Predictions of a film coolant jet in crossflow with different turbulence models

This study investigates the performance of several existing turbulence mode ls for the prediction of film coolant jet in a crossflow. Two-equation mode ls employing k-epsilon and k-omega closures, broadly categorized as high-Re ynolds-number formulations, low-Reynolds-number formulations, DNS-based for mulation, and nonlinear formulations have been used to simulate the flow. I n all, seven different turbulence models have been tested Predictions with different models have been compared with experimental results of Ajersch et al. (1995) and with each other to critically evaluate model performance. T he assessment of models has been done keeping in mind that all models have been formulated for wall-bounded flows and may not be well suited for the j et-in-a-crossflow situation. Close agreement with experimental results was obtained at the jet exit and far downstream of the jet injection region, bu t all models typically overpredicted the magnitude of the velocities in the wake region behind the jet. The present study clearly underscores the defi ciencies of the current models, and demonstrates the need for improvements. [S0889-504X(00)03002-6].