Numerical simulation of liquid film converge characteristics of bipropellant pressure swirl injector

To study the convergence characteristics of the liquid film of a bipropellant pressure-swirl injector, numerical investigation of bipropellant pressure swirl injector was conducted based on the volume of fluid (VOF) coupled Level Set methods under different thruster chamber pressures and pressure drops. The atomization characteristics of the injector were analyzed, and the law of mutual influence between the inner and outer nozzle liquid films was revealed. The results showed that when the pressure drop of outer nozzle was greater than 1.6 MPa, the convergence phenomenon occurred, and the inner and outer spray films were gradually overlapped and converged with each other in the process. After convergence, the downstream speed of the injector outlet relatively decreased. The increase of the thrust chamber pressure led to the shortening of the convergence time, while the influence of the pressure drop on the convergence time was relatively small. With the increase of the pressure drop, the convergence time decreased at first and then increased. © 2024 Beijing University of Aeronautics and Astronautics (BUAA). All rights reserved.