Two plates spaced 150 mm apart are maintained at 1000°C and 70°C. The heat transfer will take place mainly by
The radiation heat exchange between parallel plates is given by
Q1 = σ(T14 − T24)
Q = Heat transfer per unit time
T = Temperature
The total radiant heat energy emitted by a surface is proportional to the fourth power of its absolute temperature (the Stefan–Boltzmann law).
At high temperatures, radiation transfer will be high due to 4th power of temperature. Hence the heat transfer will take place mainly by radiation