engineering recuitment Gujarat Metro JE Mock Test 2023 Heat Transfer Radiation Heat Exchange Between Non-Black Bodies
For infinite parallel planes with emissivities ε1 and ε2, the interchange factor for radiation from surface 1 to surface 2 is given by
1
\(\frac{{{\varepsilon _1}{\varepsilon _2}}}{{{\varepsilon _1} + {\varepsilon _2} - {\varepsilon _1}{\varepsilon _2}}}\)
2
\(\frac{1}{{{\varepsilon _1}}} + \frac{1}{{{\varepsilon _2}}}\)
3
ε1 + ε2
4
ε1 ε2