Learning Forum

[jan-henrik.rieger]

I am simulating the flow and convective heat transfer of an impinging jet from a single round nozzle. I would like to make use of the symmetry of the domain to reduce its size. 

 

However, when I simulate the 'pie slice', as shown in the image below, and determine the convective heat transfer coefficient, the first measurement point—which is effectively at the origin—drops sharply, even though this is where the maximum heat transfer physically occurs. On further examination of the variables that are included in the heat transfer coefficients, I noticed that the heat flux also shows this decrease and is therefore the variable that has not actually been calculated correctly. 

My question is: what could be causing this? Or, more specifically, how is the heat flux calculated to result in such a drop? Is it because the first cell is too narrow, or is there another way to explain this drop?

 

Simulating half the domain yields a physically correct result that corresponds to that of the full domain.

 

I would be very grateful for an explanation, or perhaps some references to further reading or similar resources.

 

Best regards,

Jan-Henrik

[Rob]

Can you plot wall shear, pressure etc on the wall? Also velocity on symmetry & equivalent plane in the 3d model. Plot with node values off.