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@李东岳 driftFluxFoam可以捕捉自由液面吗

自己来回复下，可以在cfd-post中，location->iso-clip，选择分组后通过坐标或其他参数的限定来找到对应面

但计算过程中会出现CFL数突然增大之后报错的问题Mean and max Courant Numbers = 0.0196702 0.2
deltaT = 1.34917e-09
Time = 1.381229231e-07

diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
DILUPBiCG: Solving for N2, Initial residual = 0.102714, Final residual = 8.31435e-10, No Iterations 11
DILUPBiCG: Solving for O2, Initial residual = 0.0998228, Final residual = 2.97854e-08, No Iterations 11
DILUPBiCG: Solving for NO, Initial residual = 0.00103043, Final residual = 4.54498e-07, No Iterations 11
DILUPBiCG: Solving for N2+, Initial residual = 0.157236, Final residual = 1.27729e-09, No Iterations 11
DILUPBiCG: Solving for O2+, Initial residual = 0.157241, Final residual = 1.44374e-09, No Iterations 11
DILUPBiCG: Solving for NO+, Initial residual = 0.157279, Final residual = 1.20494e-09, No Iterations 11
DILUPBiCG: Solving for N, Initial residual = 0.00643012, Final residual = 4.19377e-07, No Iterations 11
DILUPBiCG: Solving for O, Initial residual = 0.00193657, Final residual = 2.2919e-07, No Iterations 11
DILUPBiCG: Solving for N+, Initial residual = 0.157174, Final residual = 1.12526e-09, No Iterations 11
DILUPBiCG: Solving for O+, Initial residual = 0.156703, Final residual = 1.23372e-08, No Iterations 11
DILUPBiCG: Solving for e-, Initial residual = 0.0591289, Final residual = 2.85246e-15, No Iterations 5
diagonal: Solving for rhoUx, Initial residual = 0, Final residual = 0, No Iterations 0
diagonal: Solving for rhoUy, Initial residual = 0, Final residual = 0, No Iterations 0
diagonal: Solving for rhoUz, Initial residual = 0, Final residual = 0, No Iterations 0
smoothSolver: Solving for Ux, Initial residual = 5.41102e-05, Final residual = 5.24963e-09, No Iterations 120
smoothSolver: Solving for Uy, Initial residual = 0.00128686, Final residual = 1.27448e-07, No Iterations 160
smoothSolver: Solving for Uz, Initial residual = 0.000139985, Final residual = 1.28962e-08, No Iterations 70
diagonal: Solving for rhoEv, Initial residual = 0, Final residual = 0, No Iterations 0
diagonal: Solving for rhoE, Initial residual = 0, Final residual = 0, No Iterations 0
smoothSolver: Solving for hevel, Initial residual = 0.000257938, Final residual = 3.98118e-07, No Iterations 400
smoothSolver: Solving for e, Initial residual = 0.00686842, Final residual = 6.70799e-06, No Iterations 140
Attempt to use rho2ReactionThermo out of temperature range 139 times during this iteration.
 Thigh: 40000 < 640000
Phase no 1.0 ExecutionTime = 4.97 s ClockTime = 5 s Iteration no 112 (0.04 s)

Mean and max Courant Numbers = 0.0196515 0.552368
deltaT = 4.88502e-10
Time = 1.386114254e-07

diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
DILUPBiCG: Solving for N2, Initial residual = 0.0831271, Final residual = 4.94891e-09, No Iterations 11
DILUPBiCG: Solving for O2, Initial residual = 0.0830444, Final residual = 6.0302e-09, No Iterations 11
DILUPBiCG: Solving for NO, Initial residual = 0.0225179, Final residual = 4.10796e-07, No Iterations 11
DILUPBiCG: Solving for N2+, Initial residual = 0.070932, Final residual = 1.23497e-08, No Iterations 11
DILUPBiCG: Solving for O2+, Initial residual = 0.0707959, Final residual = 1.16027e-08, No Iterations 11
DILUPBiCG: Solving for NO+, Initial residual = 0.0712528, Final residual = 1.38649e-08, No Iterations 11
DILUPBiCG: Solving for N, Initial residual = 0.117227, Final residual = 8.58776e-08, No Iterations 11
DILUPBiCG: Solving for O, Initial residual = 0.209694, Final residual = 8.63459e-07, No Iterations 11
DILUPBiCG: Solving for N+, Initial residual = 0.240723, Final residual = 1.5458e-05, No Iterations 11
DILUPBiCG: Solving for O+, Initial residual = 0.0709349, Final residual = 3.14266e-08, No Iterations 11
DILUPBiCG: Solving for e-, Initial residual = 0.0330941, Final residual = 7.94061e-14, No Iterations 3
diagonal: Solving for rhoUx, Initial residual = 0, Final residual = 0, No Iterations 0
diagonal: Solving for rhoUy, Initial residual = 0, Final residual = 0, No Iterations 0
diagonal: Solving for rhoUz, Initial residual = 0, Final residual = 0, No Iterations 0
smoothSolver: Solving for Ux, Initial residual = 1.89119e-05, Final residual = 1.65027e-09, No Iterations 70
smoothSolver: Solving for Uy, Initial residual = 0.000264353, Final residual = 2.41377e-08, No Iterations 102
smoothSolver: Solving for Uz, Initial residual = 5.29899e-05, Final residual = 5.01779e-09, No Iterations 70
diagonal: Solving for rhoEv, Initial residual = 0, Final residual = 0, No Iterations 0
diagonal: Solving for rhoE, Initial residual = 0, Final residual = 0, No Iterations 0
smoothSolver: Solving for hevel, Initial residual = 0.278772, Final residual = 249.287, No Iterations 400
smoothSolver: Solving for e, Initial residual = 0.00510102, Final residual = 1.56626e+32, No Iterations 400
Attempt to use rho2ReactionThermo out of temperature range 3106 times during this iteration.
-2.31822e+10 < Tlow: 200
 Thigh: 40000 < 3.66402e+10
Phase no 1.0 ExecutionTime = 5.02 s ClockTime = 5 s Iteration no 113 (0.05 s)

[10] #0 Foam::error::printStack(Foam::Ostream&)[9] #0 Foam::error::printStack(Foam::Ostream&) at ??:?
at ??:?
[9] #1 Foam::sigFpe::sigHandler(int)[10] #1 Foam::sigFpe::sigHandler(int) at ??:?
[9] #2 ? at ??:?
[10] #2 ? in "/lib/x86_64-linux-gnu/libc.so.6"
[9] #3 Foam::sqrt(Foam::Field<double>&, Foam::UList<double> const&) in "/lib/x86_64-linux-gnu/libc.so.6"
[10] #3 Foam::sqrt(Foam::Field<double>&, Foam::UList<double> const&) at ??:?
[9] #4 Foam::tmp<Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> > Foam::sqrt<Foam::fvPatchField, Foam::volMesh>(Foam::tmp<Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> > const&) in "/home/sy/OpenFOAM/sy-v1706/platforms/linux64GccDPInt32Opt/bin/hy2Foam"
[9] #5 at ??:?
[10] #4 ?Foam::tmp<Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> > Foam::sqrt<Foam::fvPatchField, Foam::volMesh>(Foam::tmp<Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> > const&) in "/home/sy/OpenFOAM/sy-v1706/platforms/linux64GccDPInt32Opt/bin/hy2Foam"
[9] #6 in "/home/sy/OpenFOAM/sy-v1706/platforms/linux64GccDPInt32Opt/bin/hy2Foam"
[10] #5 ?? in "/home/sy/OpenFOAM/sy-v1706/platforms/linux64GccDPInt32Opt/bin/hy2Foam"
[9] #7 __libc_start_main in "/home/sy/OpenFOAM/sy-v1706/platforms/linux64GccDPInt32Opt/bin/hy2Foam"
[10] #6 in "/lib/x86_64-linux-gnu/libc.so.6"
[9] #8 ?? in "/home/sy/OpenFOAM/sy-v1706/platforms/linux64GccDPInt32Opt/bin/hy2Foam"
[10] #7 __libc_start_main in "/home/sy/OpenFOAM/sy-v1706/platforms/linux64GccDPInt32Opt/bin/hy2Foam"
[DESKTOP-N36BFE3:23240] *** Process received signal ***
[DESKTOP-N36BFE3:23240] Signal: Floating point exception (8)
[DESKTOP-N36BFE3:23240] Signal code: (-6)
[DESKTOP-N36BFE3:23240] Failing at address: 0x3e800005ac8
[DESKTOP-N36BFE3:23240] [ 0] /lib/x86_64-linux-gnu/libc.so.6(+0x43090)[0x7f49b1370090]
[DESKTOP-N36BFE3:23240] [ 1] /lib/x86_64-linux-gnu/libc.so.6(gsignal+0xcb)[0x7f49b137000b]
[DESKTOP-N36BFE3:23240] [ 2] in "/lib/x86_64-linux-gnu/libc./lib/x86_64-linux-gnu/libc.so.6(+0x43090)[0x7f49b1370090]
[DESKTOP-N36BFE3:23240] [ 3] so.6"
[10] #8 /home/sy/OpenFOAM/OpenFOAM-v1706/platforms/linux64GccDPInt32Opt/lib/libOpenFOAM.so(_ZN4Foam4sqrtERNS_5FieldIdEERKNS_5UListIdEE+0x3a)[0x7f49b1f24b7a]
[DESKTOP-N36BFE3:23240] [ 4] hy2Foam(ZN4Foam4sqrtINS_12fvPatchFieldENS_7volMeshEEENS_3tmpINS_14GeometricFieldIdT_T0_EEEERKS8+0x174)[0x55dafcc83f74]
[DESKTOP-N36BFE3:23240] [ 5] hy2Foam(+0x3fed5)[0x55dafcc10ed5]
[DESKTOP-N36BFE3:23240] [ 6] hy2Foam(+0x3464c)[0x55dafcc0564c]
[DESKTOP-N36BFE3:23240] [ 7] /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf3)[0x7f49b1351083]
[DESKTOP-N36BFE3:23240] [ 8] hy2Foam(+0x35f1e)[0x55dafcc06f1e]
[DESKTOP-N36BFE3:23240] *** End of error message ***
? in "/home/sy/OpenFOAM/sy-v1706/platforms/linux64GccDPInt32Opt/bin/hy2Foam"
[DESKTOP-N36BFE3:23241] *** Process received signal ***
[DESKTOP-N36BFE3:23241] Signal: Floating point exception (8)
[DESKTOP-N36BFE3:23241] Signal code: (-6)
[DESKTOP-N36BFE3:23241] Failing at address: 0x3e800005ac9
[DESKTOP-N36BFE3:23241] [ 0] /lib/x86_64-linux-gnu/libc.so.6(+0x43090)[0x7fb8d8d28090]
[DESKTOP-N36BFE3:23241] [ 1] /lib/x86_64-linux-gnu/libc.so.6(gsignal+0xcb)[0x7fb8d8d2800b]
[DESKTOP-N36BFE3:23241] [ 2] /lib/x86_64-linux-gnu/libc.so.6(+0x43090)[0x7fb8d8d28090]
[DESKTOP-N36BFE3:23241] [ 3] /home/sy/OpenFOAM/OpenFOAM-v1706/platforms/linux64GccDPInt32Opt/lib/libOpenFOAM.so(_ZN4Foam4sqrtERNS_5FieldIdEERKNS_5UListIdEE+0x3a)[0x7fb8d98dcb7a]
[DESKTOP-N36BFE3:23241] [ 4] hy2Foam(ZN4Foam4sqrtINS_12fvPatchFieldENS_7volMeshEEENS_3tmpINS_14GeometricFieldIdT_T0_EEEERKS8+0x174)[0x55f634616f74]
[DESKTOP-N36BFE3:23241] [ 5] hy2Foam(+0x3fed5)[0x55f6345a3ed5]
[DESKTOP-N36BFE3:23241] [ 6] hy2Foam(+0x3464c)[0x55f63459864c]
[DESKTOP-N36BFE3:23241] [ 7] /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf3)[0x7fb8d8d09083]
[DESKTOP-N36BFE3:23241] [ 8] hy2Foam(+0x35f1e)[0x55f634599f1e]
[DESKTOP-N36BFE3:23241] *** End of error message *** Primary job terminated normally, but 1 process returned
a non-zero exit code. Per user-direction, the job has been aborted. mpirun noticed that process rank 9 with PID 0 on node DESKTOP-N36BFE3 exited on signal 8 (Floating point exception).

@hhj0219 您好，请问你用fluent算完LES后，怎么分析时均特征的？ 导入tecplot吗？（如何导入呢，要把不同时刻的dat文件导入吗？ 这样操作方便吗？感觉一下导入成千上万个dat，有点不敢想象）
还是使用自带的sampling，自带的sampling编辑一些公式很不方便

希望能交流下！谢谢

@leaon 后来这部分气泡溃灭工作做的怎样了

@ansel 你要是搁心里翻译成“小笨蛋”是不是就和大佬打情骂俏了:quwan:

:143:

来 irc ……
freenode 节点上有个 OpenFOAM 的非官方频道。

最大的缺点就是不在线时的信息，上线了也收不到。除非使用付费第三方。
优点就是使用门槛太高以至于没有墙的必要，可以说是没梯子情况下的世界之窗。
注册配置比较麻烦但可以跳过。

日常会有几个人闲聊

Screenshot from 2020-11-28 16-34-15.png

每个人都可以新建频道，频道就像个群组。

@biaowai 补充下，在Fluent理论和用户手册中搜索下，确实没有提到Picard，但出现了很多关于Newton-iteration的介绍，可能是Fluent更快收敛的一个原因

请问各位前辈，有没有界面蒸发源项的模型啊，找了好多都是壁面成核的，因为要做的工况是在气液界面处产生相变，而不是壁面加热导致相变的，看了一些文章好像找到没有one-group下界面蒸发的模型:136:

@yuhxFoamer
不是老师哈，我最近也在做网格验证，所以可以一起讨论下。
1.最小网格尺寸看起来变化了，网格的质量好像也不一致，看起来不是结构网格。要考虑设置相同的计算参数。
2.几何尺寸发生变化会导致雷诺数、参考面积这些的变化。我看你的计算域在三个方向上都发生了改变，检查一下基于这些几何参数的其他量是不是也相对需要改动。

你可以按照这个方案来检查，首先在原本能够顺利计算的网格上直接加密，看看是否发散。然后使用缩放命令改变网格（不再加密）transformPoints -scale "( 2 2 1)"，设置对应尺寸下的物理参数计算验证。一般来说没有很密的边界层的话可以这样调整，这样不行的话就进一步考虑离散方法和数值精度的调整，先用一阶的，再反复调整这样。

@biaowai 并不是，它每次发布都重新上传😓，没搞懂他们的操作

对于URANS，多了个瞬态项，那每个时间步计算的时均速度（时均动量）都是从第一个时间步开始累加后平均后获得么？

对于$\int_t^{t+\Delta t}$的$\Delta t$，从理论上URANS这个$\Delta t$是任意的，如果不考虑附加的湍流封闭模型如ke之类，$\Delta t$足够的小，就变成了LES，$\Delta t$足够的大，就变成了RANS。然而$\Delta t$并不需要显性的给定。所以对URANS取决定性的还是$\mu_t$

多面体明显质量好过关 过基础计算关 相对正六面体 同样参数控制 数量变小了

他这个聊天记录我没太懂。什么是拖布结构？

我已经找到原因了，是因为材料粘度引起的沿程损失低于重力引起位压时就会出现这种出口比进口压力大的现象。

最近看到一种说法，level set方程是简化版的相场方程，结合这三种方法在方程形式上非常相似，不知道从计算精度、计算量等方面来讲，这三个方法的优缺点有没有什么对比性结论？

这只要不在里面，就是界面上面产生的相变，那就是相含率不为零的地方，相界面不平，首先一个原因是网格，另一个原因就是蒸发过程中不是瞬间变成小密度水蒸气，而是逐渐变小的。

@西湖冷月 对的，这里说硬盘已经是默认是移动硬盘了，移动硬盘就当个大u盘了，拔插就关机太费劲了…