Analytical analysis of the thermal performance of building walls based on the thermal-electric analogy method
Dynamic thermal performance analysis of building wall is of great importance in analysing building energy consumption.However,conventional methods are usually complex for engineering applications and their physical mechanisms are not so clear.In order to simplify the analytical process with clear physical mechanism and investigate the energy transferred in the dynamic heat transfer process from both quality and quantity prospective,a new analysis method based on thermal-electric analogy was proposed in this paper.The thermal network model of dynamic heat transfer process of external wall was built based on thermal-electric analogy method.Several novel parameters such as thermal impedance and heat transfer dispassion were proposed,which can effectively simplify the analytical process and offer some novel insights.The results showed:(1)the propoased new parameter-thermal impedance can simutaneously reflect the co-resistant effect of thermal resistance and thermal capacitance.It will decrease with larger thermal conductivity and thermal capacitance;(2)there were three kinds of heat transfer dispassion in the dynamic heat transfer process.The part caused by thermal resistance was irreversible,and the part caused by thermal capacitance was reversible;(3)the extreme of heat transfer dispassion in the Thevenins equivalent circuit really corresponded to the extreme of heat flux transferred in one cycle.However the real heat transfer dispassion of all nodes didnt.The proposed novel concept and method can be used to build equivalent thermal network in built environment,which can provide a much simplified but more effective method with clear physical mechanism for engineering applications.
Thermal-electrical Analogy Dynamic Heat Transfer Process Thermal Impedance Heat Transfer Dispassion
Rui Cheng Xin Wang Yinping Zhang
Department of Building Science,Tsinghua University,Beijing,China
国际会议
桂林
英文
1-10
2013-07-16（万方平台首次上网日期，不代表论文的发表时间）