Exercise -2

In a 90 cm square flue, hot flue gas is flowing at the volumetric flow rate of . The inside surface temperature of the flue is  cooler than the hot gas temperature. Calculate the rate of heat flow from hot gas to the wall/m length when

1. Hot gas in dry air and at  
2. Hot gas in moist air at  and contains  moisture  
3. Hot gas is flue gas at   and whose composition is and

Data:   of air  

Kair