Cold Chain Parcel Thermal Budget Calculator

Calculate whether a cold chain parcel’s insulation and coolant capacity can withstand ambient conditions for the required hold time without exceeding the product temperature limit.

Overall heat transfer coefficient times surface area for the parcel.
Temperature difference between ambient and product limit. Use a positive value.
Transit or dwell time the package must maintain temperature.
Latent plus sensible energy the coolant can absorb. Defaults to 200 Wh when blank.

Qualification aid only. Validate with instrumented parcel testing that matches your shipping lane profiles and regulatory requirements.

Examples

  • UA 1.8 W/K, 25°C delta, 24 hours, 420 Wh coolant ⇒ Heat gain 1,080.00 Wh, coolant shortfall 660.00 Wh (beyond limit).
  • UA 0.9 W/K, 18°C delta, 10 hours, coolant left blank (defaults 200 Wh) ⇒ Heat gain 162.00 Wh, margin +38.00 Wh within limit.

FAQ

How do I estimate UA?

Use chamber test data or approximate from thermal conductivity of panels and surface area. For quick estimates, divide measured steady-state heat gain (W) by the applied temperature difference (K).

Does deltaT change during shipping?

Yes, but using the worst-case sustained ambient temperature keeps the calculation conservative. Re-run with multiple segments if exposure changes.

Can I include product thermal mass?

This calculator focuses on insulation and coolant. If the product acts as thermal ballast, increase the coolant capacity value to reflect the additional energy absorption.

Additional Information

  • Result unit: watt-hours of heat load versus available coolant energy.
  • Coolant defaults to 200 Wh when unspecified; adjust upward when using multiple frozen gel packs or dry ice equivalents.
  • UA should reflect packaging as packed, including payload conduction paths and any voids.

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