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  • not ABLE TO CALCULATE CL and cd

    Posted by Srinivas K on February 3, 2023 at 6:34 am

    after running my cl abd cd is came Zer0

    Coefficient Total Pressure Viscous Internal
    Cd: 0 0 0 0
    Cd(f): 0 0 0 0
    Cd(r): 0 0 0 0
    Cl: 0 0 0 0
    Cl(f): 0 0 0 0
    Cl(r): 0 0 0 0
    CmPitch: 0 0 0 0
    CmRoll: 0 0 0 0
    CmYaw: 0 0 0 0
    Cs: 0 0 0 0
    Cs(f): 0 0 0 0
    Cs(r): 0 0 0 0

    following is my forcecoeff

    forceCoeffs1
    {
    type forceCoeffs;

    libs (forces);

    writeControl timeStep;
    timeInterval 1;

    log yes;

    patches (STOLFULLGroup);
    rho rhoInf; // Indicates incompressible
    rhoInf 1.225; // Required when rho = rhoInf
    liftDir (0 0 1);
    dragDir (1 0 0);
    CofR (0.72 0 0); // Axle midpoint on ground
    pitchAxis (0 1 0);
    magUInf 17;
    lRef 0.8; // Wheelbase length
    Aref 1.3; // Estimated
    }

    /*
    binField1
    {
    type binField;
    libs (fieldFunctionObjects);
    binModel singleDirectionUniformBin;
    fields (forceCoeff);
    patches (STOLFULLGroup);
    decomposePatchValues true;
    CofR ${..forceCoeffs1.CofR};

    binData
    {
    nBin 20; // output data into 20 bins
    direction (1 0 0); // bin direction
    cumulative yes;
    }
    writeControl timeStep;
    }
    */

    controlDict

    functions
    {
    #include “streamLines”
    #include “wallBoundedStreamLines”
    #include “cuttingPlane”
    #include “forceCoeffs”
    #include “ensightWrite”

    }

    what is wrong iam not able to find

    Barış Bicer replied 1 year, 4 months ago 2 Members · 9 Replies
  • 9 Replies
  • Barış Bicer

    Moderator
    February 3, 2023 at 7:13 am

    ı think that you have to write one by one your patch name instead of group.

    Try and let me know

  • Srinivas K

    Member
    February 3, 2023 at 9:35 am

    I dont have many files in triSurface.

    I have copy the motorBike case nad edit from my side according to my my case.

    i have only one .stl file in triSurface.

  • Barış Bicer

    Moderator
    February 4, 2023 at 6:48 am

    Ok thats why ı said that Please write your .stl file name inside forceCoeff. file / patch directly.

     

     

     

  • Srinivas K

    Member
    February 8, 2023 at 5:10 pm

    i have change the name but its not working

    this is my control dict

    functions
    {
    #include “streamLines”
    #include “wallBoundedStreamLines”
    #include “cuttingPlane”
    #include “forceCoeffs”
    #include “ensightWrite”

    }

    this is my forceCoeffs dict

    /*——————————–*- C++ -*———————————-*\
    | ========= | |
    | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
    | \\ / O peration | Version: v2212 |
    | \\ / A nd | Website: http://www.openfoam.com |
    | \\/ M anipulation | |
    \*—————————————————————————*/

    forceCoeffs1
    {
    type forceCoeffs;

    libs (forces);

    writeControl timeStep;
    timeInterval 1;

    log yes;

    patches (STOLFULLGroup);
    rho rhoInf; // Indicates incompressible
    rhoInf 1.225; // Required when rho = rhoInf
    liftDir (0 0 1);
    dragDir (1 0 0);
    CofR (0.72 0 0); // Axle midpoint on ground
    pitchAxis (0 1 0);
    magUInf 17;
    lRef 0.8; // Wheelbase length
    Aref 1.3; // Estimated
    }

    /*
    binField1
    {
    type binField;
    libs (fieldFunctionObjects);
    binModel singleDirectionUniformBin;
    fields (forceCoeff);
    patches (STOLFULL);
    decomposePatchValues true;
    CofR ${..forceCoeffs1.CofR};

    binData
    {
    nBin 20; // output data into 20 bins
    direction (1 0 0); // bin direction
    cumulative yes;
    }
    writeControl timeStep;
    }

  • Barış Bicer

    Moderator
    February 9, 2023 at 10:28 am

    under forceCoeffs file there is patches ( )  line write there directly your .stl name

  • Srinivas K

    Member
    February 9, 2023 at 10:39 am

    you mean, my geometry name is STOLFULL

    so i should write “STOLFULL.stl” or “STOLFULL”

  • Barış Bicer

    Moderator
    February 12, 2023 at 8:54 pm

    yes if it is name is STOLFUL.stl then write it and try

  • Srinivas K

    Member
    February 13, 2023 at 4:22 am

    I have tried with both name (“STOLFULL”) and (“STOLFULL.stl”)

    but it still not working.

  • Barış Bicer

    Moderator
    February 14, 2023 at 4:45 pm

    can you post here the file content under constant/polyMesh/boundary

     

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