PASSIVE EDGE / PCM

Cold-chain transport PCM sizing

Estimate enclosure and door or lid opening loads, then compare PCM mass with and without openings. Send us your conditions for a detailed engineering review.

Reference scenario (loads example values)

Refrigerated vehicleInsulated box

Presets are examples, not rated equipment data. The default assumes one air-volume exchange per minute while open. Door orientation, wind, loading and handling affect actual exchange; adjust using measurements.

1. Transport and insulation

External surface area m²Overall U-value W/(m²·K)Transport / hold time hAmbient temperature °CInternal target temperature °CPCM latent heat kJ/kg

2. Door / lid openings

Number of openings Duration per opening sExchangeable air volume m³Additional time left open min

Use internal volume minus cargo volume for exchangeable air. Enter repeated openings and their duration. Add separate loading time only if it is not already counted.

3. Adjustable assumptions

Effective air changes while open min⁻¹Ambient relative humidity %Internal relative humidity %Atmospheric pressure kPaSafety factor

Request detailed results by email

Calculate first, then create an editable email draft with the current inputs and results. Send it to hi@passive-edge.cn for project review and detailed results.

Method and scope

Transmission = U × area × temperature difference × time. Opening load = exchanged air volume × dry-air density × cooling and dehumidification enthalpy difference. Open time = count × duration + additional open time. PCM mass = total heat × safety factor / latent heat.

ASHRAE · Heat-load method reference · cold-chain-20260922-v1