How to call residual in User CEL function/ User Junction Box

lostking18 · April 8, 2019, 15:59

Hi, guys

I need to implement residual of the previous (Pseudo) time step in the User CEL function/User Junction Box via User Fortran to carry on my simulation. However I cannot find residual in the Variable list in CFX pre. Is there any method that we can call the residual of the previous (Pseudo) time step in User Fortran? I’ve already tick the “Output Equation Residual” option in the Output control and use
Resid normalisation type = 0
in the expert parameter to ensure the residual at each nodes will be output in the results file.

Thank you very much!

Opaque · April 8, 2019, 16:48

There is no documented API to access the equation residuals. Neither via CEL function, and even less Junction Box.

May I ask what is your objective with handing the residuals? Non-linear iterations modifications of some sort?

lostking18 · April 11, 2019, 06:55

Hi, Oqaque,

Thank you for your answering. I'm using residual to do some validation for the solver. It is frustrating that we cannot handling residual in CFX. T_T

April 8, 2019, 15:59	How to call residual in User CEL function/ User Junction Box	#1
lostking18 Member phd Join Date: Oct 2013 Posts: 76 Rep Power: 13	Hi, guys I need to implement residual of the previous (Pseudo) time step in the User CEL function/User Junction Box via User Fortran to carry on my simulation. However I cannot find residual in the Variable list in CFX pre. Is there any method that we can call the residual of the previous (Pseudo) time step in User Fortran? I’ve already tick the “Output Equation Residual” option in the Output control and use Resid normalisation type = 0 in the expert parameter to ensure the residual at each nodes will be output in the results file. Thank you very much!

April 8, 2019, 16:48		#2
Opaque Senior Member Join Date: Jun 2009 Posts: 1,880 Rep Power: 33	There is no documented API to access the equation residuals. Neither via CEL function, and even less Junction Box. May I ask what is your objective with handing the residuals? Non-linear iterations modifications of some sort? lostking18 likes this.

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April 11, 2019, 06:55		#3
lostking18 Member phd Join Date: Oct 2013 Posts: 76 Rep Power: 13	Hi, Oqaque, Thank you for your answering. I'm using residual to do some validation for the solver. It is frustrating that we cannot handling residual in CFX. T_T