What is the heat flux (in W/m^2) from the surface of the sun (assuming black body behavior)if the surface temperature is 5527 C?
Question 10 options:
64.2 E6 |
|
1.49 E5 |
|
7.53 E6 |
|
48.2 E6 |
|
1.07 E7 |
|
52.9 E6 |
|
cannot be determined with the information provided |
What is the heat flux (in W/m^2) from the surface of the sun (assuming black body...
3. The sun can be approximated as a spherical black body with a surface temperature of 5762 K. The irradiation from the sun, as measured by a satellite in earth orbit, is 1353 W/m2. The distance from the earth to the sun is approximately 1.5 x 1011 m. Assuming that the sun radiates evenly in all directions, estimate the diameter of the sun.
Q2 (a) A 12 mm diameter mild steel sphere (k = 42.5 W/m K) is exposed to cooling airflow at 27 "C resulting in the convective coefficient, h = 114 W/m' K. The relevant properties of mild steel are given as follows: Density p= 7850 kg/m . Specific heat c = 475 J/kg K and thermal diffusivity a = 0.043 m/hr Determine: (i) Time required to cool the sphere (lumped parameter system) from 540 °C to 95°C. [7 marks] (ii)...
Heat Transfer problem, ch9 Will give instant thumbs up! Problem 14: Also, after going over example problem 9-2, determine the heat transfer by natural convection for the hot plate facing down with 0 = 30°. Cooling of a Plate in Different Orientations Consider a 0.6-m x 0.6-m thin square plate in a room at 30°C. One side of the plac is maintained at a temperature of 90°C, while the other side is insulated, as shown in Fig. 9-18. Determine the...