可压流计算发散，出现Negative Initial Temperature 问题如何处理？
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我对OpenFOAM的应用，主要针对跨声速气动（外流）问题。所以，近来主要对可压缩流求解器进行应用学习。
学习路线：根据tutorials中可压缩流求解器的算例，替换了polyMesh，并进行边界条件修改。
因为是外流，所以设置比较简单。基本上只有inlet、far、outlet、wall这几个，类型用freestream/fixedValue/zeroGradient这些。
情况：
由于没有找到外流的三维算例，我直接修改了rhoSimpleFoam的naca0012算例（湍流模型、边界条件都按原算例，没修改），计算现成的机翼网格。因为是对称外形所以加了symmetryPlane几何边界。结果，都是一 步就发散。一开始以为是symmetryPlane的问题。尝试多次都计算发散后，转而计算一些简单的三维模型：sphere、cube、auger等。
之后先按照icoFoam的算例，用icoFoam计算了这些模型。都成功计算了。于是又把这些简单模型怼进这些可压流求解器。目前全部发散。。。
目前尝试的rhoSimpleFoam计算三维算例中，在Δt=1e-11的情况下，都是一步就发散了。。
Q1：请问各位有没有现成的可压缩三维外流算例，分享我学习参考呀？
在rhoCentralFoam（30-100步）和rhoPimpleFoam求解中，均出现了Negative Initial Temperature的问题。查到的有一点点相关性的，只有在其他求解器中出现负温度并减小p的容许误差。。但是在rhoCentralFoam中无法应用。
计算中maxCo在10的-3到-1量级。 仍有一步或几步发散的情况。
rcf：
rpf：
添加限制器，经过尝试也是没用的。
Q：请问如何处理负温度呀？？？Q：另外问一下，这报错后的输出怎么分析呢？我很多行里的？？？问号，是输出乱码么？？
rsf边界设置完全参考tutorials中二维翼型komegaSST算例（$FOAM_TUTORIALS/compressible/rhoSimpleFoam/aerofoilNACA0012），只不过去掉了两个empty边界，并入了freestream组。thermoproperty为标准气体。
就是外边界用freestreamVelocity，freestreamPressure，inletOutlet温度。固面边界用noSlip，zeroGradient压强/温度。
这个边界条件设置应该没问题吧？rcf算例参考compressible/rhoCentralFoam/obliqueShock算例，对进出口、外边界和固面边界应用了基础边界条件，fixedValue/zeroGradient/noSlip等，原则上性质和上面rsf的一样。
其中离散格式，求解器，松弛因子等一律没有改动。。
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问题太多，还有个问题是residuals记录的残差中出现N/A是怎么回事呀？是write精度6太低了吗？
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rcf计算中出现负温度，观察残差变化是e的迭代残差越来越大。能量方程发散。。。不知道调什么参数可以控制。。。
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文件太大，传不上来。
截个图，有个球（wall），前（inlet）后（outlet）周围（far）——一组freestream。
就这么简单。。。
其他几个即把球换成cube/auger。。。其他一样。 -
可能的原因太多了，先检查boundary conditions，你可以把case上传来看一下。
假如试了不同的BCs, 还是有问题。可以先做一些简单尝试。
rhoC 在做高mach number时候，出现这个错误，可以尝试把第一步dt降低很多。
rhoS 可能和simple算法有关，你可以在fvOption里面加个限制温度的：limitTemperature { type limitTemperature; active true; limitTemperatureCoeffs { selectionMode all; Tmin 300; Tmax 400; } }感觉你的thermo设定可能也有问题，你可以把file放上来看看。
还有mesh，checkMesh结果怎么样？ -
@sibo 好的，不过验证下来，限制器是没用的，很迷。。
thermo是根据翼型算例里的，应该是标准气体。FoamFile { version 2.0; format ascii; class dictionary; location "constant"; object 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 1.82e-05; Pr 0.71; } }球文件压不到500k，我看看cube的，或者分开传一下。
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我在functions中添加了minMax函数，监视了全流场的问题，发现并没有出现负温度。
# Field minima and maxima # Time field min location(min) max location(max) 1.2e-07 T 2.696479e+02 (8.215994e-03 5.250372e-03 2.435636e-03) 4.495993e+02 (9.916511e-03 1.748913e-03 -5.809184e-05) 2.20464e-07 T 2.694329e+02 (8.215994e-03 5.250372e-03 2.435636e-03) 5.149109e+02 (9.916511e-03 1.748913e-03 -5.809184e-05) 3.19452e-07 T 2.686871e+02 (-4.566989e-03 -8.019550e-03 -3.996615e-03) 5.535878e+02 (9.916511e-03 1.748913e-03 -5.809184e-05) 4.09167e-07 T 2.671276e+02 (-4.566989e-03 -8.019550e-03 -3.996615e-03) 5.876730e+02 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 4.93006e-07 T 2.666568e+02 (-4.566989e-03 -8.019550e-03 -3.996615e-03) 6.216799e+02 (9.916511e-03 1.748913e-03 -5.809184e-05) 5.72842e-07 T 2.661139e+02 (1.893625e-03 -2.021107e-03 9.696002e-03) 6.627089e+02 (9.916511e-03 1.748913e-03 -5.809184e-05) 6.49727e-07 T 2.651325e+02 (1.893625e-03 -2.021107e-03 9.696002e-03) 7.059861e+02 (9.916511e-03 1.748913e-03 -5.809184e-05) 7.24235e-07 T 2.642410e+02 (1.893625e-03 -2.021107e-03 9.696002e-03) 7.499664e+02 (9.916511e-03 1.748913e-03 -5.809184e-05) 7.96689e-07 T 2.634214e+02 (1.893625e-03 -2.021107e-03 9.696002e-03) 7.918172e+02 (9.916511e-03 1.748913e-03 -5.809184e-05) 8.6744e-07 T 2.626692e+02 (1.893625e-03 -2.021107e-03 9.696002e-03) 8.301858e+02 (9.916511e-03 1.748913e-03 -5.809184e-05) 9.36681e-07 T 2.619985e+02 (1.893625e-03 -2.021107e-03 9.696002e-03) 8.650293e+02 (9.916511e-03 1.748913e-03 -5.809184e-05) 1.00439e-06 T 2.614332e+02 (1.893625e-03 -2.021107e-03 9.696002e-03) 8.981848e+02 (9.916511e-03 1.748913e-03 -5.809184e-05) 1.07061e-06 T 2.609977e+02 (1.893625e-03 -2.021107e-03 9.696002e-03) 9.314664e+02 (9.916511e-03 1.748913e-03 -5.809184e-05) 1.13543e-06 T 2.606904e+02 (1.893625e-03 -2.021107e-03 9.696002e-03) 9.654756e+02 (9.916511e-03 1.748913e-03 -5.809184e-05) 1.19901e-06 T 2.604919e+02 (1.893625e-03 -2.021107e-03 9.696002e-03) 9.995595e+02 (9.916511e-03 1.748913e-03 -5.809184e-05) 1.26153e-06 T 2.603746e+02 (1.893625e-03 -2.021107e-03 9.696002e-03) 1.032485e+03 (9.916511e-03 1.748913e-03 -5.809184e-05) 1.32317e-06 T 2.603055e+02 (1.893625e-03 -2.021107e-03 9.696002e-03) 1.063088e+03 (9.916511e-03 1.748913e-03 -5.809184e-05) 1.38406e-06 T 2.602539e+02 (1.893625e-03 -2.021107e-03 9.696002e-03) 1.090833e+03 (9.916511e-03 1.748913e-03 -5.809184e-05) 1.44424e-06 T 2.601999e+02 (1.893625e-03 -2.021107e-03 9.696002e-03) 1.115950e+03 (9.916511e-03 1.748913e-03 -5.809184e-05) 1.50377e-06 T 2.601390e+02 (1.893625e-03 -2.021107e-03 9.696002e-03) 1.146849e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 1.56264e-06 T 2.600686e+02 (1.893625e-03 -2.021107e-03 9.696002e-03) 1.184469e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 1.62088e-06 T 2.599937e+02 (1.893625e-03 -2.021107e-03 9.696002e-03) 1.223112e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 1.67851e-06 T 2.599313e+02 (1.893625e-03 -2.021107e-03 9.696002e-03) 1.262965e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 1.73554e-06 T 2.599109e+02 (1.893625e-03 -2.021107e-03 9.696002e-03) 1.304196e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 1.79202e-06 T 2.599541e+02 (1.893625e-03 -2.021107e-03 9.696002e-03) 1.346820e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 1.84798e-06 T 2.600679e+02 (1.893625e-03 -2.021107e-03 9.696002e-03) 1.390685e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 1.90342e-06 T 2.602450e+02 (1.893625e-03 -2.021107e-03 9.696002e-03) 1.435474e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 1.95831e-06 T 2.604679e+02 (1.893625e-03 -2.021107e-03 9.696002e-03) 1.480803e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 2.01266e-06 T 2.604930e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 1.526320e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 2.06651e-06 T 2.594643e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 1.571781e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 2.11988e-06 T 2.582964e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 1.617080e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 2.17283e-06 T 2.570010e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 1.662265e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 2.22544e-06 T 2.556032e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 1.707489e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 2.27762e-06 T 2.541266e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 1.752686e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 2.32941e-06 T 2.525931e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 1.797121e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 2.3808e-06 T 2.510305e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 1.840190e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 2.43172e-06 T 2.494642e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 1.881550e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 2.48221e-06 T 2.479078e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 1.921795e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 2.53229e-06 T 2.463724e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 1.961208e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 2.58197e-06 T 2.448671e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 1.999808e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 2.63126e-06 T 2.433945e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.037475e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 2.68016e-06 T 2.419388e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.074062e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 2.72869e-06 T 2.404851e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.109503e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 2.77683e-06 T 2.390233e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.143836e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 2.82461e-06 T 2.375487e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.177186e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 2.87201e-06 T 2.360618e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.209711e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 2.91903e-06 T 2.345656e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.241571e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 2.96567e-06 T 2.330655e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.272895e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 3.01194e-06 T 2.315676e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.303771e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 3.05785e-06 T 2.300780e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.334254e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 3.1034e-06 T 2.286014e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.364381e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 3.14862e-06 T 2.271408e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.394175e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 3.19349e-06 T 2.256986e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.423653e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 3.23803e-06 T 2.242881e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.452803e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 3.28223e-06 T 2.229222e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.481638e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 3.32611e-06 T 2.216107e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.510185e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 3.36968e-06 T 2.203596e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.538467e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 3.41296e-06 T 2.191721e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.566500e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 3.45594e-06 T 2.180492e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.594293e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 3.49864e-06 T 2.169918e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.621849e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 3.54106e-06 T 2.160029e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.649166e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 3.58321e-06 T 2.150895e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.676222e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 3.6251e-06 T 2.142638e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.703003e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 3.66673e-06 T 2.135495e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.729486e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 3.7081e-06 T 2.130327e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.755586e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 3.74922e-06 T 2.127382e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.781383e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 3.79009e-06 T 2.125651e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.806984e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 3.83071e-06 T 2.125015e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.832461e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 3.87005e-06 T 2.125518e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.857208e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 3.90524e-06 T 2.127180e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 2.879415e+03 (-1.000665e-02 -2.174274e-04 -1.385346e-03) 3.93612e-06 T 2.129961e+02 (7.378156e-03 -6.804851e-03 9.365358e-04) 7.343916e+03 (2.644925e-03 -9.205346e-05 -9.943070e-03)这个Negative Initial Temperature好像是最后一次迭代中对应initial residual出现的。。。
@sibo -
这是最后一步计算后出现的报错。
deltaT = 2.51006e-08 Mean and max Courant Numbers = 0.00325402 0.556524 Time = 3.96122e-06 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 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 = 7.83279e-08, Final residual = 2.39049e-06, No Iterations 1000 smoothSolver: Solving for Uy, Initial residual = 1.35404e-07, Final residual = 1.61978e-06, No Iterations 1000 smoothSolver: Solving for Uz, Initial residual = 1.24936e-07, Final residual = 1.71417e-06, No Iterations 1000 diagonal: Solving for rhoE, Initial residual = 0, Final residual = 0, No Iterations 0 smoothSolver: Solving for e, Initial residual = 1.26486e-08, Final residual = 1.47147e-05, No Iterations 1000 --> FOAM FATAL ERROR: Negative initial temperature T0: -26044 From function Foam::scalar Foam::species::thermo<Thermo, Type>::T(Foam::scalar, Foam::scalar, Foam::scalar, Foam::scalar (Foam::species::thermo<Thermo, Type>::*)(Foam::scalar, Foam::scalar) const, Foam::scalar (Foam::species::thermo<Thermo, Type>::*)(Foam::scalar, Foam::scalar) const, Foam::scalar (Foam::species::thermo<Thermo, Type>::*)(Foam::scalar) const, bool) const [with Thermo = Foam::hConstThermo<Foam::perfectGas<Foam::specie> >; Type = Foam::sensibleInternalEnergy; Foam::scalar = double; Foam::species::thermo<Thermo, Type> = Foam::species::thermo<Foam::hConstThermo<Foam::perfectGas<Foam::specie> >, Foam::sensibleInternalEnergy>] in file /home/rebel/OpenFOAM/OpenFOAM-7/src/thermophysicalModels/specie/lnInclude/thermoI.H at line 56. FOAM aborting #0 Foam::error::printStack(Foam::Ostream&) at ??:? #1 Foam::error::abort() at ??:? #2 Foam::species::thermo<Foam::hConstThermo<Foam::perfectGas<Foam::specie> >, Foam::sensibleInternalEnergy>::T(double, double, double, double (Foam::species::thermo<Foam::hConstThermo<Foam::perfectGas<Foam::specie> >, Foam::sensibleInternalEnergy>::*)(double, double) const, double (Foam::species::thermo<Foam::hConstThermo<Foam::perfectGas<Foam::specie> >, Foam::sensibleInternalEnergy>::*)(double, double) const, double (Foam::species::thermo<Foam::hConstThermo<Foam::perfectGas<Foam::specie> >, Foam::sensibleInternalEnergy>::*)(double) const, bool) const at ??:? #3 Foam::hePsiThermo<Foam::psiThermo, Foam::pureMixture<Foam::constTransport<Foam::species::thermo<Foam::hConstThermo<Foam::perfectGas<Foam::specie> >, Foam::sensibleInternalEnergy> > > >::calculate() at ??:? #4 Foam::hePsiThermo<Foam::psiThermo, Foam::pureMixture<Foam::constTransport<Foam::species::thermo<Foam::hConstThermo<Foam::perfectGas<Foam::specie> >, Foam::sensibleInternalEnergy> > > >::correct() at ??:? #5 ? in "/home/rebel/OpenFOAM/OpenFOAM-7/platforms/linux64GccDPInt32Opt/bin/rhoCentralFoam" #6 __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6" #7 ? in "/home/rebel/OpenFOAM/OpenFOAM-7/platforms/linux64GccDPInt32Opt/bin/rhoCentralFoam" -
残差监视，也没有过高量级的残差。。。
# Residuals # Time rho Ux Uy Uz rhoUx rhoUy rhoUz e rhoE 1.2e-07 0.000000e+00 9.999998e-01 9.999987e-01 9.999987e-01 0.000000e+00 0.000000e+00 0.000000e+00 7.969064e-06 0.000000e+00 2.20464e-07 0.000000e+00 2.111891e-06 1.380125e-05 4.022545e-06 0.000000e+00 0.000000e+00 0.000000e+00 1.313458e-07 0.000000e+00 3.19452e-07 0.000000e+00 1.264645e-06 1.060253e-05 3.560864e-06 0.000000e+00 0.000000e+00 0.000000e+00 1.072603e-07 0.000000e+00 4.09167e-07 0.000000e+00 8.909982e-07 7.791157e-06 3.130739e-06 0.000000e+00 0.000000e+00 0.000000e+00 8.653875e-08 0.000000e+00 4.93006e-07 0.000000e+00 6.980943e-07 6.014070e-06 2.919484e-06 0.000000e+00 0.000000e+00 0.000000e+00 7.321404e-08 0.000000e+00 5.72842e-07 0.000000e+00 5.830812e-07 4.767039e-06 2.802532e-06 0.000000e+00 0.000000e+00 0.000000e+00 6.407240e-08 0.000000e+00 6.49727e-07 0.000000e+00 5.076418e-07 3.877868e-06 2.757184e-06 0.000000e+00 0.000000e+00 0.000000e+00 5.741409e-08 0.000000e+00 7.24235e-07 0.000000e+00 4.533701e-07 3.258493e-06 2.747260e-06 0.000000e+00 0.000000e+00 0.000000e+00 5.230926e-08 0.000000e+00 7.96689e-07 0.000000e+00 4.120860e-07 2.797531e-06 2.719957e-06 0.000000e+00 0.000000e+00 0.000000e+00 4.823362e-08 0.000000e+00 8.6744e-07 0.000000e+00 3.798487e-07 2.445596e-06 2.661090e-06 0.000000e+00 0.000000e+00 0.000000e+00 4.496448e-08 0.000000e+00 9.36681e-07 0.000000e+00 3.528057e-07 2.173716e-06 2.574432e-06 0.000000e+00 0.000000e+00 0.000000e+00 4.225028e-08 0.000000e+00 1.00439e-06 0.000000e+00 3.283802e-07 1.954853e-06 2.469235e-06 0.000000e+00 0.000000e+00 0.000000e+00 3.986102e-08 0.000000e+00 1.07061e-06 0.000000e+00 3.059676e-07 1.783138e-06 2.365464e-06 0.000000e+00 0.000000e+00 0.000000e+00 3.775424e-08 0.000000e+00 1.13543e-06 0.000000e+00 2.856882e-07 1.649840e-06 2.271488e-06 0.000000e+00 0.000000e+00 0.000000e+00 3.591306e-08 0.000000e+00 1.19901e-06 0.000000e+00 2.679408e-07 1.542351e-06 2.183317e-06 0.000000e+00 0.000000e+00 0.000000e+00 3.432737e-08 0.000000e+00 1.26153e-06 0.000000e+00 2.527546e-07 1.454461e-06 2.101230e-06 0.000000e+00 0.000000e+00 0.000000e+00 3.297916e-08 0.000000e+00 1.32317e-06 0.000000e+00 2.397965e-07 1.381828e-06 2.032610e-06 0.000000e+00 0.000000e+00 0.000000e+00 3.182791e-08 0.000000e+00 1.38406e-06 0.000000e+00 2.287559e-07 1.318413e-06 1.970739e-06 0.000000e+00 0.000000e+00 0.000000e+00 3.082433e-08 0.000000e+00 1.44424e-06 0.000000e+00 2.191165e-07 1.260639e-06 1.915664e-06 0.000000e+00 0.000000e+00 0.000000e+00 2.992920e-08 0.000000e+00 1.50377e-06 0.000000e+00 2.106629e-07 1.207516e-06 1.863491e-06 0.000000e+00 0.000000e+00 0.000000e+00 2.911098e-08 0.000000e+00 1.56264e-06 0.000000e+00 2.031014e-07 1.158085e-06 1.805849e-06 0.000000e+00 0.000000e+00 0.000000e+00 2.835210e-08 0.000000e+00 1.62088e-06 0.000000e+00 1.962955e-07 1.112931e-06 1.741463e-06 0.000000e+00 0.000000e+00 0.000000e+00 2.764534e-08 0.000000e+00 1.67851e-06 0.000000e+00 1.900939e-07 1.072154e-06 1.669848e-06 0.000000e+00 0.000000e+00 0.000000e+00 2.698383e-08 0.000000e+00 1.73554e-06 0.000000e+00 1.844539e-07 1.034941e-06 1.592339e-06 0.000000e+00 0.000000e+00 0.000000e+00 2.636862e-08 0.000000e+00 1.79202e-06 0.000000e+00 1.793699e-07 1.000207e-06 1.511384e-06 0.000000e+00 0.000000e+00 0.000000e+00 2.580314e-08 0.000000e+00 1.84798e-06 0.000000e+00 1.747606e-07 9.661514e-07 1.428961e-06 0.000000e+00 0.000000e+00 0.000000e+00 2.527796e-08 0.000000e+00 1.90342e-06 0.000000e+00 1.704691e-07 9.317723e-07 1.346577e-06 0.000000e+00 0.000000e+00 0.000000e+00 2.477445e-08 0.000000e+00 1.95831e-06 0.000000e+00 1.664211e-07 8.963859e-07 1.267936e-06 0.000000e+00 0.000000e+00 0.000000e+00 2.428668e-08 0.000000e+00 2.01266e-06 0.000000e+00 1.626056e-07 8.606177e-07 1.194401e-06 0.000000e+00 0.000000e+00 0.000000e+00 2.382032e-08 0.000000e+00 2.06651e-06 0.000000e+00 1.590113e-07 8.257931e-07 1.128202e-06 0.000000e+00 0.000000e+00 0.000000e+00 2.338027e-08 0.000000e+00 2.11988e-06 0.000000e+00 1.556542e-07 7.923155e-07 1.069886e-06 0.000000e+00 0.000000e+00 0.000000e+00 2.297143e-08 0.000000e+00 2.17283e-06 0.000000e+00 1.525269e-07 7.609180e-07 1.017447e-06 0.000000e+00 0.000000e+00 0.000000e+00 2.259820e-08 0.000000e+00 2.22544e-06 0.000000e+00 1.496164e-07 7.324782e-07 9.736410e-07 0.000000e+00 0.000000e+00 0.000000e+00 2.226887e-08 0.000000e+00 2.27762e-06 0.000000e+00 1.465346e-07 7.066297e-07 9.352919e-07 0.000000e+00 0.000000e+00 0.000000e+00 2.191912e-08 0.000000e+00 2.32941e-06 0.000000e+00 1.434877e-07 6.848880e-07 8.998991e-07 0.000000e+00 0.000000e+00 0.000000e+00 2.158714e-08 0.000000e+00 2.3808e-06 0.000000e+00 1.405301e-07 6.660989e-07 8.692597e-07 0.000000e+00 0.000000e+00 0.000000e+00 2.126029e-08 0.000000e+00 2.43172e-06 0.000000e+00 1.375274e-07 6.494031e-07 8.415419e-07 0.000000e+00 0.000000e+00 0.000000e+00 2.091895e-08 0.000000e+00 2.48221e-06 0.000000e+00 1.347307e-07 6.358199e-07 8.170828e-07 0.000000e+00 0.000000e+00 0.000000e+00 2.059843e-08 0.000000e+00 2.53229e-06 0.000000e+00 1.321691e-07 6.252074e-07 7.936747e-07 0.000000e+00 0.000000e+00 0.000000e+00 2.029541e-08 0.000000e+00 2.58197e-06 0.000000e+00 1.297971e-07 6.172238e-07 7.706426e-07 0.000000e+00 0.000000e+00 0.000000e+00 2.000658e-08 0.000000e+00 2.63126e-06 0.000000e+00 1.275390e-07 6.113378e-07 7.484031e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.972816e-08 0.000000e+00 2.68016e-06 0.000000e+00 1.253656e-07 6.071383e-07 7.279950e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.945779e-08 0.000000e+00 2.72869e-06 0.000000e+00 1.232757e-07 6.040237e-07 7.093294e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.919438e-08 0.000000e+00 2.77683e-06 0.000000e+00 1.212711e-07 6.014336e-07 6.916158e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.893779e-08 0.000000e+00 2.82461e-06 0.000000e+00 1.193412e-07 5.995559e-07 6.748759e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.868760e-08 0.000000e+00 2.87201e-06 0.000000e+00 1.174162e-07 5.975158e-07 6.590531e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.843867e-08 0.000000e+00 2.91903e-06 0.000000e+00 1.155349e-07 5.954072e-07 6.447285e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.819406e-08 0.000000e+00 2.96567e-06 0.000000e+00 1.137252e-07 5.931181e-07 6.318952e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.795449e-08 0.000000e+00 3.01194e-06 0.000000e+00 1.120094e-07 5.904828e-07 6.202738e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.772064e-08 0.000000e+00 3.05785e-06 0.000000e+00 1.104089e-07 5.873203e-07 6.096358e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.749415e-08 0.000000e+00 3.1034e-06 0.000000e+00 1.089088e-07 5.834934e-07 5.999317e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.727551e-08 0.000000e+00 3.14862e-06 0.000000e+00 1.075045e-07 5.789331e-07 5.913303e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.706551e-08 0.000000e+00 3.19349e-06 0.000000e+00 1.061978e-07 5.736304e-07 5.838156e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.686157e-08 0.000000e+00 3.23803e-06 0.000000e+00 1.049280e-07 5.674663e-07 5.759674e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.665733e-08 0.000000e+00 3.28223e-06 0.000000e+00 1.037199e-07 5.610776e-07 5.664174e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.646217e-08 0.000000e+00 3.32611e-06 0.000000e+00 1.026262e-07 5.553960e-07 5.553930e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.627663e-08 0.000000e+00 3.36968e-06 0.000000e+00 1.015751e-07 5.504035e-07 5.461241e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.609845e-08 0.000000e+00 3.41296e-06 0.000000e+00 1.005783e-07 5.461918e-07 5.380770e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.592607e-08 0.000000e+00 3.45594e-06 0.000000e+00 9.962924e-08 5.417998e-07 5.316262e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.575875e-08 0.000000e+00 3.49864e-06 0.000000e+00 9.868994e-08 5.364300e-07 5.271556e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.559594e-08 0.000000e+00 3.54106e-06 0.000000e+00 9.775988e-08 5.297018e-07 5.244551e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.543719e-08 0.000000e+00 3.58321e-06 0.000000e+00 9.685555e-08 5.212361e-07 5.243078e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.528209e-08 0.000000e+00 3.6251e-06 0.000000e+00 9.599998e-08 5.106776e-07 5.261937e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.513169e-08 0.000000e+00 3.66673e-06 0.000000e+00 9.522452e-08 4.981649e-07 5.309171e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.498467e-08 0.000000e+00 3.7081e-06 0.000000e+00 9.447989e-08 4.834693e-07 5.399841e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.484131e-08 0.000000e+00 3.74922e-06 0.000000e+00 9.373951e-08 4.650713e-07 5.559061e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.470077e-08 0.000000e+00 3.79009e-06 0.000000e+00 9.302561e-08 4.428461e-07 5.819536e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.456339e-08 0.000000e+00 3.83071e-06 0.000000e+00 9.230840e-08 4.134616e-07 6.302120e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.442646e-08 0.000000e+00 3.87005e-06 0.000000e+00 8.938145e-08 3.709697e-07 7.065025e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.393026e-08 0.000000e+00 3.90524e-06 0.000000e+00 7.964536e-08 2.828025e-07 9.510157e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.239615e-08 0.000000e+00 3.93612e-06 0.000000e+00 7.408702e-08 3.766166e-07 6.964435e-07 0.000000e+00 0.000000e+00 0.000000e+00 1.131394e-08 0.000000e+00 -
rcf_sphere_laminar.zip
@sibo 这里面差个polyMesh，那个文件有点大。 -
观察输出的迭代信息，发现，U rhoU rhoE三个值始终残差为0，我以为是不需要设置求解的，尝试在fvsolution中注销掉了，发现计算运行时会报错，说这几个量没有定义。。。定义了好像又不求解。。这是怎么回事呢？
而且我rcf迭代中，final残差总是比final残差大。。几个量级。。
并发现，上一步的final并不是下一步的initial残差。这是怎么回事呀？
初始残差一般都是10的-7量级，怎么迭代后越来越大，但是下一步的初始残差还是e-7。。。 要被虐哭了，大佬帮帮我。deltaT = 8.38392e-08 Mean and max Courant Numbers = 0.010868 0.525071 Time = 4.93006e-07 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 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 = 6.98094e-07, Final residual = 3.53286e-05, No Iterations 1000 smoothSolver: Solving for Uy, Initial residual = 6.01407e-06, Final residual = 5.40888e-05, No Iterations 1000 smoothSolver: Solving for Uz, Initial residual = 2.91948e-06, Final residual = 2.84312e-05, No Iterations 1000 diagonal: Solving for rhoE, Initial residual = 0, Final residual = 0, No Iterations 0 smoothSolver: Solving for e, Initial residual = 7.3214e-08, Final residual = 0.000463259, No Iterations 1000 ExecutionTime = 48.36 s ClockTime = 54 s -
log.zip
上传一个log文件。。。 -
@RebelYoung
你这个log是rhoC的吧？你的case是inviscid还是viscous flow? rhoCentralFoam对待inviscid flow是用的explicit方法求解，所以假如你没有viscosity，用diagonal solver时，residual就是0. -
@RebelYoung
建议先查boundary conditions；还有mesh，你的checkMesh结果呢 -
以上基本描述的都是rhoCentralFoam问题，报错是Negative Initial Temperature，但是全场最小温度并没有负值。。
这个rcf_sphere_laminar是根据，$FOAM_TUTORIALS/compressible/rhoCentralFoam/obliqueShock改的。是层流计算，/0下设置了p，T，U三个量。
以下贴出rhoC 0下文件：
./0/pFoamFile { version 2.0; format ascii; class volScalarField; object p; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // dimensions [1 -1 -2 0 0 0 0]; internalField uniform 100000; boundaryField { ball { type zeroGradient; } inlet { type zeroGradient; } outlet { type fixedValue; value uniform 100000; } far { type zeroGradient; } }./0/T
FoamFile { version 2.0; format ascii; class volScalarField; object T; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // dimensions [0 0 0 1 0 0 0]; internalField uniform 270; boundaryField { ball { type zeroGradient; } inlet { type fixedValue; value uniform 270; } outlet { type zeroGradient; } far { type fixedValue; value uniform 270; } }./0/U
其中U从1到250，都算过。都出现能量方程发散或negative initial temperature问题。FoamFile { version 2.0; format ascii; class volVectorField; object U; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // dimensions [0 1 -1 0 0 0 0]; internalField uniform (1 0 0); boundaryField { ball { type noSlip; } inlet { type fixedValue; value uniform (1 0 0); } outlet { type zeroGradient; } far { type fixedValue; value uniform (1 0 0); } }checkMesh结果：
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // Create time Create polyMesh for time = 0 Time = 0 Mesh stats points: 28680 faces: 309924 internal faces: 293684 cells: 150902 faces per cell: 4 boundary patches: 4 point zones: 0 face zones: 0 cell zones: 0 Overall number of cells of each type: hexahedra: 0 prisms: 0 wedges: 0 pyramids: 0 tet wedges: 0 tetrahedra: 150902 polyhedra: 0 Checking topology... Boundary definition OK. Cell to face addressing OK. Point usage OK. Upper triangular ordering OK. Face vertices OK. Number of regions: 1 (OK). Checking patch topology for multiply connected surfaces... Patch Faces Points Surface topology ball 9780 4892 ok (closed singly connected) far 4404 2278 ok (non-closed singly connected) inlet 1028 553 ok (non-closed singly connected) outlet 1028 553 ok (non-closed singly connected) Checking geometry... Overall domain bounding box (-0.1 -0.1 -0.1) (0.1 0.1 0.1) Mesh has 3 geometric (non-empty/wedge) directions (1 1 1) Mesh has 3 solution (non-empty) directions (1 1 1) Boundary openness (1.54762e-16 -1.49987e-17 -1.09064e-16) OK. Max cell openness = 3.03063e-16 OK. Max aspect ratio = 5.29154 OK. Minimum face area = 3.38388e-08. Maximum face area = 0.000137468. Face area magnitudes OK. Min volume = 4.46514e-12. Max volume = 4.98913e-07. Total volume = 0.00799582. Cell volumes OK. Mesh non-orthogonality Max: 58.0988 average: 22.4508 Non-orthogonality check OK. Face pyramids OK. Max skewness = 0.67456 OK. Coupled point location match (average 0) OK. Mesh OK. End./constant/thermophysicalProperties: 此文件根据rhoS中计算翼型的文件修改，因为原算例是想控制mach数等原因，改的不符合物理性质，且mu=0。我将其改成了正常参数。
FoamFile { version 2.0; format ascii; class dictionary; location "constant"; object thermophysicalProperties; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // thermoType { type hePsiThermo; mixture pureMixture; transport const; thermo hConst; equationOfState perfectGas; specie specie; energy sensibleInternalEnergy; } mixture { // normalised gas specie { molWeight 28.9; } thermodynamics { Cp 1005; Hf 0; } transport { mu 1.8e-5; Pr 0.71; } }FoamFile { version 2.0; format ascii; class dictionary; location "constant"; object turbulenceProperties; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // simulationType laminar; -
最新看到的说法是，T估算值或者插值中出现了问题。比如方程解的是h，那么从h=cp(T)T中解出T的估算值，结果是负的。。
rhoC解的是e，那么e=CvT，cv基本不变，那应该是e出现负值导致T出现负值。。。
还是有这种类型的计算，只是我孤陋寡闻不知道。