Pressure evolution lattice-Boltzmann-equation method for two-phase flow with phase change.
A lattice-Boltzmann-equation method for nonideal gases augmented by the pressure evolution equation is proposed to simulate isothermal two-phase fluid flow with phase change. The pressure evolution equation is derived by taking time derivative of the equation of state for nonideal gases. Unlike previous methods that use the equation of state to update pressure, the pressure field is evolved using the pressure evolution equation. The new approach has two advantages. First, it can avoid spurious pressure fluctuations at phase interfaces that develop owing to the pressure update by the equation of state, thus improving numerical stability of the method. Second, it permits compressibility of the fluid at phase interfaces when phase change occurs due to pressurization and depressurization. The proposed method is applied to simulate an isothermal phase change process. The numerical result is in excellent agreement with the analytical solution.
Lee
Taehun
T
Department of Mechanical and Industrial Engineering, IIHR-Hydroscience & Engineering, The University of Iowa, Iowa City, IA 52242, USA.
Lin
Ching-Long
CL