PCM Packed-Bed Thermal Storage: Thermocline Front

This simulator models a packed bed of encapsulated phase-change-material (PCM) spheres used as a thermal battery — the same design principle behind solar-thermal and district-heating storage tanks. Hot or cold heat-transfer fluid is pumped through the gaps between capsules; each capsule exchanges heat with the fluid layer by layer, following the Schumann two-phase packed-bed model, while its own temperature evolves through an effective-heat-capacity latent-heat law that captures the melting or freezing plateau around the PCM's transition temperature. Switch between charging (hot fluid melts the bed) and discharging (cold fluid freezes it back), choose a paraffin, salt-hydrate or fatty-acid PCM with its own melting point and latent heat, and watch a real thermocline — the moving boundary between charged and uncharged capsules — sweep down the column while stored-energy and melt-fraction readouts track the bed's state of charge.