An electric heater with a capacity P is usedto heat air in a spherical chamber. Theinside radius
Question:
An electric heater with a capacity P is usedto heat air in a spherical chamber. Theinside radius is Ri outside radius Ro andthe conductivity is k. At the inside
surface heat is exchanged by convection.The inside heat transfer coefficient is h .
Heat loss from the outside surface is by radiation. The surroundings temperature is Tsur and the surfaceemissivity is epsnot . Assuming one-dimensional steady state conduction,
use a simplified radiation model to determine:
[a] The temperature distribution in the spherical wall.
[b] The inside air temperatures for the following conditions:
h = 6.5W/m2 C , P = 1, 500 W, epsnot = 0.81,
Tsur=18c
k = 2.4W/moC,Ri = 10 cm, Ro= 14 cm.
Principles of heat transfer
ISBN: 978-0495667704
7th Edition
Authors: Frank Kreith, Raj M. Manglik, Mark S. Bohn