Radiation between surfaces forming a enclosure#

The Radiation between surfaces forming a enclosure block describes heat exchange of radiation between gray surfaces forming a closed system.

Heat flux (1) :

(1)#\[Q=\frac{\sigma \cdot (T_1^4-T_2^4)\cdot F_1 \cdot \phi_{12}}{1+(\frac{1-\epsilon _1}{\epsilon _1})\cdot \phi_{12}+(\frac{1-\epsilon _2}{\epsilon _2})\cdot \phi_{21}}\]

where:

\(\sigma\) – the Stefan-Boltzmann constant;

\(F_1\) - area of radiating surface of body 1;

\(\epsilon _1\) - degree of blackness of the body 1 ( 0 < \(\epsilon _1\) ≤ 1);

\(\epsilon _2\) - degree of blackness of the body 2 ( 0 < \(\epsilon _2\) ≤ 1);

\(\phi _{12}\) - angular coefficient from body 1 to body 2 ( 0 < \(\phi _{12}\) ≤ 1);

\(\phi _{21}\) - angular coefficient from body 2 to body 1 (0 <\(\phi _{21}\) ≤ 1);

\(T_1\) - temperature at the block inlet;

\(T_2\) - temperature at the block outlet.

It is required to take into account the following equality when filling in block properties (2) :

(2)#\[F_1 \cdot \phi _{12}=F_2 \cdot \phi _{21}\]

where \(F_2\) - area of radiating surface of body 2.

1. Properties#

Property	Default value	Description	Units of measurement
Emitting area of surface 1	1.0	-	m\(^2\)
Emitting area of surface 2	1.0	-	m\(^2\)
Emissivity of surface 1	0.8	-	-
Emissivity of surface 2	0.7	-	-
Shape factor from surface 1 to surface 2	0.8	-	-

2. Inputs and outputs#

Parameters	Input/Output	Description	Units of measurement	Port type
Input	Input	-	-	Heat exchange
Output	Output	-	-	Heat exchange

In order to see the connection capabilities of the block, you need to go to page Description of block ports