High-pressure liquid fuel injection: Evaluation of a novel three-component cavitation model for enhanced energy performance

Cavitation inside microscale injector nozzles is a multiscale phenomenon governed by the coupled effects of vortex evolution, pressure fluctuations, phase transition, and multicomponent transport. With the increasing application of carbon-neutral fuels such as methanol and liquid ammonia, their relatively high saturated vapor pressure and dissolved-gas content further complicate cavitation behavior and make it more sensitive to local flow conditions. Among the unresolved physical issues of vortex cavitation, the role of non-condensable gases in swirl flow remains poorly understood, although these gases may play an important role in cavitation development by modifying the local pressure field and interphase mass transfer process. This study uses high-fidelity numerical simulations to build and evaluate a three-component cavitation model that accounts for the dynamics of non-condensable gases. Results show that the concentration of non-condensable gases within the vortex flow field is closely related to the vortex pressure. In the three-component cavitation model, non-condensable gases have a dual regulatory influence on the fuel liquid-vapor phase transition process by simultaneously modulating the critical pressure for phase transition and the mass transfer rate. This mechanism delays bubble collapse and promotes the sustained development of vapor structures, resulting in improved agreement with the experimentally observed vortex-cavitation characteristics under the investigated operating condition compared with the conventional finite-rate mass transfer models. This study clarifies the regulatory pathways of non-condensable gases during cavitation inception and development, providing numerical support for spray control in carbon-neutral high-pressure fuel injection systems.