A numerical study on cryogenic sprays under different break-up regimes

CFD simulation of cryogenic sprays represents a challenging task that requires an accurate modeling of the specific thermodynamic-induced primary break-up and evaporation rate. This work presents a computational approach based on the Eulerian–Lagrangian framework to simulate cryogenic flashing sprays. Dedicated models are included to account for flash boiling in atomization, nozzle flow and phase change processes, removing the need to tune conventional break-up models to describe the spray evolution when flash boiling atomizing takes place. The proposed methodology is validated using experimental measurements of local spray properties (velocity, droplet diameter and temperature). The proposed model accurately captures the characteristics of the different breakup regimes (mechanical, transient and fully flashing break-up) reproducing experimental data both in terms of spray morphology and the thermophysical evolution of the vapor and liquid phases.