Study on the influence mechanism of geometric parameters of asymmetric fuel injectors on internal transient flow and cavitation characteristics

Abstract
In order to deeply analyze the influence of geometric parameters on the transient flow and cavitation characteristics inside asymmetric fuel injectors. Unlike previous steady-state analyses of symmetric nozzles, this research uniquely adopts a dynamic evolutionary perspective to capture the transient multiphase flow processes within a single injection event.. The evolution mechanism of pressure, velocity, gas phase volume fraction, and turbulence energy inside the nozzle under different geometric parameters was studied. The results show that increasing the nozzle diameter can increase the outlet flow velocity by 2.37% -3.27%, significantly enhance the cavitation effect, and reduce the average flow coefficient by about 9.3% -10%; Increasing the nozzle length will suppress the development of cavitation and reduce the outlet flow rate by 1.03% -1.69%; Increasing the inlet fillet radius can optimize the flow structure, increase the flow velocity by 1.68% -2.13%, increase the flow coefficient to 19.30%, and effectively suppress cavitation. The research results provide a theoretical basis for the performance of asymmetric fuel injectors.