Numerical investigation of velocity ratio effect in combined wall and offset jet flows

Abstract

In the present work, we propose to numerically study a combined turbulent wall and offset jet flow (this combination will be denoted WOJ). Several turbulence models were tested in this study: the standard k - ω, SST k - ω, standard k - e, RNG, and realizable k - e model. A parametric study was performed to determine the effect of offset ratio H and the velocity ratio r on the longitudinal and transverse positions of the merge point (MP), the combined point (CP), the upper vortex center (UVC) and the lower vortex center (LVC). Correlations that predict the position of these characteristic points of the WOJ flow as a function of H and r have been provided. Results show that any increase in the velocity ratio causes a displacement of the MP, CP, UVC and LVC further upstream along the longitudinal direction. Concerning the transverse positions, the increase of velocity ratio results in a deviation of the merge point (MP) and the lower vortex center (LVC) toward the strong jet (LWJ) whereas the transverse position of combined point (CP) and the upper vortex center (UVC) is almost independent of the velocity ratio.