CFD Online Discussion Forums - [swak4Foam] funkydoCalc issue with snGrad

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funkydoCalc issue with snGrad

Hello

I have n issue with snGrad usage with funkydocalc.

With swak4foam

I gave :

Code:

functions(

 

   NusseltNumber_hot 

   { 

    type          patchExpression; 

     outputControl  timeStep; 

     outputInterval 1; 

        patches ( 

                w_l 

               ); 

    verbose true; 

        variables ( 

                "Tsat=300.1;" 

                "ln2D=3.065;"      //length(.08)/k(.0261)  

               ); 

    expression "ln2D*snGrad(T)/(T-Tsat)"; 

        accumulations ( 

                    average 

            );  

   }

);

------------------------------------------------------

This gave me a Nusselt No. of 56.02 (neglect scaling)
.

With all data in disk I tried to obtian the same using funkyDoCalc as:

Code:

    NusseltNumber_hot 

   { 

    valueType                        patch; 

        patchName                        w_l; 

        variables (  

                        "Tsat=300.1;" 

                        "ln2D=3.065;"      //length(.08)/k(.0261)  

         ); 

    expression                      "ln2D*snGrad(T)/(T-Tsat)"; 

        accumulations ( 

                    max 

                  );  

   }

-----------------------------------------------------------
Which is giving me 0 as output for max/min/average

I read in:
https://sourceforge.net/p/openfoam-e...2.1_v2.x/tree/

that the snGrad doesnt work when data is in disc and needs to be temporarily loaded. Could anyone explain on what to be done

Quote:

Originally Posted by manuc (Post 614108)

that the snGrad doesnt work when data is in disc and needs to be temporarily loaded. Could anyone explain on what to be done

Quick answer, although really late by now: according to the information you've found, you must use this while the solver is running and cannot use it with funkyDoCalc.

Quote:

Originally Posted by wyldckat (Post 676639)

Quick answer, although really late by now: according to the information you've found, you must use this while the solver is running and cannot use it with funkyDoCalc.

Yep. Reason is that for such calculations to work correctly funkyDoCalc would have to call correctBoundaryConditions() on loaded fields. And that has the strong potential to crash if a boundary condition needs another field in memory and doesn't find it.