Author: Chia-Hsun Hsieh, Cornell University

Probl=
em Specification

1. Pre-Analysis & Start-Up

2. Geometry

3. Mesh

4. Physics Set=
up

5. Numerical Solution

6. Numerical Results

7. Verification &=
; Validation

Exercises

Comments

Consider a pair of concentric cylinders with a ** height** of

Assume only the inner surface of the larger, hollow cylinder and the cyl= indrical surface of the smaller cylinder are emitting radiation. Also assum= e the surfaces are gray and diffuse. The net radiation of an emitting surfa= ce of this concentric cylinder, two-surface enclosure is give below:

In this convention, the **<=
em>subscript "1"** denotes the smaller cylinder and the =
*subscript "2"*** denotes the larger, hollow cylinder. Since this is a two-surface=
enclosure problem, we can expect the view factor for each surface to be 1. Al=
l the radiation emitted by one surface is intercepted by the other surface.=
The notation of the above equation is the net radiation of the smaller cyl=
inder.**

The analytic solution shows the net radiation of the smaller cylinder is=
*-0.428 watts***.**

Solve this problem with the same procedure for the shell and specimen tu=
torial. First solve the ** =
steady state** model and transfer the data to

From the tabular data, the net radiation of the smaller cylinder is ** -0.423 watts** at the step end time. ANSYS result shows a