Afurnace wall is to be built of 20-cm firebrick and building (structural) brick of same thickness. the thermal conductivities of fire brick and building brick are 1.6 and 0.7 w/m. k , respectively. the inner surface of the firebrick is at 980 °c, the outer surface of the structural brick is at 30 °c. the heat flux and the temperature of the brick interface are..

q=2313.04

T=690.86°C

Explanation:

Given that

Thickness t= 20 cm

Thermal conductivity of firebrick= 1.6 W/m.K

Thermal conductivity of structural brick= 0.7 W/m.K

Inner temperature of firebrick=980°C

Outer temperature of structural brick =30°C

We know that thermal resistance

These are connect in series

Heat transfer

So heat flux

q=2313.04

Lets temperature between interface is T

Now by equating heat in both bricks

So T=690.86°C