Wall-response factors to estimate the conduction heat gains with time-varying thermal coefficients

Abstract

A simple methodology for solving time-varying problems of transient heat flow through building envelopes is presented. In forming a typical model to evaluate the conduction heat gains, a sol-air heat instead of the sol-air temperature is defined and two related thermal-response factors are introduced. To deal with the time-dependent system properties, the response factors are normalized by their mean values of static gain, and the actual values of static gain are thus shifted to the thermal inputs. This procedure allows us to estimate the building thermal loads of a linear dynamic model with built-in, time-varying heat-transfer coefficients.