Study on dynamic thermal control performance of positive temperature coefficient (PTC) material based on a novel heat transfer model considering internal heat transfer

Abstract

Positive temperature coefficient (PTC) material is widely used in thermal control due to its unique characteristics. In this paper, a novel heat transfer model of PTC material is proposed with consideration given to the internal heat transfer characteristics of the model which was ignored in the previous model, and it is validated by conducting experiment. Based on this novel heat transfer model, the effects exerted by thermal conductivity, heat capacity and thermal contact resistance on the thermal control of PTC material that have never been studied in previous work are investigated. In this paper, the PTC material with large heat capacity will extend the equilibrium time of the controlled device significantly. Besides, the dynamic thermal control performance of PTC material is verified by carrying out simulation. Herein, thermal control of PTC material under three different ambient temperature conditions is studied. As indicated by the results, PTC material has better thermal control performance under variable ambient temperatures. When the ambient temperature varies periodically with 5 °C amplitude and for a period of more than 300 s, the temperature of controlled device barely changes.