Delta T (ΔT) is a fundamental concept in refrigeration and HVAC systems. It represents the temperature difference between two points in a system, being essential for equipment sizing and operation.
Basic Formula
ΔT = T inlet - T outlet
- Where:
- T inlet = Temperature of water entering the equipment
- T outlet = Temperature of water leaving the equipment
Typical ΔT Values
| Application | Typical ΔT |
|---|---|
| Chilled water systems | 5-6°C |
| Industrial processes | 3-10°C |
| Comfort cooling | 5-7°C |
| Data centers | 8-12°C |
| High load processes | 10-15°C |
Importance of ΔT
1. Equipment Sizing Cooling capacity is directly related to ΔT:
Q = m × Cp × ΔT
- Where:
- Q = Heat removed (kW)
- m = Mass flow rate (kg/s)
- Cp = Specific heat (4.186 kJ/kg·°C for water)
- ΔT = Temperature difference (°C)