Subtopic: Sensible heating process on psychrometric chart
Question Statement:
During a pure sensible heating process of moist air from State A to State B across a grain dryer heating coil (as depicted in the psychrometric chart), which of the following psychrometric changes occur?
Options:
(A) Humidity ratio (specific humidity) remains constant
(B) Dew point temperature remains constant
(C) Relative humidity decreases
(D) Enthalpy and dry bulb temperature increase
Answer Key:
A, B, C, D
Step-by-Step Solution & Explanation
During sensible heating, no moisture is added or removed, so humidity ratio and dew point temperature remain constant. As dry bulb temperature increases, saturation vapor pressure rises, causing relative humidity to drop and enthalpy to rise.