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Using C_T_M1 in the UDf to access previous time step temperatures
Problem for resolution1:
Proper use of C_T_M1 macro in the UDF to access previous time step temperature values.
Problem for resolution 2:
A case file that has UDF initialization and some other udfs with global variables being initialized through DEFINE_INITIALIZE is saved with data after running few iterations. If the case/data files are opened later and attempted to run further, give error message.
To use C_T_M1 (c,t) macro, the uds must be activated. I am not too sure if this holds true for temperature only or all the variables, but I checked that without activating uds, C_T_M1 was returning junk values in the UDF. So I activated 1 uds equation. I have not assigned any material properties etc and am not soving the UDS equation either. But this resulted in the macro C_T_M1 returning correct values. I did not check for other *_M1 macros.
The problem is due to initialization. This can be avoided by
1. read only the case file
2. initialize the solution
3 then read the saved data file
4 iterate further.