缩尺模型发散



  • 遇到一个奇怪的事情,在做模拟的时候,用足尺模型计算可以正常算,做缩尺模型的时候就会发散
    我做的二维模拟,厚度方向只有一层网格,边界条件按论文设置的,论文用fluent算的缩尺模型,我放大到足尺模型算没有问题,但是按论文的尺寸算,第一步Uz就是solution singularity,算着算着epsilon就发散了,很奇怪。我用的simpleFoam,大家有啥建议吗,按理说应该能算啊。。。

    RAS
    {
        RASModel        realizableKE;
        turbulence      on;
        printCoeffs     on;
        A0              4;
        C2              1.9;
        sigmak          1;
        sigmaEps        1.2;
    }
    
    No MRF models present
    
    No finite volume options present
    
    Starting time loop
    
    wallShearStress wallShearStress:
        processing all wall patches
    
    Time = 0.01
    
    DILUPBiCGStab:  Solving for Ux, Initial residual = 1, Final residual = 9.02931e-11, No Iterations 5
    DILUPBiCGStab:  Solving for Uz:  solution singularity
    GAMG:  Solving for p, Initial residual = 1, Final residual = 0.0511143, No Iterations 14
    GAMG:  Solving for p, Initial residual = 9.35553e-05, Final residual = 7.3953e-06, No Iterations 2
    time step continuity errors : sum local = 5.93648e-05, global = -2.24242e-05, cumulative = -2.24242e-05
    DILUPBiCGStab:  Solving for epsilon, Initial residual = 0.141893, Final residual = 1.91784e-12, No Iterations 5
    DILUPBiCGStab:  Solving for k, Initial residual = 1, Final residual = 2.77584e-10, No Iterations 5
    ExecutionTime = 1.25 s  ClockTime = 2 s
    
    Time = 0.02
    
    DILUPBiCGStab:  Solving for Ux, Initial residual = 0.527912, Final residual = 5.42646e-12, No Iterations 5
    DILUPBiCGStab:  Solving for Uz, Initial residual = 0.587444, Final residual = 1.93572e-11, No Iterations 5
    GAMG:  Solving for p, Initial residual = 0.0040408, Final residual = 0.000253175, No Iterations 4
    GAMG:  Solving for p, Initial residual = 0.00119141, Final residual = 0.000118566, No Iterations 6
    time step continuity errors : sum local = 0.000903519, global = 0.000115926, cumulative = 9.35023e-05
    DILUPBiCGStab:  Solving for epsilon, Initial residual = 0.00632051, Final residual = 4.41338e-13, No Iterations 5
    DILUPBiCGStab:  Solving for k, Initial residual = 0.93484, Final residual = 9.44193e-11, No Iterations 5
    ExecutionTime = 1.75 s  ClockTime = 2 s
    
    Time = 0.03
    
    DILUPBiCGStab:  Solving for Ux, Initial residual = 0.296853, Final residual = 3.58872e-10, No Iterations 5
    DILUPBiCGStab:  Solving for Uz, Initial residual = 0.358972, Final residual = 3.93449e-10, No Iterations 5
    GAMG:  Solving for p, Initial residual = 0.0399261, Final residual = 0.00208552, No Iterations 1
    GAMG:  Solving for p, Initial residual = 0.00341154, Final residual = 0.000273619, No Iterations 7
    time step continuity errors : sum local = 0.00196847, global = 0.0002969, cumulative = 0.000390402
    DILUPBiCGStab:  Solving for epsilon, Initial residual = 0.0295801, Final residual = 9.2042e-13, No Iterations 5
    DILUPBiCGStab:  Solving for k, Initial residual = 0.171095, Final residual = 5.49745e-10, No Iterations 5
    ExecutionTime = 2.22 s  ClockTime = 3 s
    
    Time = 0.04
    
    DILUPBiCGStab:  Solving for Ux, Initial residual = 0.136215, Final residual = 5.49597e-11, No Iterations 5
    DILUPBiCGStab:  Solving for Uz, Initial residual = 0.31202, Final residual = 1.31588e-10, No Iterations 5
    GAMG:  Solving for p, Initial residual = 0.130254, Final residual = 0.00470188, No Iterations 1
    GAMG:  Solving for p, Initial residual = 0.00639474, Final residual = 0.000576745, No Iterations 8
    time step continuity errors : sum local = 0.00159515, global = 0.000184109, cumulative = 0.000574511
    DILUPBiCGStab:  Solving for epsilon, Initial residual = 0.0325781, Final residual = 7.34046e-12, No Iterations 5
    DILUPBiCGStab:  Solving for k, Initial residual = 0.150909, Final residual = 1.5092e-10, No Iterations 5
    ExecutionTime = 2.72 s  ClockTime = 3 s
    
    Time = 0.05
    
    DILUPBiCGStab:  Solving for Ux, Initial residual = 0.309871, Final residual = 7.73697e-11, No Iterations 5
    DILUPBiCGStab:  Solving for Uz, Initial residual = 0.461963, Final residual = 1.28081e-10, No Iterations 5
    GAMG:  Solving for p, Initial residual = 0.167412, Final residual = 0.00510895, No Iterations 1
    GAMG:  Solving for p, Initial residual = 0.00610619, Final residual = 0.000483956, No Iterations 7
    time step continuity errors : sum local = 0.00101936, global = 5.21071e-05, cumulative = 0.000626618
    DILUPBiCGStab:  Solving for epsilon, Initial residual = 0.00882784, Final residual = 7.51562e-13, No Iterations 5
    DILUPBiCGStab:  Solving for k, Initial residual = 0.236641, Final residual = 6.08151e-11, No Iterations 5
    ExecutionTime = 3.2 s  ClockTime = 3 s
    
    Time = 0.06
    
    DILUPBiCGStab:  Solving for Ux, Initial residual = 0.341882, Final residual = 1.0659e-10, No Iterations 5
    DILUPBiCGStab:  Solving for Uz, Initial residual = 0.454444, Final residual = 1.41636e-10, No Iterations 5
    GAMG:  Solving for p, Initial residual = 0.132903, Final residual = 0.00323376, No Iterations 1
    GAMG:  Solving for p, Initial residual = 0.00381782, Final residual = 0.000236562, No Iterations 6
    time step continuity errors : sum local = 0.000731669, global = -0.000105249, cumulative = 0.000521369
    DILUPBiCGStab:  Solving for epsilon, Initial residual = 0.0075595, Final residual = 4.3385e-12, No Iterations 5
    DILUPBiCGStab:  Solving for k, Initial residual = 0.192427, Final residual = 3.91865e-10, No Iterations 5
    ExecutionTime = 3.68 s  ClockTime = 4 s
    
    Time = 0.07
    
    DILUPBiCGStab:  Solving for Ux, Initial residual = 0.282586, Final residual = 2.67545e-10, No Iterations 5
    DILUPBiCGStab:  Solving for Uz, Initial residual = 0.35265, Final residual = 2.45834e-10, No Iterations 5
    GAMG:  Solving for p, Initial residual = 0.151323, Final residual = 0.00331011, No Iterations 1
    GAMG:  Solving for p, Initial residual = 0.00398265, Final residual = 0.000390266, No Iterations 5
    time step continuity errors : sum local = 0.00105724, global = -8.7694e-05, cumulative = 0.000433675
    DILUPBiCGStab:  Solving for epsilon, Initial residual = 0.00759443, Final residual = 1.21657e-12, No Iterations 5
    DILUPBiCGStab:  Solving for k, Initial residual = 0.18612, Final residual = 3.54752e-11, No Iterations 5
    ExecutionTime = 4.13 s  ClockTime = 4 s
    
    Time = 0.08
    
    DILUPBiCGStab:  Solving for Ux, Initial residual = 0.213044, Final residual = 6.05622e-11, No Iterations 5
    DILUPBiCGStab:  Solving for Uz, Initial residual = 0.28304, Final residual = 9.67631e-11, No Iterations 5
    GAMG:  Solving for p, Initial residual = 0.189574, Final residual = 0.00373539, No Iterations 1
    GAMG:  Solving for p, Initial residual = 0.00463947, Final residual = 0.000336507, No Iterations 7
    time step continuity errors : sum local = 0.000557299, global = -5.79127e-05, cumulative = 0.000375763
    DILUPBiCGStab:  Solving for epsilon, Initial residual = 0.00781571, Final residual = 1.93204e-12, No Iterations 5
    DILUPBiCGStab:  Solving for k, Initial residual = 0.138057, Final residual = 3.95958e-11, No Iterations 5
    ExecutionTime = 4.62 s  ClockTime = 5 s
    
    Time = 0.09
    
    DILUPBiCGStab:  Solving for Ux, Initial residual = 0.237589, Final residual = 2.96319e-11, No Iterations 5
    DILUPBiCGStab:  Solving for Uz, Initial residual = 0.243097, Final residual = 1.46831e-10, No Iterations 5
    GAMG:  Solving for p, Initial residual = 0.180488, Final residual = 0.00312019, No Iterations 1
    GAMG:  Solving for p, Initial residual = 0.00383925, Final residual = 0.00026896, No Iterations 7
    time step continuity errors : sum local = 0.00035406, global = -2.62236e-05, cumulative = 0.000349539
    DILUPBiCGStab:  Solving for epsilon, Initial residual = 0.006831, Final residual = 3.72725e-13, No Iterations 5
    DILUPBiCGStab:  Solving for k, Initial residual = 0.126435, Final residual = 2.17405e-11, No Iterations 5
    ExecutionTime = 5.09 s  ClockTime = 5 s
    
    Time = 0.1
    
    DILUPBiCGStab:  Solving for Ux, Initial residual = 0.35012, Final residual = 3.04751e-11, No Iterations 5
    DILUPBiCGStab:  Solving for Uz, Initial residual = 0.30704, Final residual = 8.67602e-11, No Iterations 5
    GAMG:  Solving for p, Initial residual = 0.149198, Final residual = 0.00253316, No Iterations 1
    GAMG:  Solving for p, Initial residual = 0.00305357, Final residual = 0.000284755, No Iterations 5
    time step continuity errors : sum local = 0.000375062, global = 2.83423e-05, cumulative = 0.000377881
    DILUPBiCGStab:  Solving for epsilon, Initial residual = 0.00611188, Final residual = 1.87536e-13, No Iterations 5
    DILUPBiCGStab:  Solving for k, Initial residual = 0.289974, Final residual = 2.50168e-11, No Iterations 5
    ExecutionTime = 5.88 s  ClockTime = 6 s
    
    wallShearStress wallShearStress write:
        writing field wallShearStress
        min/max(down) = (-2.87883 -3.63059e-22 -0.0927051), (0.461882 3.65848e-22 0.0998493)
        min/max(roof) = (-17.9474 -1.26777e-18 -3.09904), (-0.42612 1.16826e-18 6.57279)
        min/max(buildingWall) = (-6.27984 -1.34705e-19 -2.37151), (0.222287 1.01572e-19 6.15707)
    Time = 0.11
    
    DILUPBiCGStab:  Solving for Ux, Initial residual = 0.531763, Final residual = 2.03224e-12, No Iterations 5
    DILUPBiCGStab:  Solving for Uz, Initial residual = 0.56992, Final residual = 2.11653e-12, No Iterations 5
    GAMG:  Solving for p, Initial residual = 0.153026, Final residual = 0.00256444, No Iterations 1
    GAMG:  Solving for p, Initial residual = 0.00310925, Final residual = 0.000212052, No Iterations 7
    time step continuity errors : sum local = 0.00026462, global = 1.89049e-05, cumulative = 0.000396786
    DILUPBiCGStab:  Solving for epsilon, Initial residual = 0.0049126, Final residual = 9.09796e-14, No Iterations 5
    DILUPBiCGStab:  Solving for k, Initial residual = 0.282556, Final residual = 9.72273e-13, No Iterations 5
    ExecutionTime = 6.4 s  ClockTime = 7 s
    
    Time = 0.12
    
    DILUPBiCGStab:  Solving for Ux, Initial residual = 0.23185, Final residual = 1.68742e-11, No Iterations 5
    DILUPBiCGStab:  Solving for Uz, Initial residual = 0.377097, Final residual = 1.61394e-11, No Iterations 5
    GAMG:  Solving for p, Initial residual = 0.175782, Final residual = 0.0040422, No Iterations 1
    GAMG:  Solving for p, Initial residual = 0.00486161, Final residual = 0.000340632, No Iterations 5
    time step continuity errors : sum local = 0.000478204, global = 5.30041e-05, cumulative = 0.00044979
    DILUPBiCGStab:  Solving for epsilon, Initial residual = 0.00552237, Final residual = 1.23137e-13, No Iterations 5
    DILUPBiCGStab:  Solving for k, Initial residual = 0.394754, Final residual = 2.5363e-11, No Iterations 5
    ExecutionTime = 6.84 s  ClockTime = 7 s
    
    Time = 0.13
    
    DILUPBiCGStab:  Solving for Ux, Initial residual = 0.379743, Final residual = 1.63324e-11, No Iterations 5
    DILUPBiCGStab:  Solving for Uz, Initial residual = 0.230827, Final residual = 4.62169e-12, No Iterations 5
    GAMG:  Solving for p, Initial residual = 0.207157, Final residual = 0.00627811, No Iterations 1
    GAMG:  Solving for p, Initial residual = 0.00764946, Final residual = 0.000568072, No Iterations 7
    time step continuity errors : sum local = 0.000345064, global = 3.01655e-05, cumulative = 0.000479956
    DILUPBiCGStab:  Solving for epsilon, Initial residual = 0.00351726, Final residual = 8.00546e-14, No Iterations 5
    DILUPBiCGStab:  Solving for k, Initial residual = 0.386289, Final residual = 1.57371e-13, No Iterations 5
    ExecutionTime = 7.33 s  ClockTime = 8 s
    
    Time = 0.14
    
    DILUPBiCGStab:  Solving for Ux, Initial residual = 0.649438, Final residual = 4.46392e-16, No Iterations 5
    DILUPBiCGStab:  Solving for Uz, Initial residual = 0.506957, Final residual = 1.07223e-16, No Iterations 5
    GAMG:  Solving for p, Initial residual = 0.156169, Final residual = 0.00375195, No Iterations 1
    GAMG:  Solving for p, Initial residual = 0.00165985, Final residual = 0.000160854, No Iterations 3
    time step continuity errors : sum local = 0.00058144, global = 7.92418e-06, cumulative = 0.00048788
    DILUPBiCGStab:  Solving for epsilon, Initial residual = 0.00170993, Final residual = 2.94273e-17, No Iterations 5
    DILUPBiCGStab:  Solving for k, Initial residual = 0.329833, Final residual = 1.51244e-18, No Iterations 5
    ExecutionTime = 7.77 s  ClockTime = 8 s
    
    Time = 0.15
    
    DILUPBiCGStab:  Solving for Ux, Initial residual = 0.571959, Final residual = 3.32197e-16, No Iterations 5
    DILUPBiCGStab:  Solving for Uz, Initial residual = 0.458761, Final residual = 1.52795e-17, No Iterations 5
    GAMG:  Solving for p, Initial residual = 0.0452743, Final residual = 0.00151925, No Iterations 1
    GAMG:  Solving for p, Initial residual = 0.00267839, Final residual = 0.000230421, No Iterations 1
    time step continuity errors : sum local = 0.00342145, global = -1.32423e-05, cumulative = 0.000474638
    DILUPBiCGStab:  Solving for epsilon, Initial residual = 0.000546564, Final residual = 2.02553e-17, No Iterations 5
    DILUPBiCGStab:  Solving for k, Initial residual = 0.130893, Final residual = 2.82138e-19, No Iterations 5
    ExecutionTime = 8.17 s  ClockTime = 8 s
    
    Time = 0.16
    
    DILUPBiCGStab:  Solving for Ux, Initial residual = 0.463509, Final residual = 1.57563e-17, No Iterations 5
    DILUPBiCGStab:  Solving for Uz, Initial residual = 0.509736, Final residual = 4.59172e-18, No Iterations 5
    GAMG:  Solving for p, Initial residual = 0.134174, Final residual = 0.00768087, No Iterations 2
    GAMG:  Solving for p, Initial residual = 0.00363852, Final residual = 0.000201176, No Iterations 4
    time step continuity errors : sum local = 0.0210048, global = -0.000201257, cumulative = 0.000273381
    DILUPBiCGStab:  Solving for epsilon, Initial residual = 0.00400355, Final residual = 8.29593e-18, No Iterations 5
    DILUPBiCGStab:  Solving for k, Initial residual = 0.366453, Final residual = 1.20683e-18, No Iterations 5
    ExecutionTime = 8.63 s  ClockTime = 9 s
    
    Time = 0.17
    
    DILUPBiCGStab:  Solving for Ux, Initial residual = 0.267952, Final residual = 4.29013e-23, No Iterations 5
    DILUPBiCGStab:  Solving for Uz, Initial residual = 0.540221, Final residual = 5.71911e-22, No Iterations 5
    GAMG:  Solving for p, Initial residual = 0.123787, Final residual = 0.00286107, No Iterations 1
    GAMG:  Solving for p, Initial residual = 6.716e-05, Final residual = 3.30864e-06, No Iterations 6
    time step continuity errors : sum local = 1172.79, global = -133.626, cumulative = -133.626
    DILUPBiCGStab:  Solving for epsilon, Initial residual = 0.00118844, Final residual = 9.31074e-18, No Iterations 5
    DILUPBiCGStab:  Solving for k, Initial residual = 0.43358, Final residual = 1.23182e-16, No Iterations 5
    ExecutionTime = 9.1 s  ClockTime = 9 s
    
    Time = 0.18
    
    DILUPBiCGStab:  Solving for Ux, Initial residual = 0.699964, Final residual = 2.85242e-22, No Iterations 5
    DILUPBiCGStab:  Solving for Uz, Initial residual = 0.654102, Final residual = 3.34865e-22, No Iterations 5
    GAMG:  Solving for p, Initial residual = 0.1765, Final residual = 8.0125e-05, No Iterations 1
    GAMG:  Solving for p, Initial residual = 0.332435, Final residual = 0.0152816, No Iterations 1
    time step continuity errors : sum local = 7.41639e+18, global = 2.63517e+13, cumulative = 2.63517e+13
    DILUPBiCGStab:  Solving for epsilon, Initial residual = 2.32053e-07, Final residual = 1.76158e-19, No Iterations 5
    bounding epsilon, min: -70.8119 max: 8.51758e+10 average: 6.33029e+06
    DILUPBiCGStab:  Solving for k, Initial residual = 1, Final residual = 4.21351e-16, No Iterations 5
    ExecutionTime = 9.51 s  ClockTime = 10 s
    
    


  • 似乎是网格尺寸的原因,我把速度缩小10倍,能算了,说明以前的Y+可能有问题



  • 感觉是不是fluent有什么黑科技,在fluent里能算,在of里发散了。。


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