Consider steady heat transfer through the wall of a room in winter. The convection heat transfer coefficient at the outer surface of the wall is three times that of the inner surface as a result of the winds. Hence, at the inner surface, the temperature will be closer to the surrounding air temperature. Explain.

The heat transfer which is in steady state, the heat transfer rate to the wall is equal to the wall.

Explanation:

The convection transfer of heat to the wall is

         

Here, is the temperature of solid surface, is the temperature of moving fluid stream which is adjacent of solid surface, h is the heat transfer coefficient.The coefficient of convection heat transfers outer surface contains 3 times to the inner surface which experience smaller drop of temperature for 3 times that compares to inner surface.Hence, the temperatures outer surface get close to the surroundings of air temperature.