Numerical Investigation of a Liquid-Gas Ejector in Marine Ships

摘要

The purpose of the current study is performance evaluation of a gas-liquid jet ejector under various conditions numerically. A commercial code ANSYS-CFX has been adopted to solve the computational model. To solve velocity fields of air and water separately mixture model was implemented for the current study. For accurate turbulent boundary layer prediction in the nozzle and mixing flow in the mixing chamber, SST turbulence model was opted. Motive air pressure, suction side pressure and S/D_(th) were varied to see their effect on the secondary fluid flow rate and ratio of secondary to primary flow rate. Mover over flow behavior of primary and secondary fluid in the nozzle wake and mixing chamber has been discussed with various applied conditions. It was evaluated that ratio of secondary to primary fluid flow rate increasing with the increase of motive air pressure initially and then becomes constant at some value of motive air pressure. Moreover maximum flow rate of the secondary fluid was achieved at S/D_(th) = 1.