Water jet interaction with supersonic air jet*

Spray formation following water jet injection into a supersonic air jet is investigated using various non-intrusive diagnostics. Spray characteristics are studied as a function of the jet injection location. High speed imaging is used to capture spray boundary while Phase Doppler Particle Anemometry (PDPA) is used to quantify drop size and velocity. The differences observed in the present setup from a traditional wall bounded jet-in-crossflow configuration are highlighted, including the lack of agreement with empirical relationships for spray penetration height. This is attempted to be overcome by developing new empirical relationships that take into account the diameters of the air and water jets using experimental data obtained for different sized water jets.