Thermal imb alance in hot box apparatus and in-situ measurements

摘要

Starting from the measurement principle for the etermination of thermal resistance of a building element in the laboratory (guarded hot box method) and in-situ, possible testing errors are considered, in particular those due to temperature non-uniformity and imbalance between the metering and guard section. Almost all in-situ measurements are carried out in non-steady-state conditions, nevertheless imbalance problems are similar to those of such steady-state test methods as the guarded hot box.