed hybrid approach is tested by creating various non-uniform and uniform shading patterns on the PV array. The simulation and experimental results prove that the proposed hybrid approach increases the power output by 19% and 20% higher than the existing Total Cross Tie (TCT) configuration under non-uniform and uniform shading cases respectively.
{"title":"Improving the Power Output of a Partially Shaded Photovoltaic Array through a Hybrid Magic Square Configuration with Differential Evolution based Adaptive P&O MPPT Method","authors":"Vijay Muniyandi, M. Saravanan, Ashok Kumar Balasubramanian","doi":"10.1115/1.4056621","DOIUrl":"https://doi.org/10.1115/1.4056621","url":null,"abstract":"\u0000 A partially shaded photovoltaic (PV) array's characteristic curve is convoluted due to disparity in irradiance levels between shaded and unshaded PV panels, resulting in power mismatch losses. This work presents a new hybrid approach combining the Magic Square (MS) array configuration and Differential Evolution based adaptive perturb and observe (DEAPO) MPPT methodology to overcome the abovementioned problem. The proposed hybrid methodology is implemented in two steps: first, repositioning the PV panels as per the MS configuration to decrease the power losses of partial shading. In MS configuration, the concentrated shadow on a single row or column can spread over to the entire PV array equally without any physical or electrical switching of PV panels. Second, the DEAPO MPPT method is developed to find the global peak power point on the PV characteristic curve. PID controller coefficients are optimized by DE to enhance the tracking speed and convergence of the adaptive P&O MPPT. The simulation study of this work has been implemented using PV arrays in MATLAB/SIMULINK environment and the real-time validation is done through a 5 kW PV array. The proficiency of the proposed hybrid approach is tested by creating various non-uniform and uniform shading patterns on the PV array. The simulation and experimental results prove that the proposed hybrid approach increases the power output by 19% and 20% higher than the existing Total Cross Tie (TCT) configuration under non-uniform and uniform shading cases respectively.","PeriodicalId":17124,"journal":{"name":"Journal of Solar Energy Engineering-transactions of The Asme","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47202036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper reports the computational results of fluid flow and thermal characteristics in isosceles trapezoidal solar air heater (SAH). By varying the base angle of the trapezoidal duct from 90° to 45°, six different models of solar air heater ducts are obtained, namely: a rectangular, four isosceles trapezoids and one triangular duct geometries. The absorber plate width and the duct heights are maintained constant for all the six models of SAH, i.e. 160 mm and 80 mm respectively. The SAH is subjected to a constant and uniform heat flux value of 1000 W/m2 and Reynolds numbers varied from 5,000 to 28,000. For this investigation, a three dimensional computational model has been developed and simulations are carried out by using a commercially available ANSYS fluent software. The numerical results are validated with the standard correlations & literature data and a suitable model has been identified for the turbulence closure. A detailed analysis of the Nusselt number and temperature distribution over the SAH, friction factor across the SAH duct is done. Empirical correlations for the estimation of heat transfer and friction factor have been developed as functions of the base angle of the duct and Reynolds number. An overall performance factor is adopted to get the combined effect of friction factor and Nusselt number with an intension to arrive at the optimum base angle of the SAH duct and optimum geometry is identified.
{"title":"Effect of base angle of an isosceles trapezoidal solar air heater duct on flow and thermal characteristics - A numerical investigation","authors":"Rambabu Dara, Pullarao Muvvala","doi":"10.1115/1.4056625","DOIUrl":"https://doi.org/10.1115/1.4056625","url":null,"abstract":"\u0000 This paper reports the computational results of fluid flow and thermal characteristics in isosceles trapezoidal solar air heater (SAH). By varying the base angle of the trapezoidal duct from 90° to 45°, six different models of solar air heater ducts are obtained, namely: a rectangular, four isosceles trapezoids and one triangular duct geometries. The absorber plate width and the duct heights are maintained constant for all the six models of SAH, i.e. 160 mm and 80 mm respectively. The SAH is subjected to a constant and uniform heat flux value of 1000 W/m2 and Reynolds numbers varied from 5,000 to 28,000. For this investigation, a three dimensional computational model has been developed and simulations are carried out by using a commercially available ANSYS fluent software. The numerical results are validated with the standard correlations & literature data and a suitable model has been identified for the turbulence closure. A detailed analysis of the Nusselt number and temperature distribution over the SAH, friction factor across the SAH duct is done. Empirical correlations for the estimation of heat transfer and friction factor have been developed as functions of the base angle of the duct and Reynolds number. An overall performance factor is adopted to get the combined effect of friction factor and Nusselt number with an intension to arrive at the optimum base angle of the SAH duct and optimum geometry is identified.","PeriodicalId":17124,"journal":{"name":"Journal of Solar Energy Engineering-transactions of The Asme","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44174140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The solar flux incident on a volumetric receiver is inherently unsteady, resulting in high thermal stresses, fatigue failures and reduced component life. The knowledge of transient response characteristics of a porous volumetric receiver used in concentrating solar technologies is cardinal for its reliable and safe working. The dynamic controlling of the solar-to-thermal conversion process is also possible with the prior prediction of the output variations. The present study aims to investigate the transient behaviour of a porous volumetric receiver subjected to flux variations approximations occurring in real working scenarios with the help of a coupled transient model. The solid and fluid temperature fields, output fluid temperature and pressure drop variations are determined for transient flux conditions during start-up, shut-down, clear sky, and cloud passage. The results are used to analyze the thermal response of the receiver during various operating conditions. In addition, the effects of structural parameters of the porous absorber are also investigated. The results indicate that the receiver transient performance is comparatively more affected by the variation in porosity than in pore size for all conditions. Smaller porosities and pore sizes show slower thermal response to transient fluctuations and less temperature changes during cloud passage. Conversely, higher values help in the faster restoration of the steady-state output conditions without dynamic control.
{"title":"Dynamic Performance Characteristics of a Porous Volumetric Solar Receiver Under Transient Flux Conditions","authors":"Sonika Sharma, P. Talukdar","doi":"10.1115/1.4056622","DOIUrl":"https://doi.org/10.1115/1.4056622","url":null,"abstract":"\u0000 The solar flux incident on a volumetric receiver is inherently unsteady, resulting in high thermal stresses, fatigue failures and reduced component life. The knowledge of transient response characteristics of a porous volumetric receiver used in concentrating solar technologies is cardinal for its reliable and safe working. The dynamic controlling of the solar-to-thermal conversion process is also possible with the prior prediction of the output variations. The present study aims to investigate the transient behaviour of a porous volumetric receiver subjected to flux variations approximations occurring in real working scenarios with the help of a coupled transient model. The solid and fluid temperature fields, output fluid temperature and pressure drop variations are determined for transient flux conditions during start-up, shut-down, clear sky, and cloud passage. The results are used to analyze the thermal response of the receiver during various operating conditions. In addition, the effects of structural parameters of the porous absorber are also investigated. The results indicate that the receiver transient performance is comparatively more affected by the variation in porosity than in pore size for all conditions. Smaller porosities and pore sizes show slower thermal response to transient fluctuations and less temperature changes during cloud passage. Conversely, higher values help in the faster restoration of the steady-state output conditions without dynamic control.","PeriodicalId":17124,"journal":{"name":"Journal of Solar Energy Engineering-transactions of The Asme","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48552830","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Electricity and gas-based heat treatment of metal is an energy-intensive process. To mitigate the use of such high-grade energy the concept of an open volumetric air receiver-based solar convective furnace (SCF) system is developed for the heat treatment of metal. This system includes an in-situ waste heat recovery mechanism. This paper presents a Joule heating-based, controlled, experimental assessment of a laboratory-scale, retrofitted, SCF system for generating benchmark data. The reported measurements illustrate the heat transfer for (a) the charging and discharging process of thermal energy storage and (b) the two-stage heat treatment of metal with an in-situ heat recovery process. The overall system efficiency, including heat recovery, heat storage, and heat transfer, is found to be 24%. Thus, the SCF system can serve as a viable alternative to an electrical energy-based heat treatment furnace.
{"title":"Simulated Experimental Assessment of a Laboratory-Scale Solar Convective Furnace System","authors":"V. Kumar, L. Chandra, S. Mukhopadhyay, R. Shekhar","doi":"10.1115/1.4056623","DOIUrl":"https://doi.org/10.1115/1.4056623","url":null,"abstract":"\u0000 Electricity and gas-based heat treatment of metal is an energy-intensive process. To mitigate the use of such high-grade energy the concept of an open volumetric air receiver-based solar convective furnace (SCF) system is developed for the heat treatment of metal. This system includes an in-situ waste heat recovery mechanism. This paper presents a Joule heating-based, controlled, experimental assessment of a laboratory-scale, retrofitted, SCF system for generating benchmark data. The reported measurements illustrate the heat transfer for (a) the charging and discharging process of thermal energy storage and (b) the two-stage heat treatment of metal with an in-situ heat recovery process. The overall system efficiency, including heat recovery, heat storage, and heat transfer, is found to be 24%. Thus, the SCF system can serve as a viable alternative to an electrical energy-based heat treatment furnace.","PeriodicalId":17124,"journal":{"name":"Journal of Solar Energy Engineering-transactions of The Asme","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48934578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Methida Siritan, K. Vafai, N. Kammuang-lue, P. Terdtoon, P. Sakulchangsatjatai
In this work, an innovative design for a solar water heating system using a flat-shaped heat pipe as a heat transfer device is presented to pave the way for a substantial increase in the thermal performance of these systems. An analytical study is utilized to investigate the thermal performance of the solar water heating system. The analytical results for the flat-shaped heat pipe system are compared with the results of the evacuated tube solar water heating system with a U-tube, thermosyphon, and closed-loop pulsating heat pipe. It is found that the water temperature difference between the inlet and outlet of the flat-shaped heat pipe system is substantially higher than the U-tube, thermosyphon, and closed-loop pulsating heat pipe system by as much as 31.4, 22.5, and 18.5 °C, respectively at a nominal 0.6 L/min mass flow rate. Furthermore, utilizing the flat-shaped heat pipe in the solar water heating system optimizes the thermal conductivity of the solar setup due to a reduction in the condenser section length. These reductions also lead to a large reduction in the weight and cost of the system.
{"title":"An Innovative Design for a Solar Water Heating System Utilizing a Flat-Shaped Heat Pipe","authors":"Methida Siritan, K. Vafai, N. Kammuang-lue, P. Terdtoon, P. Sakulchangsatjatai","doi":"10.1115/1.4056624","DOIUrl":"https://doi.org/10.1115/1.4056624","url":null,"abstract":"\u0000 In this work, an innovative design for a solar water heating system using a flat-shaped heat pipe as a heat transfer device is presented to pave the way for a substantial increase in the thermal performance of these systems. An analytical study is utilized to investigate the thermal performance of the solar water heating system. The analytical results for the flat-shaped heat pipe system are compared with the results of the evacuated tube solar water heating system with a U-tube, thermosyphon, and closed-loop pulsating heat pipe. It is found that the water temperature difference between the inlet and outlet of the flat-shaped heat pipe system is substantially higher than the U-tube, thermosyphon, and closed-loop pulsating heat pipe system by as much as 31.4, 22.5, and 18.5 °C, respectively at a nominal 0.6 L/min mass flow rate. Furthermore, utilizing the flat-shaped heat pipe in the solar water heating system optimizes the thermal conductivity of the solar setup due to a reduction in the condenser section length. These reductions also lead to a large reduction in the weight and cost of the system.","PeriodicalId":17124,"journal":{"name":"Journal of Solar Energy Engineering-transactions of The Asme","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42862147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We present a literature review of experimental studies aiming to characterize soiling and its effects on the generation performance of photovoltaic (PV) systems. The methodology is based on a Systematic Review of the Literature (SRL) through the elaboration and implementation of a conduction protocol, with selection criteria, search strategies and extraction and summarization procedures. In the search and identification, 3,018 Primary Studies (PSs) are initially obtained, with 151 PSs being admitted for extraction and summarization. The bibliometric analysis identifies the annual distribution of publications, main researchers, means of scientific dissemination and most used terms as keywords. The short-circuit current (Isc) is usually the parameter most affected by dirt; considering other parameters, different behaviors are identified, depending on the PV technology. The chemical elements most reported are Ca, Si, Al, O, Fe and Mg; the main mineral compounds are quartz, calcite, hematite, gypsum, and orthoclase.
{"title":"Analysis of the characteristics and effects of soiling natural accumulation on 2 photovoltaic systems: a systematic review of the literature","authors":"J. Souza, P. Carvalho, G. Barroso","doi":"10.1115/1.4056453","DOIUrl":"https://doi.org/10.1115/1.4056453","url":null,"abstract":"\u0000 We present a literature review of experimental studies aiming to characterize soiling and its effects on the generation performance of photovoltaic (PV) systems. The methodology is based on a Systematic Review of the Literature (SRL) through the elaboration and implementation of a conduction protocol, with selection criteria, search strategies and extraction and summarization procedures. In the search and identification, 3,018 Primary Studies (PSs) are initially obtained, with 151 PSs being admitted for extraction and summarization. The bibliometric analysis identifies the annual distribution of publications, main researchers, means of scientific dissemination and most used terms as keywords. The short-circuit current (Isc) is usually the parameter most affected by dirt; considering other parameters, different behaviors are identified, depending on the PV technology. The chemical elements most reported are Ca, Si, Al, O, Fe and Mg; the main mineral compounds are quartz, calcite, hematite, gypsum, and orthoclase.","PeriodicalId":17124,"journal":{"name":"Journal of Solar Energy Engineering-transactions of The Asme","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2022-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49619496","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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