The increasing global demand for sustainable energy has driven advancements in solar thermal technologies,particularly in solar parabolic dish collectors(PDCs).The performance of a PDC depends on the absorption of sol...The increasing global demand for sustainable energy has driven advancements in solar thermal technologies,particularly in solar parabolic dish collectors(PDCs).The performance of a PDC depends on the absorption of solar irradiance and heat loss through the receiver.Furthermore,to address the problems of solar intermittency and lack of irradiance after sunset requires thermal energy storage.Consequently,an appropriate design of the receiver is necessary for maximizing the performance of the PDC.This study investigated the incorporation of phase change materials(PCMs)into conical cavity receivers to enhance the thermal energy storage and efficiency of PDCs.To examine this,a comparative experimental analysis was conducted on a PCM-filled conical receiver and a conventional cylindrical receiver under identical operating conditions.The methodology involved measuring key performance metrics,such as the thermal efficiency,exergy efficiency,Nusselt number,and heat transfer coefficients,across varying flow rates of the heat transfer fluid.The results demonstrated that the PCM-integrated conical receiver achieved a 42%increase in the thermal efficiency and a 31%improvement in the exergy efficiency compared to the cylindrical design.The capacity of the conical receiver for intercepting solar radiation and PCM integration contributed to superior heat transfer performance,particularly at higher flow rates,as evidenced by the elevated Nusselt numbers and convection heat transfer coefficients.These findings highlight the potential of PCM-integrated conical receivers for mitigating the challenges of intermittent solar irradiance and enhancing the reliability and sustainability of solar thermal systems.展开更多
文摘The increasing global demand for sustainable energy has driven advancements in solar thermal technologies,particularly in solar parabolic dish collectors(PDCs).The performance of a PDC depends on the absorption of solar irradiance and heat loss through the receiver.Furthermore,to address the problems of solar intermittency and lack of irradiance after sunset requires thermal energy storage.Consequently,an appropriate design of the receiver is necessary for maximizing the performance of the PDC.This study investigated the incorporation of phase change materials(PCMs)into conical cavity receivers to enhance the thermal energy storage and efficiency of PDCs.To examine this,a comparative experimental analysis was conducted on a PCM-filled conical receiver and a conventional cylindrical receiver under identical operating conditions.The methodology involved measuring key performance metrics,such as the thermal efficiency,exergy efficiency,Nusselt number,and heat transfer coefficients,across varying flow rates of the heat transfer fluid.The results demonstrated that the PCM-integrated conical receiver achieved a 42%increase in the thermal efficiency and a 31%improvement in the exergy efficiency compared to the cylindrical design.The capacity of the conical receiver for intercepting solar radiation and PCM integration contributed to superior heat transfer performance,particularly at higher flow rates,as evidenced by the elevated Nusselt numbers and convection heat transfer coefficients.These findings highlight the potential of PCM-integrated conical receivers for mitigating the challenges of intermittent solar irradiance and enhancing the reliability and sustainability of solar thermal systems.
