Question

For an infiltration rate of 1.32 air changes per hour (ACH), determine sensible, latent, and total infiltration heat load of a building at sea level, in kW, that is 20 m long, 13 m wide, and 3 m high when the outdoor air is at 32°C and 35 percent relative humidity. The building is maintained at 24°C and 55 percent relative humidity at all times. The gas constant and the specific heat of air are R = 0.287 kPa·m³/kg·K and c_p = 1.005 kJ/kg·°C, respectively. Use data from the tables.

The sensible infiltration heat load of the room is  kW.

The latent infiltration heat load of the room is  kW.

The total infiltration heat load of the room is  kW.

Answer 1

Given: building temperature

relative humidity

ambient temperature

relative humidity

From the psychrometric chart we determine the humidity ratios

We will calculate the volume

From ideal gas equation we will determine the density of outside air

mass flow rate of air entering the room given ACH = 1.32

enthalpy at room temperature Tr ==>

sensible

latent  

Total heat transfer