Question 2 [4 points]
A small room with 5 m \times 4 m \times 3 m (height) is fitted with 2 tonnes of refrigeration (TR) system.
The room experiences a sensible and latent heat gain of 5 kW from the outside through radiation
and convection. The room should also gain 1 kW through occupants and 1 kW through equipment
and machines like refrigerators, microwaves, etc. The outdoor conditions are 45°C and 50% RH
and the inside desired conditions are 25°C and 50% RH. Ignore ventilation and infiltration.
Now, the 2 TR refrigeration system breaks down, and a 1 TR system accidently replaces it. What
will happen to the inside air temperature when you start from 25°C and turn on the 1 TR AC with
the original cooling loads present? Qualitatively show through the temperature profile. (1)
Will the room temperature ever reach a steady state? (1)
If so, can you find the approximate time when it will reach that steady state? (2)
(Hint: Energy balance)
