小
大家好！
最近再尝试用LES模拟水翼空化流动，用了400W的网格和interPhaseChangeFoam求解器，前期计算发现比较稳定，到0.3s之后就突然不正常了，有没有人用比较密的网格计算过水翼空化？
我原始设置的是固定时间步2.5*e-06,我感觉可能是时间步有点大了，但更改之后效果也不是很明显
ps:我之前用200w网格计算，效果很好，并没有出现类似的问题
下图是监控的 云空化空穴体积随时间变化图，前面好好地，后面就有问题了。。。
controlDict文件代码
// Foam Application Class
application interPhaseChangeFoam;
// Start point of run
//startFrom latestTime;
startFrom latestTime;
// Calculation start time
startTime 0;//0.399;//0;
// End point of run
stopAt endTime;
// Calculation end time
endTime 0.5;//0.9;//5.0e-2;
// Calculation time step
deltaT 2.5e-06;//2.0e-5;//
// Type of write output control
writeControl adjustableRunTime;
// Interval with which the results are output
writeInterval 1.0e-3;
// Limits number of time directories before overwriting
cycleWrite 0;
// Write Format
writeFormat ascii;
// Significant figures of written ASCII data
writePrecision 6;
// Write Compression
writeCompression uncompressed;
// Time directories name format
timeFormat general;
// Decimal precision of time directory names
timePrecision 6;
// Can parameters be modified during run time?
runTimeModifiable yes;
// Automatic adjustment of time step?
adjustTimeStep off;
// maxCo
maxAlphaCo 0.99; // 0.2; Victor Changes to remain with courant number < 1
// maxDeltaT
maxDeltaT 1e-2; // 1; Control the changes of delta calculation for a courant number < 1
fvSchemes文件
ddtSchemes
{
default Euler;
}
gradSchemes
{
default Gauss linear;
}
divSchemes
{
default none;
div(phi,alpha) Gauss upwind;
div(phirb,alpha) Gauss linear;
div(phi,rho) Gauss limitedLinear 1;
div(rhoPhi,U) Gauss upwind;
div(phi,thermo:rho.water) Gauss upwind;
div(phi,thermo:rho.air) Gauss upwind;
div(rhoPhi,T) Gauss upwind;
div(rhoPhi,K) Gauss upwind;
div(phi,p) Gauss upwind;
div(phi,k) Gauss upwind;
div(rhoPhi,omega) Gauss limitedLinear 1;
div(phi,omega) Gauss upwind;
div(rhoPhi,k) Gauss upwind;
div(((rho*nuEff)*dev2(T(grad(U))))) Gauss linear;
}
laplacianSchemes
{
default Gauss linear uncorrected;
}
interpolationSchemes
{
default linear;
}
snGradSchemes
{
default uncorrected;
}
wallDist
{
method meshWave;
}
一般这样 网格量很大的情况，用LES计算非定常问题，需要注意什么呢？
求各位指点！
