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@zbxia 压力场不收敛的原因很难找，首先，我是个菜鸡，深层次的原因我没找到，只能说有些增加稳定性的大致方向，通过大量的试错来解决。其次，对于你的问题，只看你的描述我没有什么思路，只能建议你把网格质量在检查一下，因为snappyHexMesh的网格有时候其实不那么理想。

此问题已解决，影响最大的因素已经找出，感觉就是压力场求解问题，增大PIMPLE外循环次数就正常了。。。

附上两个时间步的输出日志，大佬们看看，能不能给点建议，谢谢大佬。

Courant Number mean: 0.00735537390793 max: 0.583636577736
Interface Courant Number mean: 0.000511181990626 max: 0.583636577736
deltaT = 0.000244897959184
Time = 0.0140204

PIMPLE: iteration 1
forces forces:
    rho: rho
    Not including porosity effects

6-DoF rigid body motion
    Centre of rotation: (-8.94498440699e-07 -0.0164456747667 0)
    Centre of mass: (-8.94498440699e-07 -0.0164456747667 0)
    Orientation: (0.999999999848 -1.74335290174e-05 0 1.74335290174e-05 0.999999999848 0 0 0 1)
    Linear velocity: (-0.00293368624098 -48.7266053369 0)
    Angular velocity: (0 0 0.0260211371501)
cellVolumeWeight : detected 2 mesh regions

    zone:0 nCells:15232
    zone:1 nCells:1408
Marking patch-cells on zone 0
Marking patch-cells on zone 1

After patch analysis : nCells : 16640
    other  : 15832
    patch  : 604
    overset: 204

Creating mesh-to-mesh addressing for region0 and region0 regions using cellVolumeWeight
meshToMesh: Using AABBTree method
    Overlap volume: 0.00109999996229
cellVolumeWeight : detected 3 mesh regions after overset

Front : fraction:1 size:364
Overset analysis : nCells : 16640
    calculated   : 15551
    interpolated : 356
    hole         : 733

Updating StokesII wave model for patch inlet
Updating shallowWaterAbsorption wave model for patch outlet
Execution time for mesh.update() = 0.13 s
Updating StokesII wave model for patch inlet
smoothSolver:  Solving for alpha.water, Initial residual = 0.000249999048227, Final residual = 6.80498898311e-11, No Iterations 3
Phase-1 volume fraction = 0.503920613005  Min(alpha.water) = -5.13127170995e-12  Max(alpha.water) = 1
MULES: Correcting alpha.water
MULES: Correcting alpha.water
MULES: Correcting alpha.water
Phase-1 volume fraction = 0.50392714434  Min(alpha.water) = -6.63435707652e-05  Max(alpha.water) = 1.0000000001
Updating StokesII wave model for patch inlet
smoothSolver:  Solving for alpha.water, Initial residual = 0.000249103932209, Final residual = 6.43573158857e-11, No Iterations 3
Phase-1 volume fraction = 0.504175477931  Min(alpha.water) = -2.94680004953e-12  Max(alpha.water) = 1
MULES: Correcting alpha.water
MULES: Correcting alpha.water
MULES: Correcting alpha.water
Phase-1 volume fraction = 0.504183786184  Min(alpha.water) = -0.00017940434073  Max(alpha.water) = 1
Updating StokesII wave model for patch inlet
DILUPBiCGStab:  Solving for p_rgh, Initial residual = 0.000310868744296, Final residual = 3.04422030153e-06, No Iterations 58
time step continuity errors : sum local = 3.96490246774e-05, global = -1.25171001239e-05, cumulative = -1.49775393475e-05
DILUPBiCGStab:  Solving for p_rgh, Initial residual = 1.34902179705e-05, Final residual = 7.69997478103e-10, No Iterations 94
time step continuity errors : sum local = 3.38122940616e-07, global = -3.37601268199e-07, cumulative = -1.53151406157e-05
PIMPLE: iteration 2
Updating StokesII wave model for patch inlet
smoothSolver:  Solving for alpha.water, Initial residual = 0.00120237279896, Final residual = 3.53930819687e-09, No Iterations 4
Phase-1 volume fraction = 0.504912181473  Min(alpha.water) = 0  Max(alpha.water) = 1
MULES: Correcting alpha.water
MULES: Correcting alpha.water
MULES: Correcting alpha.water
Phase-1 volume fraction = 0.504919520521  Min(alpha.water) = -3.14841185265e-05  Max(alpha.water) = 1.00000029283
Updating StokesII wave model for patch inlet
smoothSolver:  Solving for alpha.water, Initial residual = 0.00119880798848, Final residual = 6.98825518494e-09, No Iterations 4
Phase-1 volume fraction = 0.506154056117  Min(alpha.water) = 0  Max(alpha.water) = 1.00000002043
MULES: Correcting alpha.water
MULES: Correcting alpha.water
MULES: Correcting alpha.water
Phase-1 volume fraction = 0.506165779936  Min(alpha.water) = -1.68626784389e-05  Max(alpha.water) = 1.00000005014
Updating StokesII wave model for patch inlet
DILUPBiCGStab:  Solving for p_rgh, Initial residual = 1.90517587839e-05, Final residual = 1.8214651533e-07, No Iterations 37
time step continuity errors : sum local = 4.1923654332e-05, global = -3.05018962765e-05, cumulative = -4.58170368922e-05
DILUPBiCGStab:  Solving for p_rgh, Initial residual = 6.39065412577e-06, Final residual = 7.63397439793e-10, No Iterations 75
time step continuity errors : sum local = 1.86237192469e-07, global = -1.31816202546e-07, cumulative = -4.59488530947e-05
ExecutionTime = 8.5 s  ClockTime = 12 s

Courant Number mean: 0.235814158846 max: 5.37427555926
Interface Courant Number mean: 0.00949195777417 max: 2.51708515605
deltaT = 6.9970845481e-05
Time = 0.0140904

PIMPLE: iteration 1
forces forces:
    rho: rho
    Not including porosity effects

6-DoF rigid body motion
    Centre of rotation: (-1.08067779962e-06 -0.019295752321 0)
    Centre of mass: (-1.08067779962e-06 -0.019295752321 0)
    Orientation: (0.999999999816 -1.92012124244e-05 0 1.92012124244e-05 0.999999999816 0 0 0 1)
    Linear velocity: (-0.00238794043494 -32.7381114221 0)
    Angular velocity: (0 0 0.0245051469086)
cellVolumeWeight : detected 2 mesh regions

    zone:0 nCells:15232
    zone:1 nCells:1408
Marking patch-cells on zone 0
Marking patch-cells on zone 1

After patch analysis : nCells : 16640
    other  : 15832
    patch  : 604
    overset: 204

Creating mesh-to-mesh addressing for region0 and region0 regions using cellVolumeWeight
meshToMesh: Using AABBTree method
    Overlap volume: 0.00109999999488
cellVolumeWeight : detected 3 mesh regions after overset

Front : fraction:1 size:364
Overset analysis : nCells : 16640
    calculated   : 15551
    interpolated : 356
    hole         : 733

Updating StokesII wave model for patch inlet
Updating shallowWaterAbsorption wave model for patch outlet
Execution time for mesh.update() = 0.14 s
Updating StokesII wave model for patch inlet
smoothSolver:  Solving for alpha.water, Initial residual = 0.000377707391121, Final residual = 6.71971274391e-09, No Iterations 2
Phase-1 volume fraction = 0.506638642972  Min(alpha.water) = -6.04435695918e-08  Max(alpha.water) = 1.00000001498
MULES: Correcting alpha.water
MULES: Correcting alpha.water
MULES: Correcting alpha.water
Phase-1 volume fraction = 0.506641278027  Min(alpha.water) = -6.02169762921e-08  Max(alpha.water) = 1.00000001498
Updating StokesII wave model for patch inlet
smoothSolver:  Solving for alpha.water, Initial residual = 0.000377799740649, Final residual = 6.97823487912e-09, No Iterations 2
Phase-1 volume fraction = 0.507013009003  Min(alpha.water) = -2.53184572837e-09  Max(alpha.water) = 1.00000000834
MULES: Correcting alpha.water
MULES: Correcting alpha.water
MULES: Correcting alpha.water
Phase-1 volume fraction = 0.507014571193  Min(alpha.water) = -2.4774186131e-09  Max(alpha.water) = 1.00000000834
Updating StokesII wave model for patch inlet
DILUPBiCGStab:  Solving for p_rgh, Initial residual = 5.44491503205e-05, Final residual = 1.57391889401e-07, No Iterations 54
time step continuity errors : sum local = 2.51380621235e-06, global = 4.18779084622e-08, cumulative = -4.59069751863e-05
DILUPBiCGStab:  Solving for p_rgh, Initial residual = 1.4141816622e-05, Final residual = 6.93894196946e-10, No Iterations 95
time step continuity errors : sum local = 1.92459691085e-08, global = 2.85638433789e-09, cumulative = -4.59041188019e-05
PIMPLE: iteration 2
Updating StokesII wave model for patch inlet
smoothSolver:  Solving for alpha.water, Initial residual = 0.000607091902099, Final residual = 1.08827165501e-10, No Iterations 3
Phase-1 volume fraction = 0.506766015426  Min(alpha.water) = -3.06640979772e-09  Max(alpha.water) = 1.00000000775
MULES: Correcting alpha.water
MULES: Correcting alpha.water
MULES: Correcting alpha.water
Phase-1 volume fraction = 0.506769027235  Min(alpha.water) = -2.9938628057e-09  Max(alpha.water) = 1.00000000775
Updating StokesII wave model for patch inlet
smoothSolver:  Solving for alpha.water, Initial residual = 0.000498218264715, Final residual = 9.8336652446e-09, No Iterations 2
Phase-1 volume fraction = 0.507267924831  Min(alpha.water) = -7.65421127887e-10  Max(alpha.water) = 1.00000000487
MULES: Correcting alpha.water
MULES: Correcting alpha.water
MULES: Correcting alpha.water
Phase-1 volume fraction = 0.507269775942  Min(alpha.water) = -7.50043599137e-10  Max(alpha.water) = 1.00000000486
Updating StokesII wave model for patch inlet
DILUPBiCGStab:  Solving for p_rgh, Initial residual = 9.0967455725e-06, Final residual = 8.77703691491e-08, No Iterations 28
time step continuity errors : sum local = 2.08615978654e-06, global = 1.47998645536e-06, cumulative = -4.44241323466e-05
DILUPBiCGStab:  Solving for p_rgh, Initial residual = 1.37725643056e-06, Final residual = 9.51675297182e-10, No Iterations 65
time step continuity errors : sum local = 2.26526056154e-08, global = 1.96253692104e-09, cumulative = -4.44221698096e-05
ExecutionTime = 8.78 s  ClockTime = 13 s

对浮体区域进行了加密，感觉网格已经足够细了，而且是一个方箱，网格应该没问题了，但是仍然还是算不了😑，仔细研究了一下log文件，感觉压强场发散了，可是我还是找不到是那里的问题。。。

本身是一个很简单的案例，二维的方箱在波浪作用下运动，使用了重叠网格，用of自带的floatingBody案例更改的，可是在计算了几步后，方箱的垂向速度振荡，最后慢慢变大，到了18次方的量级，用命令提取了部分方箱的线速度如下：

    Linear velocity: (-1.91542457151e-06 -0.00135827305279 0)
    Linear velocity: (-2.15710332077e-06 0.00111202047891 0)
    Linear velocity: (-2.41767412947e-06 0.00260261966864 0)
    ....
    Linear velocity: (0.0989209598413 -546.73550894 0)
    Linear velocity: (0.0883712548553 -340.476075085 0)
    Linear velocity: (0.0467607474571 185.838921431 -0)
    Linear velocity: (0.150364701271 -361.987863494 0)
    Linear velocity: (0.359492211159 -1874.79348536 0)
    Linear velocity: (0.318758482597 -1159.16674178 0)
    Linear velocity: (0.192438074537 630.147173239 -0)
    Linear velocity: (0.680108763246 -1456.15159395 0)
    Linear velocity: (1.49788128146 -6826.0000562 0)
    Linear velocity: (1.41386364482 -4264.12384652 0)
    Linear velocity: (0.956295248336 2153.26695027 0)
    Linear velocity: (2.51485988514 -5514.66212084 0)
    Linear velocity: (4.96732483128 -24310.1703926 0)
    Linear velocity: (4.44524314882 -14419.2509978 0)
    Linear velocity: (2.44194802246 9150.62467989 -0)
    Linear velocity: (9.1294805619 -23302.6849784 0)
    Linear velocity: (20.4668906787 -93213.9366717 0)
    Linear velocity: (19.8687629901 -55798.9112031 0)
    Linear velocity: (15.9451318073 32453.0741479 -0)
    Linear velocity: (42.6515469395 -100098.024999 0)
    Linear velocity: (80.7624597507 -357186.307128 0)
    Linear velocity: (74.8730279424 -202941.440388 0)
    Linear velocity: (40.1654968732 138596.03469 -0)
    Linear velocity: (152.128923734 -409740.496391 0)
    Linear velocity: (306.976847121 -1346764.10283 0)
   ...
    Linear velocity: (461955.202831 -941127581.331 0)
    Linear velocity: (1454171.11916 -4517414949.32 0)
    Linear velocity: (30500257.004 -23096949614.6 0)
    Linear velocity: (-2711275695.75 -9.23445027755e+12 0)
    Linear velocity: (-182076601222 2.15967217623e+14 0)
    Linear velocity: (357016928793 3.37572779872e+14 0)
    Linear velocity: (-165982717722 1.87348726017e+14 0)
    Linear velocity: (-1.80226889532e+12 -8.18857537503e+13 0)
    Linear velocity: (1.9713735909e+12 1.46486850954e+14 0)
    Linear velocity: (1.03390418821e+13 7.76730469486e+14 0)
    Linear velocity: (1.35887023944e+12 5.06243915037e+14 -0)
    Linear velocity: (-1.61594169478e+13 -1.7900944247e+14 0)
    Linear velocity: (-8.51102456927e+12 1.89480548646e+13 0)

这时候后处理发现方箱早就飞出去了😂，我把能想到的地方都尝试了一遍，前后经过了三四天，结果还是不行，感觉已经黔驴技穷了，我把代码贴下面，希望哪位大佬能够指点一二，在下感激不尽。floatingBody.zip

大家好，请问这个问题解决了吗？我用overinerDyMFoam算一个二维方块浮体也遇到了这个问题，更改了很多参数都没解决。。。

@学流体的小明 我也觉得难搞，我重组了某个时间步的网格文件，发现只有一个point文件，可能要一个点一个点的加😫，而且还有各种场文件貌似也要改😂

@学流体的小明 感谢大佬的回复，这个重组网格我明白，但是如何更改某一时间步的网格我不知道怎么做。就比如已经分块计算了10s，我想在下一个时间步把背景网格的高度增加一点，这个想法能实现吗？

如题，在下刚入门openfoam，使用重叠网格算了一个比较复杂的算例，但在计算过程中发现起先设计的背景网格长度有些短了，但是已经算了很长时间，不想重新计算，前功尽弃😥，觉得可以在某一时间步调整一下网格。于是我想在中途调整一下网格，我的思路是从分块中重组最适合的时间步，然后对这一时间步进行网格调整，然后在将这一时间步重新分块再接着计算。但是最关键的网格调整，因为有重叠网格，那一时刻结构物的位置需要保留，而且重组后的时间步里的polyMesh里只有一个point文件，不知该如何调整，想请各位大佬指点一二，在下跪谢

@maoyanjun_dut 前辈你好，请问您现在还做这方面工作吗？我根据您文章的第二种思路，用v2206编译了一个overMultiphseInterDyMFoam，编译成功了，但是跑了一个算例有些问题，边界层混乱，如图
请问前辈知道为什么吗？

我也是报这个错，请问您解决了吗？😢