Application of a two phase lattice Boltzmann model in simulation of free surface jet impingement heat transfer

In this paper a two-phase lattice Boltzmann model, capable of handling large density jumps, is used to study the free surface jet impingement cooling in the non-boiling regime. The multiple-relaxation-time (MRT) collision operator is employed to enhance the numerical stability of the model at high Reynolds numbers. The capability of the outlined two-phase LB scheme in accurate capturing of the interface shape is assessed through relevant test cases. These include the oscillating drop, Rayleigh-Taylor instability, and Kelvin-Helmholtz instability. In addition to demonstrate the validity of the model in simulation of heat transfer the predicted distribution of the Nu number on the impingement plate are compared with those of analytical results. The validated numerical solver then is employed to study a planar liquid jet emanating from a nozzle into a quiescent gas and impinging the opposite plate. The influence of the jet Re number and liquid-to-gas density ratio on the instantaneous flow field, interface shape, and heat transfer rate is also examined. This work reports for the first time the simulation of an impinging free surface liquid jet using a two phase lattice Boltzmann model.