LO-2287 (RP 102) -- Application of System Identification Techniques to the Determination of Thermal Response Factors from Experimental Data

The demands placed upon designers of heating and cooling equipment for buildings in recent years have resulted in a new method of analyzing transient heat flow through walls -the Thermal Response Factor method. This makes possible to analyze the heat flux through a wall with arbitrary and time varying outside conditions on an hour-by-hour basis. For simple homogeneous isotropic slabs, and composite walls made of these slabs, the thermal response factors can be analytically calculated. However, many commonly used building wall sections are neither homogeneous nor isotropic, and the appropriate analytical procedures for determining response factors for such walls have not been determined. Accordingly, RP-I02 was established to develop an experimental procedure for measuring the heat flux through common bUilding wall sections under transient conditions, and, if possible, determine their response factors. Only the first pliase of the research project has been completed; but the experimental procedure found to work satisfactorily is presented in this paper although it does not represent the final report.