Abstract
In this paper, a novel numerical model is established to conduct transient simulations of gas-liquid mass transfer in volume control tank (VCT). The surface divergence model was coupled with the CFD model to model the gas-liquid mass transfer near the interface. And the species transport model was used to model the homogeneous mass transfer inside the liquid. The simulated data is verified by experimental results. And the deviation between simulation results and experimental results is less than 6.67%. This model can accurately predict the gas-liquid mass transfer in VCT. Moreover, the flow field and concentration field in the VCT were analyzed. And the results show that there are three dominant mechanisms of gas-liquid mass transfer in VCT. The first mechanism is the entrainment of high-concentration fluids by surface jets at the gas-liquid interface. And the second is a double vortex structure above the jet inlet to pump the high-nitrogen-concentration fluid to a low-nitrogen-concentration area. The third is the mass exchange between the vortex at the end of the jet and the jet. Furthermore, the effects of thermal parameters (the temperature, operating pressure and inflow flow rate) on the VCT interface mass transfer process were also studied.
