cav_difu_orders

Summary: Stabilize cavitation simulations

Flag

cav_difu_orders A

A = number of orders of magnitude difference between the cavitation equation (liquid volume fraction) diffusion coefficient and the momentum equations

Description

A < 0

The liquid fraction equation diffusion coefficient is A orders of magnitude less than the viscosity. (For example, if A = -3, the diffusion coefficient = 0.001 * viscosity).

A > 0

The diffusion coefficient is A times larger than the viscosity. (For example, if A = 4, the diffusion coefficient = 10000 * viscosity.)

Diffusion plays numerically stabilizes the cavitation solution. The default value is -6, so by default, the diffusion is 0.000001 * viscosity.

If the solution experiences convergence difficulties, increase the value. A value of -3 increases the diffusion coefficient to 0.001 * viscosity. This often provides greater stabilization.

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