Time to cool a loaded cold room from ambient to set-point, given refrigeration plant duty and thermal load.
Formula
$$ t = \frac{m \cdot c_p \cdot \Delta T}{(\dot Q_\text{plant} - \dot Q_\text{leak}) \cdot 3600} $$
Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| $m$ | Goods mass | kg | cargo manifest |
| $c_p$ | Specific heat | kJ/(kg·K) | cargo property |
| $ΔT$ | Temperature drop | K | set-point vs ambient |
| $\dot Q_\text{plant}$ | Plant cooling duty | kW | nameplate |
| $\dot Q_\text{leak}$ | Structural heat leak | kW | insulation U·A·ΔT |
Sources
- ASHRAE Handbook - Refrigeration.