[Tingyun YIN]

Could anyone who successfully simulate the phase change with interPhaseChangeFoam share the experience?

OF 7.0, default interPhaseChangeFoam, 2D hydrofoil, LES;

Inlet velocity, outlet static pressure;

10 pimples, 5 pressure correction loops, 3 non-ortho corrections;

CFL is less than 0.25;

with / without relaxation factor, pressure field 0.3 while others 0.7;

However, the monitor maximum pressure has strong spikes and oscillations, not to mention of lift or drag, shown in fig. Another fig only shows the the initial residual which looks like getting convergence cause we all know the final residual will arrive the targets (1E-8).

Any comments of these spikes?

1.png

2.png

[Tingyun YIN]

All right, these oscillations and spikes might caused by the high order numerical schemes.

More aggressive limiters were used in the fvSchemes. Moreover, PIMPLE loops were increased up to 30.

fig shows a little improvement of the stabilization of max pressure monitored throughout the whole domain. These spikes seem to be unavoidable in the phase change field with high density ratio, especially for cloud cavitation.

Regarding the stable sheet cavity, the numerical solution of Default interPhaseChangeFoam works fine as expected.

boundary conditions? numerical schemes? Rhie-Chow interplation? limitations of density ratio as 1000? empirical coefficients of phase change model? To stabilize the pressure field, any comments of Default interPhaseChangeFoam are welcome.

Or the convergence of Default interPhaseChangeFoam is decided by 01. the residual and 02. periodical behaviors of volume integral alpha.vapour, without care of domainminandmax variables?