怎样限制流场中最大速度
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各位前辈好！
我在compressibleInterFoam中引入了空化源项，现在调用自己写的非线性SGS模型计算的时候，流场初始速度10m/s，计算一段时间后，maxU会突然增大，导致流场发散掉，下面是速度暴增的过程
MULES: Solving for alpha.water Liquid phase volume fraction = 0.997517 Min(alpha.water) = 0.000412402 Max(alpha.water) = 1 Min(alpha.vapor) = -8.20677e-13 Max(alpha.vapor) = 0.999588 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 smoothSolver: Solving for T, Initial residual = 4.32259e-05, Final residual = 2.38488e-09, No Iterations 2 min(T) 290.144 GAMG: Solving for p_rgh, Initial residual = 4.54434e-06, Final residual = 7.05483e-10, No Iterations 3 max(U) 13.9186 min(p_rgh) 1843.8 GAMGPCG: Solving for p_rgh, Initial residual = 3.62757e-07, Final residual = 4.88638e-10, No Iterations 1 max(U) 13.9184 min(p_rgh) 1843.67 ExecutionTime = 275.32 s Integral of alpha.water = 0.00190802 [0 3 0 0 0 0 0] fieldAverage fieldAverage1 output: Calculating averages Courant Number mean: 0.00487524 max: 0.135574 Time = 0.011952 MULES: Solving for alpha.water Liquid phase volume fraction = 0.997517 Min(alpha.water) = 0.000413145 Max(alpha.water) = 1 Min(alpha.vapor) = -4.79172e-13 Max(alpha.vapor) = 0.999587 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 smoothSolver: Solving for T, Initial residual = 4.324e-05, Final residual = 2.42709e-09, No Iterations 2 min(T) 290.146 GAMG: Solving for p_rgh, Initial residual = 5.42286e-06, Final residual = 7.32723e-10, No Iterations 3 max(U) 26.57 min(p_rgh) 1813.11 GAMGPCG: Solving for p_rgh, Initial residual = 3.66982e-07, Final residual = 5.21535e-10, No Iterations 1 max(U) 25.4251 min(p_rgh) 1817.97 ExecutionTime = 275.6 s fieldAverage fieldAverage1 output: Calculating averages Courant Number mean: 0.00487537 max: 0.135663 Time = 0.011953 MULES: Solving for alpha.water Liquid phase volume fraction = 0.997517 Min(alpha.water) = 0.000412369 Max(alpha.water) = 1 Min(alpha.vapor) = -8.14016e-13 Max(alpha.vapor) = 0.999588 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 smoothSolver: Solving for T, Initial residual = 4.32537e-05, Final residual = 2.41625e-09, No Iterations 2 min(T) 290.148 GAMG: Solving for p_rgh, Initial residual = 5.31025e-06, Final residual = 6.64697e-10, No Iterations 3 max(U) 20.2828 min(p_rgh) 1797.39 GAMGPCG: Solving for p_rgh, Initial residual = 3.95326e-07, Final residual = 5.53382e-10, No Iterations 1 max(U) 20.6401 min(p_rgh) 1803.66 ExecutionTime = 275.88 s fieldAverage fieldAverage1 output: Calculating averages Courant Number mean: 0.00487547 max: 0.135752 Time = 0.011954 MULES: Solving for alpha.water Liquid phase volume fraction = 0.997516 Min(alpha.water) = 0.000412357 Max(alpha.water) = 1 Min(alpha.vapor) = -2.22555e-12 Max(alpha.vapor) = 0.999588 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 smoothSolver: Solving for T, Initial residual = 4.32478e-05, Final residual = 2.41079e-09, No Iterations 2 min(T) 290.15 GAMG: Solving for p_rgh, Initial residual = 4.91279e-06, Final residual = 6.3296e-10, No Iterations 3 max(U) 30.2344 min(p_rgh) 1778.9 GAMGPCG: Solving for p_rgh, Initial residual = 4.09173e-07, Final residual = 3.01626e-10, No Iterations 1 max(U) 29.9168 min(p_rgh) 1779.32 ExecutionTime = 276.17 s fieldAverage fieldAverage1 output: Calculating averages Courant Number mean: 0.00487556 max: 0.135842 Time = 0.011955 MULES: Solving for alpha.water Liquid phase volume fraction = 0.997516 Min(alpha.water) = 0.000412479 Max(alpha.water) = 1 Min(alpha.vapor) = -4.44089e-16 Max(alpha.vapor) = 0.999588 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 smoothSolver: Solving for T, Initial residual = 4.32198e-05, Final residual = 2.70013e-09, No Iterations 2 min(T) 290.153 GAMG: Solving for p_rgh, Initial residual = 1.71158e-05, Final residual = 7.83321e-10, No Iterations 4 max(U) 140.097 min(p_rgh) 1138.55 GAMGPCG: Solving for p_rgh, Initial residual = 1.088e-06, Final residual = 4.13587e-10, No Iterations 2 max(U) 147.712 min(p_rgh) 1226.71 ExecutionTime = 276.46 s我仔细检查发现很可能是由于求解U方程时，某个网格上面速度突然变得很大，最终导致流场发散，目前想在U方程中 或者 P方程中限制最大速度不超过某一个值，由于U是矢量，我现在不太清楚怎么限制流场中的U不超过某一个值呢？是分别限制U某一方向的速度 还是 直接限制max(mag(U).value)呢？
麻烦哪位前辈能够指点一下呢？谢谢
