The dynamic heat transfer of building surfaces has thermal conduction, convection and radiation at the same time. It is the basis of building thermal environment simulation, air conditioning load calculation, building energy analysis and air conditioning system conservation operation. Under cyclic heat flow, the convection and radiation separating method was used to calculate the radiation heat and convection heat of building surfaces, and dynamic characteristics of convection heat and radiation heat on building surfaces was provided in this paper. For the dynamic heat transfer of building surfaces under cyclic heat flow, three indexes of peak error, mean error and average relative error were used to analyze dynamic heat transfer. The temperature distribution and dynamic heat transfer of convection heat and radiation heat of building surfaces were studied systematically. The separating cooling load and the room cooling load were basically consistent with each other, the convection and radiation separating method was reliable and available. The peak value of convection heat corresponded to the foot value of the radiation heat, and the relative error of them was 1.9%-2.2%. The dynamic characteristics of radiation heat and convection heat had important reference for the study of dynamic heat transfer of building surfaces under cyclic heat flow.
