Using simulation results as time-resolved boundary condition

vainilreb · November 15, 2012, 06:52

Hi,

I've had the idea of simulating a very small area with a really fine mesh and then take the results as input for a more coarse simulation in a larger area. But I don't simply want to define a start condition at the junction but to let them vary by time, just as calculated in the fine simulation before. I hope you get what I mean, I don't really know how to explain it in English. Is this possible and if so, how?

I really hope anyone can help me.

Robert

vainilreb · November 19, 2012, 02:55

Isn't there any possibility to do this?

In my case there is ammonia flowing into a room filled with air at high inlet velocities. Due to the high gradient in the gas concentrations at the inlet I have to keep the cell size extremely tiny. This makes the time step become extremely tiny. So I thought about calculating the process of gas inflow in a smaller control volume with very fine cells around the outlet and then use this control volume as inlet for a more coarse and faster calculation of the environmental setup.

Isn't this possible?

November 15, 2012, 06:52	Using simulation results as time-resolved boundary condition	#1
vainilreb Member Robert Join Date: Aug 2012 Location: Berlin Posts: 74 Rep Power: 14	Hi, I've had the idea of simulating a very small area with a really fine mesh and then take the results as input for a more coarse simulation in a larger area. But I don't simply want to define a start condition at the junction but to let them vary by time, just as calculated in the fine simulation before. I hope you get what I mean, I don't really know how to explain it in English. Is this possible and if so, how? I really hope anyone can help me. Robert

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November 19, 2012, 02:55		#2
vainilreb Member Robert Join Date: Aug 2012 Location: Berlin Posts: 74 Rep Power: 14	Isn't there any possibility to do this? In my case there is ammonia flowing into a room filled with air at high inlet velocities. Due to the high gradient in the gas concentrations at the inlet I have to keep the cell size extremely tiny. This makes the time step become extremely tiny. So I thought about calculating the process of gas inflow in a smaller control volume with very fine cells around the outlet and then use this control volume as inlet for a more coarse and faster calculation of the environmental setup. Isn't this possible?