Moisture and frost in fiberglass insulation : second report / by Robert W. Besant and Yong-Xin Tao.

This report presents an experimental procedure of measuring the heat of desorption, followed by an analysis of the effect of thermal hysteresis on the transient heat and mass diffusion processes in fiberglass insulation. This analysis incorporates the experimental results of the heats of sorption. An experimental method that is used to study air infiltration/exfiltration effects in fiberglass insulation is then described, and the experimental results for temperature and moisture distributions under exfiltration conditions are presented. Finally, a transient, one-dimensional model for simultaneous heat and mass transfer with both phase changes and airflow (exfiltration effect) is presented, and the predictions are discussed and compared with the measured data. Although this study has quantified the significance of each of several physical phenomena in fiberglass insulation and the size of errors that could result from the use of overly simplified models, much more work is required to investigate the behavior of fiberglass insulation under typical ranges of operating conditions.