IMPINGEMENT OF SINGLE AND TWIN TURBULENT JETS THROUGH A CROSS-FLOW

Laser-Doppler measurements of velocity characteristics of the flowfield resulting from the impingement of single and twin jets against a wall through a low-velocity crossflow are presented and discussed together with visualization of the flow. The experiments have been carried out for a velocity ratio between the jets and the crossflow of 30, for a Reynolds number based on the jet exit Re(j) between 60,000 and 105,000, and for the jet exit 5 jet diameters above the ground plate. In addition, calculations based on a two-equation turbulence model are presented for the three-dimensional flow characterized by the measurements, and comparison between experimental and numerical results show that the mean flowfield is well predicted. The calculation of the turbulent field requires, however, consideration of the individual stresses.