Derive an equation for the net rate of radiant heat transfer from surface 1 in the system shown in the accompanying sketch. Assume that each surface is at a uniform temperature and that the geometrical shape factor F1–2 is 0.1.
IVEN
• The system shown above
FIND
• An expression for the net rate of radiant heat transfer from surface 1 (q1) ASSUMPTIONS
• Steady state
• A1 and A2 are gray, A0 is black
• Each surface is at a uniform temperature
• The shape factor F12 = 0.1
PROPERTIES AND CONSTANTS
he Stephan-Boltzmann constant (?) = 5.67× 10–8 W/(m2 K4)
All of the shape factors for the problem can be expressed in terms of F12 using
the fact that all shape factors from a given surface must sum to unity.
Also
The net rate of heat transfer from surface 1 is
Where the radiosity (J1) and the irradiation (G1) can be calculated
Substituting [2] and [3] into this Equation
where
You might also like to view...
A breadcrumb trail is an example of local navigation.
Answer the following statement true (T) or false (F)
Comparing the near and far sides of the Moon, we find that the far side ________.
A. has a much lower temperature than the near side B. has as many maria as the near side C. has regolith composed mostly of basalt D. is more heavily cratered than the near side E. All of these choices are correct.
Venus is usually either the "evening star" or the "morning star" because
A) its orbit around the sun is inside Earth's orbit. B) its orbit around the sun is outside Earth's orbit. C) it is usually on the opposite side of the sun, relative to Earth. D) it is usually on the same side of the sun, relative to Earth. E) Actually, the evening or morning star is usually Mars, not Venus.
How is the Schwartzschild radius calculated from the mass of a star?
What will be an ideal response?