For a water coil where both fluids are unmixed and flow is not pure counterflow, the “effective” mean temperature difference is usually computed with which form?
Choices
- (A) Dry-bulb of room only
- (B) Simple arithmetic average in all cases
- (C) Log-mean of dry-bulb and humidity
- (D) LMTD with correction F for crossflow/mixed, or use ε-NTU in detailed models
Correct answer: (D)
LMTD with correction F for crossflow/mixed, or use ε-NTU in detailed models
Explanation
Heat transfer texts: LMTD with F, or ε-NTU; ASHRAE chapters reference coil modeling.