Interogating Solution Values at Past Time Steps

July 29, 2002, 17:58

I think I understand that Fluent can report "monitored" forces or field values on surfaces throughout time dependent calculations. However, I wondered if I can actually recover the entire solution (vector fields, etc.) for previous time steps in the series. I am trying to see how a flow evolves temporally. Say I solve it to the t=30s mark, could I actually go back to see what the vector field was at t=26s mark? Or do I have to solve my flow for t=26s, then t=27s, ..... , to t=30s?

Many thanks for any input!

Rupp.

July 31, 2002, 03:07

You have access to data from the last couple of time steps (See UDF Users Guide, FLUENT 6, Feb 2002). Anything beyond that and you'll have to write your data to a file. You could also use user-defined scalars to store variable fields, e.g., store three components of velocity with three UDS's. Use a UDF to execute the transfer of data to a UDS(e.g., C_UDSI(c,t,i) = C_U(c,t), etc.) at a specific time-step or count.

July 31, 2002, 10:20

Thank You very much for the help.

July 29, 2002, 17:58	Interogating Solution Values at Past Time Steps	#1
Rupp Carriveau Guest Posts: n/a	I think I understand that Fluent can report "monitored" forces or field values on surfaces throughout time dependent calculations. However, I wondered if I can actually recover the entire solution (vector fields, etc.) for previous time steps in the series. I am trying to see how a flow evolves temporally. Say I solve it to the t=30s mark, could I actually go back to see what the vector field was at t=26s mark? Or do I have to solve my flow for t=26s, then t=27s, ..... , to t=30s? Many thanks for any input! Rupp.

July 31, 2002, 03:07	Re: Interogating Solution Values at Past Time Step	#2
Lanre Guest Posts: n/a	You have access to data from the last couple of time steps (See UDF Users Guide, FLUENT 6, Feb 2002). Anything beyond that and you'll have to write your data to a file. You could also use user-defined scalars to store variable fields, e.g., store three components of velocity with three UDS's. Use a UDF to execute the transfer of data to a UDS(e.g., C_UDSI(c,t,i) = C_U(c,t), etc.) at a specific time-step or count.

July 31, 2002, 10:20	Re: Interogating Solution Values at Past Time Step	#3
Rupp Carriveau Guest Posts: n/a	Thank You very much for the help.

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