Dynamic Characterization of Phase Change Materials Under Harmonic Heating

Cooling for time-varying thermal loads is of significant interest to the thermal management community, especially for applications in electronics packaging. For these applications, phase change materials (PCMs) have been identified as highly desirable candidate materials due to their high latent heat being a valuable aspect for managing transient thermal loads. However, the thermal response of these materials to time-varying loads leaves much room for exploration to ensure efficient utilization. In this study we develop a novel transient thermal measurement technique, and experimentally investigate the response of a PCM slab subjected to harmonic heating and convective cooling on opposing boundaries. An experimental rig is described which records temperature at the heated and cooled boundaries of a slab under investigation. Experimental observations provide insight into the role a phase change plays in damping the temperature of a heated surface, while also allowing a means of probing the fundamental thermal properties of the material under test. The result of this work is a characterization of PCM response to harmonic thermal loads and a contribution to the current understanding on how these materials should be applied for thermal management of non-steady heat sources. Furthermore, the contributions to our understanding of PCMs within this work can provide key insight for future design of thermal management systems and characterization methodologies.