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    OpenFOAM可压缩管流边界条件设置

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    • 疾风GAVIN
      疾风GAVIN 最后由 李东岳 编辑

      新手入门，请教OpenFOAM可压缩管流边界条件设置
      进口条件：Ma=0.6 P=101325(静压) T=300K（静温）
      出口条件：P=101325(静压) T=300K（静温）
      壁面：noSlip
      使用的Foam:sonicFoam

      在设置的时候不知道应该选用什么样的边界条件和求解器才能达到想要的效果，使用进口固定值出口零梯度又会发散，残差很大

      P

      
dimensions      [1 -1 -2 0 0 0 0];

internalField   uniform 101325;

boundaryField
{
    inlet
    {
        type            fixedValue;
        value           uniform 101325;
    }

    outlet
    {
	type            zeroGradient;
    }

    sym
    {
        type            symmetryPlane;
    }

    wall
    {
        type            zeroGradient;
    }
}

      U

      dimensions      [0 1 -1 0 0 0 0];

internalField   uniform (208.3 0 0);

boundaryField
{
    inlet
    {
        type            fixedValue;
        value           uniform (208.3 0 0);
    }

    outlet
    {
        type            zeroGradient;
    }

    sym
    {
        type            symmetryPlane;
    }

    wall
    {
        type            noSlip;
    }
}

      T

      dimensions      [0 0 0 1 0 0 0];

internalField   uniform 300;

boundaryField
{
    inlet
    {
        type            fixedValue;
        value           uniform 300;
    }

    outlet
    {
        type            zeroGradient;
    }

    sym
    {
        type            symmetryPlane;
    }

    wall
    {
        type            zeroGradient;
    }
}

      thermophysicalProperties

      thermoType
{
    type            hePsiThermo;
    mixture         pureMixture;
    transport       const;
    thermo          hConst;
    equationOfState perfectGas;
    specie          specie;
    energy          sensibleInternalEnergy;
}

mixture
{
    specie
    {
        molWeight       28.9;
    }
    thermodynamics
    {
        Cp              2.5;
        Hf              0;
    }
    transport
    {
        mu              0;
        Pr              1;
    }
}

      turbulenceProperties

      simulationType  laminar;

      controlDict

      application     sonicFoam;

startFrom       startTime;

startTime       0;

stopAt          endTime;

endTime         10;

deltaT          5e-8;

writeControl    runTime;

writeInterval   1e-6;

purgeWrite      0;

writeFormat     ascii;

writePrecision  6;

writeCompression off;

timeFormat      general;

timePrecision   6;

runTimeModifiable true;

functions
{
    libs            ("libfieldFunctionObjects.so");

    Ma
    {
        type            MachNo;
        executeControl  writeTime;
        writeControl    writeTime;
    }
}

      fvSchemes

      ddtSchemes
{
    default         Euler;
}

gradSchemes
{
    default         Gauss linear;
}

divSchemes
{
    default         none;
    div(phi,U)      Gauss upwind;
    div(phid,p)     Gauss limitedLinear 1;
    div(phi,e)      Gauss limitedLinear 1;
    div(phi,K)      Gauss limitedLinear 1;
    div(phiv,p)     Gauss limitedLinear 1;
    div(((rho*nuEff)*dev2(T(grad(U))))) Gauss linear;
}

laplacianSchemes
{
    default         Gauss linear corrected;
}

interpolationSchemes
{
    default         linear;
}

snGradSchemes
{
    default         corrected;
}

      fvSolution

      solvers
{
    "p.*"
    {
        solver          smoothSolver;
        smoother        symGaussSeidel;
        tolerance       1e-06;
        relTol          0;
    }

    "(U|e).*"
    {
        $p;
        tolerance       1e-05;
        relTol          0;
    }

    "rho.*"
    {
        solver          PCG;
        preconditioner  DIC;
        tolerance       1e-05;
        relTol          0;
    }
}

PIMPLE
{
    nOuterCorrectors 2;
    nCorrectors      1;
    nNonOrthogonalCorrectors 0;
}

      终端

      Create time

Create mesh for time = 0


PIMPLE: No convergence criteria found


PIMPLE: No corrector convergence criteria found
        Calclations will do 2 corrections

Reading thermophysical properties

Selecting thermodynamics package 
{
    type            hePsiThermo;
    mixture         pureMixture;
    transport       const;
    thermo          hConst;
    equationOfState perfectGas;
    specie          specie;
    energy          sensibleInternalEnergy;
}

Reading field U

Reading/calculating face flux field phi

Creating turbulence model

Selecting turbulence model type laminar
Selecting laminar stress model Stokes
Creating field kinetic energy K

No MRF models present

No finite volume options present

Starting time loop

Time = 1e-07

Courant Number mean: 0.0179457 max: 1.04496
diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
PIMPLE: Iteration 1
smoothSolver:  Solving for Ux, Initial residual = 5.30982e-06, Final residual = 5.30982e-06, No Iterations 0
smoothSolver:  Solving for Uy, Initial residual = 1, Final residual = 0.0354675, No Iterations 1000
smoothSolver:  Solving for Uz, Initial residual = 1, Final residual = 0.100472, No Iterations 1000
smoothSolver:  Solving for e, Initial residual = 1, Final residual = 7.6181, No Iterations 1000
#0  Foam::error::printStack(Foam::Ostream&) at ??:?
#1  Foam::sigFpe::sigHandler(int) at ??:?
#2  ? in "/lib/x86_64-linux-gnu/libc.so.6"
#3  Foam::symGaussSeidelSmoother::smooth(Foam::word const&, Foam::Field<double>&, Foam::lduMatrix const&, Foam::Field<double> const&, Foam::FieldField<Foam::Field, double> const&, Foam::UPtrList<Foam::lduInterfaceField const> const&, unsigned char, int) at ??:?
#4  Foam::symGaussSeidelSmoother::smooth(Foam::Field<double>&, Foam::Field<double> const&, unsigned char, int) const at ??:?
#5  Foam::smoothSolver::solve(Foam::Field<double>&, Foam::Field<double> const&, unsigned char) const at ??:?
#6  Foam::fvMatrix<double>::solveSegregated(Foam::dictionary const&) at ??:?
#7  Foam::fvMatrix<double>::solve(Foam::dictionary const&) in "/home/jifeng/OpenFOAM/OpenFOAM-6/platforms/linux64GccDPInt32Opt/bin/sonicFoam"
#8  Foam::fvMatrix<double>::solve() in "/home/jifeng/OpenFOAM/OpenFOAM-6/platforms/linux64GccDPInt32Opt/bin/sonicFoam"
#9  ? in "/home/jifeng/OpenFOAM/OpenFOAM-6/platforms/linux64GccDPInt32Opt/bin/sonicFoam"
#10  __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6"
#11  ? in "/home/jifeng/OpenFOAM/OpenFOAM-6/platforms/linux64GccDPInt32Opt/bin/sonicFoam"

      为真理而战

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      • 疾风GAVIN
        疾风GAVIN 最后由 编辑

        替代文字

        为真理而战

        1 条回复 最后回复 回复 引用
        • 李东岳
          李东岳 管理员 最后由 李东岳 编辑

          速度方向对么，你的速度迭代了很多次，

          另外，你的mu是0，应该是壁面：slip

          Courant Number mean: 0.0179457 max: 1.04496
          同时减小你的时间步长

          CFD高性能服务器 http://dyfluid.com/servers.html
          2023年，线下CFD课，预热一下 http://dyfluid.com/class.html

          疾风GAVIN 1 条回复 最后回复 回复 引用
          • 疾风GAVIN
            疾风GAVIN @李东岳 最后由 编辑

            @东岳
            谢谢李老师，我检查了一下速度方向，是正确的，但mu是0是因为我参照的tutorials里面的给定方法，自己也不太清楚具体应该怎么修改，这个mu和之前算incom里面的nu是一个意思吗？
            我刚刚在自己电脑上重新设置了一下，修改该了一些边界条件，用的是rhoCentralFoam,现在没有发散并且正在计算了，时间步长我修改了，可以计算也没有发散
            P

            dimensions      [1 -1 -2 0 0 0 0];

internalField   uniform 101325;

boundaryField
{
    inlet
    {
        type            fixedValue;
        value           uniform 101325;
    }

    outlet
    {
        type            zeroGradient;
        phi             phi;
        rho             rho;
        psi             thermo:psi;
        U               U;
        gamma           1.4;
        inletOutlet     false;
        correctSupercritical true;
        lInf            0;
        fieldInf        101325;
        value           uniform 101325;
    }

    sym
    {
        type            symmetryPlane;
    }

    wall
    {
        type            zeroGradient;
    }
}

            U

            dimensions      [0 1 -1 0 0 0 0];

internalField   uniform (208.3 0 0);

boundaryField
{
    inlet
    {
        type            fixedValue;
        value           uniform (208.3 0 0);
    }

    outlet
    {
        type           zeroGradient;
        inletValue     uniform (0 0 0);
        value          $internalField;
    }

    sym
    {
        type            symmetryPlane;
    }

    wall
    {
        type            noSlip;
    }

            T

            dimensions      [0 0 0 1 0 0 0];

internalField   uniform 300;

boundaryField
{
    inlet
    {
        type            fixedValue;
        value           uniform 300;
    }

    outlet
    {
        type            zeroGradient;
    }

    sym
    {
        type            symmetryPlane;
    }

    wall
    {
        type            zeroGradient;
    }

            thermophysicalProperties

            thermoType
{
    type            hePsiThermo;
    mixture         pureMixture;
    transport       const;
    thermo          hConst;
    equationOfState perfectGas;
    specie          specie;
    energy          sensibleInternalEnergy;
}

mixture // air at room temperature (293 K)
{
    specie
    {
        molWeight   28.9;
    }
    thermodynamics
    {
        Cp          1005;
        Hf          0;
    }
    transport
    {
        mu          0;
        Pr          0.71;
    }
}

            turbulenceProperties

            simulationType laminar;

            我下面想进行有粘可压计算，但我不知道0文件里面增加的alphat、k、nut、omega的初始条件和边界值具体应该给多少，请问李老师这个有什么可以参考的吗？

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            • 李东岳
              李东岳 管理员 最后由 编辑

              mu和nu就是粘度，

              0文件里面增加的alphat、k、nut、omega的初始条件和边界值具体应该给多少

              这个不好弄。k和omega都给固定值进口就可以，具体数值可以算一下：$k=1.5u'^2,\varepsilon=\frac{C_\mu^{0.75}k^{1.5}}{\kappa l},\kappa=0.4, \omega=\frac{k}{0.09\varepsilon}$，其中$l$为参考长度（自定义取值）

              CFD高性能服务器 http://dyfluid.com/servers.html
              2023年，线下CFD课，预热一下 http://dyfluid.com/class.html

              疾风GAVIN 1 条回复 最后回复 回复 引用
              • 疾风GAVIN
                疾风GAVIN @李东岳 最后由 编辑

                @东岳
                恩恩，好的，我按照老师的思路再来来设置一下，谢谢李老师

                为真理而战

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                • E
                  Exthan 最后由 编辑

                  变物性？

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                  • 疾风GAVIN
                    疾风GAVIN 最后由 编辑

                    不是的，后面我用komegaSST算了一下这个模型，吧压力求解器改成了PCG之后就收敛了，而且结果比较满意，希望对遇到同样问题的朋友也有参考价值

                    为真理而战

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