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What is reason for the residuals not able to converge in CHT with...
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+ Residue
+ Combustion
+ Methane
+ Pressure
+ Boundary condition
Posted by
Ogazi James
What is reason for the residuals not able to converge in CHT with...
E.g. your developing flame could be just unsteady....
And, please, if I'm right in my guess that this is a steady-state simulation (cannot be seen clearly from the PPT), then please activate the two check boxes: 1) pseudo-transient method 2) High-order term relaxation. The (shitty) Fluent steady-state solver has not a good convergence characterstics at all. Therefore nowadays the default (even in Fluent) is the pseudo-transient method for steady-state flow computations.
Furthermore with pseudo-transient method you should activate (if not the default) the different pseudo-transient time-step selection for solid materials, thereby allowing the CFD solver to solve the energy equation (for a steady-state solution) in the solid domains with a much higher pseudo-timescale, then the convection problem in the fluid domain, thereby treating the much larger timescales of solid material heat conduction appropriately.
E.g. your developing flame could be just unsteady....
And, please, if I'm right in my guess that this is a steady-state simulation (cannot be seen clearly from the PPT), then please activate the two check boxes: 1) pseudo-transient method 2) High-order term relaxation. The (shitty) Fluent steady-state solver has not a good convergence characterstics at all. Therefore nowadays the default (even in Fluent) is the pseudo-transient method for steady-state flow computations.
Furthermore with pseudo-transient method you should activate (if not the default) the different pseudo-transient time-step selection for solid materials, thereby allowing the CFD solver to solve the energy equation (for a steady-state solution) in the solid domains with a much higher pseudo-timescale, then the convection problem in the fluid domain, thereby treating the much larger timescales of solid material heat conduction appropriately.
E.g. your developing flame could be just unsteady....
And, please, if I'm right in my guess that this is a steady-state simulation (cannot be seen clearly from the PPT), then please activate the two check boxes:
1) pseudo-transient method
2) High-order term relaxation.
The (shitty) Fluent steady-state solver has not a good convergence characterstics at all. Therefore nowadays the default (even in Fluent) is the pseudo-transient method for steady-state flow computations.
Furthermore with pseudo-transient method you should activate (if not the default) the different pseudo-transient time-step selection for solid materials, thereby allowing the CFD solver to solve the energy equation (for a steady-state solution) in the solid domains with a much higher pseudo-timescale, then the convection problem in the fluid domain, thereby treating the much larger timescales of solid material heat conduction appropriately.
Best regards,
Dr. Th. Frank.
E.g. your developing flame could be just unsteady....
And, please, if I'm right in my guess that this is a steady-state simulation (cannot be seen clearly from the PPT), then please activate the two check boxes:
1) pseudo-transient method
2) High-order term relaxation.
The (shitty) Fluent steady-state solver has not a good convergence characterstics at all. Therefore nowadays the default (even in Fluent) is the pseudo-transient method for steady-state flow computations.
Furthermore with pseudo-transient method you should activate (if not the default) the different pseudo-transient time-step selection for solid materials, thereby allowing the CFD solver to solve the energy equation (for a steady-state solution) in the solid domains with a much higher pseudo-timescale, then the convection problem in the fluid domain, thereby treating the much larger timescales of solid material heat conduction appropriately.
Best regards,
Dr. Th. Frank.
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Thomas Frank Thanks a lot sir.
Yes I am doing steady state simulation only.
I will make these changes and will check the results.
Thomas Frank Thanks a lot sir.
Yes I am doing steady state simulation only.
I will make these changes and will check the results.
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