An experimental study on the droplets dynamics of flashing spray with R134a

Flashing spray is a common phenomenon which finds many applications in the industry, such as flash-spray internal combustion engine, distillation of salt water by flashing evaporation, cryogen spray cooling in dermatology. In order to improve the understanding of atomization mechanism, this paper presents an experimental investigation to the droplets dynamics in the R134a flashing spray including the variations of droplets diameter and velocities. The droplets diameter, droplets axial velocity and radial velocity at different locations are simultaneously measured by the PDPA system. The PDPA measurements data find that both the non-dimensional velocities show self-similar profile. Two empirical equations have been proposed to describe the non-dimensional velocities.