chtMultiRegionSimpleFoam for high velocity and pressures

prameelar · March 28, 2014, 22:10

Hi,

I am trying to simulate conjugate heat transfer for typhoon vane which is operating at high initial boundary conditions like U~2--m/s, T~1200K and Pressure~10 atm. Initially i have started with Simple cylinder case with hot air flowing outside and cold air flowing inside the cylinder.

I am using Ubuntu 13.10 and OpenFOAM- 2.3.

I was able to simulate to certain velocity (~65 m/s, 1000K) but after that, If I try to increase the velocity then the solver id crashing with the following error,

Code:

--> FOAM FATAL ERROR: 
Maximum number of iterations exceeded

    From function thermo<Thermo, Type>::T(scalar f, scalar T0, scalar (thermo<Thermo, Type>::*F)(const scalar) const, scalar (thermo<Thermo, Type>::*dFdT)(const scalar) const, scalar (thermo<Thermo, Type>::*limit)(const scalar) const) const
    in file /home/opencfd/OpenFOAM/OpenFOAM-2.3.0/src/thermophysicalModels/specie/lnInclude/thermoI.H at line 76.

FOAM aborting

I have tried all the possible options to my knowledge and the forum support but still am not able to solve the problem.

1. I have tried using different boundary conditions
2. improved Mesh
3. relaxation factors, fvsolution settings, fvSchemes.. etc.

Is there anyone who was able to solve the problem for high velocities using Multi Region Solver?

Thank you,
Pam.

vasava · March 31, 2014, 05:16

Are you using K-epsilon model. If so try with SST model, keep the relative tolerance really low (until your flow gets converged) and use linear gauss scheme. All these suggestion with significantly increase your calculation time.

March 28, 2014, 22:10	chtMultiRegionSimpleFoam for high velocity and pressures	#1
prameelar New Member Pam Join Date: Feb 2011 Posts: 15 Rep Power: 15	Hi, I am trying to simulate conjugate heat transfer for typhoon vane which is operating at high initial boundary conditions like U~2--m/s, T~1200K and Pressure~10 atm. Initially i have started with Simple cylinder case with hot air flowing outside and cold air flowing inside the cylinder. I am using Ubuntu 13.10 and OpenFOAM- 2.3. I was able to simulate to certain velocity (~65 m/s, 1000K) but after that, If I try to increase the velocity then the solver id crashing with the following error, Code: --> FOAM FATAL ERROR: Maximum number of iterations exceeded From function thermo<Thermo, Type>::T(scalar f, scalar T0, scalar (thermo<Thermo, Type>::F)(const scalar) const, scalar (thermo<Thermo, Type>::dFdT)(const scalar) const, scalar (thermo<Thermo, Type>::*limit)(const scalar) const) const in file /home/opencfd/OpenFOAM/OpenFOAM-2.3.0/src/thermophysicalModels/specie/lnInclude/thermoI.H at line 76. FOAM aborting I have tried all the possible options to my knowledge and the forum support but still am not able to solve the problem. 1. I have tried using different boundary conditions 2. improved Mesh 3. relaxation factors, fvsolution settings, fvSchemes.. etc. Is there anyone who was able to solve the problem for high velocities using Multi Region Solver? Thank you, Pam. __________________ Pam

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March 31, 2014, 05:16		#2
vasava Senior Member Paritosh Vasava Join Date: Oct 2012 Location: Lappeenranta, Finland Posts: 732 Rep Power: 23	Are you using K-epsilon model. If so try with SST model, keep the relative tolerance really low (until your flow gets converged) and use linear gauss scheme. All these suggestion with significantly increase your calculation time.