MO-2324 (RP-94) -- Summary Review of "Experimental Determination of Thermal Response Factors"

Summary by subcommittee of TC 4.4, "Insulation and Moisture Barriers" based on reports submitted by Professor Herbert B. Nottage, P.E., University of California, Los Angeles, CA.

The use of thermal response factors to calculate transient heat flow in building walls, floors, and roofs has been proposed for use in computerized load calculation procedures (1, 2, 3, and 4). The determination of these factors by theoretical calculation can and has been made for uniform isotropic materials where heat transfer can be assumed to be entirely one-dimensional (5, 6, and 7). However, many typical building sections contain materials having variable thermophysical properties, and in addition, the heat conduction that occurs is in many cases, multi-dimensional. Experimental determination of the response factors for these situations has been recommended (8).

A laboratory test apparatus has been built at UCLA to meet the requirements of the above mentioned need. A goal has also been established to determine the value of response factors to an accuracy within +/- 1 percent. In addition to serving as a research tool, it is hoped that the testing program will have large educational benefits for the students of Mechanical Engineering. The system is presently operational, and plans are underway to expand its capability to a fully automated system, including on-line calculation of the response factors.