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kennyadapter

@cfd_fly 您好，，有时间可以再分享一下嘛？非常感谢

kennyadapter

请问您解决了吗
我的数据也波动很大

kennyadapter

@东岳在 200万网格管道流qDNS并行算力测试中说：

东岳老师，那怎么调整带宽呢？有什么方法，或者需要更换什么配件吗？

kennyadapter

@东岳
这是我44核心的log文件的最后几个时间步：之前的迭代次数也差不多：


Time = 9.8

Courant Number mean: 0.733368 max: 1.27353
GAMG:  Solving for p, Initial residual = 0.0998056, Final residual = 0.00082233, No Iterations 6
time step continuity errors : sum local = 4.80691e-07, global = 1.99762e-20, cumulative = 1.59798e-17
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000123775
GAMG:  Solving for p, Initial residual = 0.0809999, Final residual = 0.000584259, No Iterations 6
time step continuity errors : sum local = 3.45394e-07, global = 5.63939e-20, cumulative = 1.60362e-17
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000120435
GAMG:  Solving for p, Initial residual = 0.0189678, Final residual = 9.4483e-07, No Iterations 39
time step continuity errors : sum local = 5.51633e-10, global = 3.45318e-20, cumulative = 1.60707e-17
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000119638
ExecutionTime = 170.51 s  ClockTime = 171 s

Time = 9.9

Courant Number mean: 0.73339 max: 1.27886
GAMG:  Solving for p, Initial residual = 0.100098, Final residual = 0.000824461, No Iterations 6
time step continuity errors : sum local = 4.82558e-07, global = 8.66441e-20, cumulative = 1.61574e-17
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000123823
GAMG:  Solving for p, Initial residual = 0.0809731, Final residual = 0.000577791, No Iterations 6
time step continuity errors : sum local = 3.42103e-07, global = 4.07868e-20, cumulative = 1.61981e-17
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000120471
GAMG:  Solving for p, Initial residual = 0.0189619, Final residual = 9.31189e-07, No Iterations 39
time step continuity errors : sum local = 5.44568e-10, global = 7.2382e-20, cumulative = 1.62705e-17
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000119674
ExecutionTime = 172.22 s  ClockTime = 172 s

Time = 10

Courant Number mean: 0.733413 max: 1.27933
GAMG:  Solving for p, Initial residual = 0.0999699, Final residual = 0.000818608, No Iterations 6
time step continuity errors : sum local = 4.79761e-07, global = 8.13808e-20, cumulative = 1.63519e-17
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.00012387
GAMG:  Solving for p, Initial residual = 0.081007, Final residual = 0.000576888, No Iterations 6
time step continuity errors : sum local = 3.41793e-07, global = 5.45899e-20, cumulative = 1.64065e-17
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000120508
GAMG:  Solving for p, Initial residual = 0.0189675, Final residual = 9.02577e-07, No Iterations 39
time step continuity errors : sum local = 5.28191e-10, global = 1.77208e-20, cumulative = 1.64242e-17
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.00011971
ExecutionTime = 173.99 s  ClockTime = 174 s

End

这是我32核心的：


Time = 9.8

Courant Number mean: 0.733369 max: 1.27363
GAMG:  Solving for p, Initial residual = 0.0998053, Final residual = 0.000728134, No Iterations 6
time step continuity errors : sum local = 4.26347e-07, global = 1.16708e-20, cumulative = 5.86486e-18
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000123776
GAMG:  Solving for p, Initial residual = 0.0810209, Final residual = 0.00054928, No Iterations 6
time step continuity errors : sum local = 3.24835e-07, global = 4.55333e-20, cumulative = 5.9104e-18
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000120434
GAMG:  Solving for p, Initial residual = 0.0189497, Final residual = 8.88034e-07, No Iterations 38
time step continuity errors : sum local = 5.18253e-10, global = 2.24608e-20, cumulative = 5.93286e-18
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000119638
ExecutionTime = 167.35 s  ClockTime = 167 s

Time = 9.9

Courant Number mean: 0.73339 max: 1.27894
GAMG:  Solving for p, Initial residual = 0.100093, Final residual = 0.00073128, No Iterations 6
time step continuity errors : sum local = 4.28756e-07, global = 1.40838e-20, cumulative = 5.94694e-18
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000123823
GAMG:  Solving for p, Initial residual = 0.0809929, Final residual = 0.000542798, No Iterations 6
time step continuity errors : sum local = 3.21522e-07, global = -2.66223e-20, cumulative = 5.92032e-18
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000120471
GAMG:  Solving for p, Initial residual = 0.0189464, Final residual = 8.9418e-07, No Iterations 38
time step continuity errors : sum local = 5.22767e-10, global = 2.26167e-20, cumulative = 5.94294e-18
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000119674
ExecutionTime = 169.06 s  ClockTime = 169 s

Time = 10

Courant Number mean: 0.733413 max: 1.27934
GAMG:  Solving for p, Initial residual = 0.0999826, Final residual = 0.000732193, No Iterations 6
time step continuity errors : sum local = 4.29802e-07, global = 1.57268e-20, cumulative = 5.95866e-18
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.00012387
GAMG:  Solving for p, Initial residual = 0.0810305, Final residual = 0.00054485, No Iterations 6
time step continuity errors : sum local = 3.22957e-07, global = 2.11478e-20, cumulative = 5.97981e-18
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.000120508
GAMG:  Solving for p, Initial residual = 0.0189583, Final residual = 8.97181e-07, No Iterations 38
time step continuity errors : sum local = 5.24979e-10, global = 2.66036e-20, cumulative = 6.00642e-18
Pressure gradient source: uncorrected Ubar = 0.1335, pressure gradient = 0.00011971
ExecutionTime = 170.82 s  ClockTime = 171 s

End

kennyadapter

CPU型号：E5-2699 v4
系统：linux
OpenFOAM版本：OpenFOAM-1906
44 173.99
32 170.82
16 193.78
8 194.74
4 313.11
2 585.66
1 1146.46

为什么我的44核心会更慢呢，东岳老师？我最近在算一个200w网格的overset算例，算了半个多月了，算的还是很慢，有什么更好的解决方法吗？@东岳

kennyadapter

@netbuger 在clip中clip type选择scalar然后在下面选择CELLtype，，调整为1就行

kennyadapter

@VamosZhi 如果是2D的话是要extrudemesh一下，不过要注意下方向和起始面。我一开始也遇到过这个问题，试着改一下

flipNormals true;

这个参数，这个跟方向有关系，如果不行

sourcePatches (front);
exposedPatchName Back;

尝试改一下这两个，，换一下顺序

kennyadapter

各位老师们好，我最近使用OpenFOAM做楔形自由落体入水，OpenFOAM版本是 1906。我通过修改overInterDyMFoam例子中floatingBody案例将一个方块自由落体进入水中，发现可以计算，然后我将方块通过snappyHexMesh换为楔形，发现在计算到一半就发散了。
发散前后的速度场如图所示：

与论文的速度对比图：
我尝试使用blockMesh自己画楔形结果也是在某一处发散。
两个楔形网格如图所示：


motionSolverLibs    ("libsixDoFRigidBodyMotion.so");

dynamicFvMesh       dynamicOversetFvMesh;

solver          sixDoFRigidBodyMotion;

sixDoFRigidBodyMotionCoeffs
{

    patches         (floatingObject);
    innerDistance   100.0;
    outerDistance   101.0;

    centreOfMass    (3 1.5 1.2);
	momentOfInertia (40 921 921);

    // Density of the solid
    rhoSolid        466.7;

    // Cuboid mass
    mass           94.08;

velocity (0 0 -6.5788);
    report          on;
    accelerationRelaxation 0.6;
    accelerationDamping    0.9;

    solver
    {
        type Newmark;
    }

    constraints
    {

        /*
        fixedPoint
        {
             sixDoFRigidBodyMotionConstraint point;
             centreOfRotation (0.5 0.45 0.1);
        }
       */

        fixedLine
        {
            sixDoFRigidBodyMotionConstraint line;
            //centreOfRotation (0.5 0.45 0.1);
            direction (0 0 1);
        }
         fixedorentation
         {
            sixDoFRigidBodyMotionConstraint orientation;
             centreOfRotation (0.5 0.45 0.1);
         }
/*
        fixedAxis
        {
            sixDoFRigidBodyMotionConstraint axis;
            axis (0 1 0);
        }
        */
    }
}

这是我动网格的代码，也尝试改过

accelerationRelaxation

数值，但是效果也不明显，希望各位老师给出一些建议，非常感谢！

kennyadapter

@wwzhao 谢谢您的回复！

kennyadapter

@wwzhao 老师方便的话能加一下QQ讨论么，我的QQ号码：1219854212，非常感谢您

kennyadapter

@kennyadapter

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