Mixing of jet in crossflow: Effects of jet geometry

Present work studied the effects of jet geometry on mixing of jet in crossflow. In this study the crossflow was a confined crossflow flowing through vertical duct with square cross-section. Duct geometry was kept constant throughout the study. Three jet geometry, Single jet, three jets in cross-stream direction and slot in cross-stream directions were studied. Temperature was used as an indicator for deciding the degree of mixing. Velocity ratio, defined as ratio of jet velocity to the crossflow velocity, was varied during the analysis. Four different values of velocity ratio were considered during the study. Effect of variation of crossflow Reynolds number as well as turbulence model on mixing was studied. Results were extracted for three jet geometry with different spacing and different number of jets. Slot jet geometry was tested for different aspect ratios. Computational fluid dynamics analysis was performed using commercial CFD software CFX 5.5. Results were extracted in the form of temperature field, temperature profiles and velocity vector plots. Analysis was validated by solving the similar problem in CFX 5.5 and comparing the results with the experimental results.; From the results obtained it can be concluded that, velocity ratio is the important controlling parameter in mixing of jet in crossflow. Slot geometry with small aspect ratio gives better mixing for the given conditions. Counter rotating vortex pair (CVP) is a mixing mechanism in the single round jet geometry.