Radiation properties with perforated sheet
 

Hello everybody,

I would like to simulate a heat transfer between two wall:

Wall 1:
- Hot temperature 473K
- Internal emissivity =0,8 (old steel)

Wall 2:
- Perforated plate (modelized as a plan, without hole)
- Distance between the wall 1 = 200mm
- Material steel
- Internal emissivity = 0,8

The model is a rectangle where:
- Side left of rectangle is wall1
- Front face = velocity inlet (2m/s)
- Side right = adiabatic wall (should be the air)
- back face = pressure outlet (gauge pressure =0)
- Top face = adiabatic wall (should be the air)
- Bottom face = adiabatic wall (should be the air)
- Wall 2 inside the rectangle with coupled BC

The purpose of this simulation is to know how the wall 2 is heating by the hot wall

I have some questions:

1) Someone could confirmed that as the steel is opaque material, so the absorption (1/m) is equal to the emissivity (0,8) ? (I need the information for discrete ordinate model)

2) My model have a velocity inlet of 2m/s so the simulation is incompressible but when I looked between the static temperature and total temperature the iso contour are different. But they should be the same ?

3) The wall 2 is a perforated sheet, where the flow is passing parallel to the perforated sheet, should I define the perforated sheet as porous jump ?

Thancks very much for any answer... :):):)

Fredom