Paraffin PCM Thermal Buffer

n-Eicosane Paraffin PCM in Aluminum Cells

A paraffin phase change material thermal buffer is a passive heat-storage device comprising n-eicosane or n-octadecane wax sealed within an aluminum honeycomb matrix with internal fins. Designed to absorb transient thermal spikes from electronics duty cycles and equipment startup, the buffer exploits a latent heat capacity of 240 kJ/kg, with n-eicosane melting at approximately 37 °C and n-octadecane at 28 °C. In the lunar vacuum—where convective cooling is impossible and external temperatures swing across 300 K over 14-day cycles—the aluminum structure rapidly conducts excess equipment heat into the paraffin, buffering internal operating temperatures with zero electrical power consumption.

Paraffin (n-eicosane, n-octadecane) PCM thermal buffers in aluminum cells absorbing transient heat loads (electronics duty cycles, equipment startup).