Gross-entrainment behavior of turbulent jets injected obliquely into a uniform crossflow

Turbulent jets injected at various inclinations into a uniform crossflow ha ve been studied using Mie-scattering dow visualization and image-processing techniques. Injection angles ranging from -45 to 45 deg from the normal di rection to the crossflow have been studied for the square root of momentum ratio ranging from 5 to 20, Instantaneous and ensemble-averaged images were obtained for each jet configuration, and their centerline trajectories wer e determined. A skewed coordinate system that accommodates changes in injec tion angle of the jets was used with a power-law equation to collapse the t rajectories to a single profile. Combining this correlation of the jet cent erline with the conservation equations of mass and momentum, an algebraic e xpression was derived to estimate the mass entrained by deflected jets. A j et with negative injection angles entrains the crossflow fluid more efficie ntly, leading to more rapid and compact mixing.