Natural Convection
 

Hi All,

I am dealing with buoyancy driven convective heat loss from a cavity by using CFX with the help of 2 different turbulence models (SST and Spalart Allmaras) through a cavity. The cavity is vertical and the opening is downward. I tried to solve this problem with steady state but the results are too high and even they are not converging properly. In transient simulation, can anyone guide me:

1) How I can predict either my simulation is now moving toward steady state or not?
2) how to check the steady state values of heat flux or convective heat loss through cavity, when doing transient simulation?
3) Should I take the average of any value for whole simulation time or for specific time period?

Regards

1) Many free convection flows end up with large scale transient flow features. You cannot capture this with a steady state model. Try running transient.

2) Use a monitor point. This works for steady state flows as well.

3) If the large scale transient flows exist like I refer to in 1) then you cannot reproduce this with a steady state flow. You need to run it transient.