Net heat exchange between two black bodies - Heat Transfer
Q. Assume that two black bodies of areas A1 and A2 are placed as shown in figure. dA1 and dA2 are the small area elements of the black bodies. The distance between them is r and the angles made by the normals of the surfaces with the joining line are Φ1 and Φ2 respectively. What is the formula for net heat exchange (Q12)net between A1and A2? Given that
A1F12 = A2 F21
for the shape factors F12 and F21- Published on 11 Aug 15a. (Q12)net = A1F12 σ (T14 – T24)
b. (Q12)net = A1F12 A2 F21 σ (T14 – T24)
c. (Q12)net = F12 F21 σ (T14 – T24)
d. none of the above
ANSWER: (Q12)net = A1F12 σ (T14 – T24)
