PREDICTION OF TRANSITION REGION IN FLOW OVER THE FLAT PLATES

摘要

A new model has been developed to predict the onset of transition from laminar to turbulent regime and also calculate the transition flow field. In developing the model, we have used the V2F turbulence model to predict the Re_θ and velocity fluctuations, u', at the onset of transition point, extracted from the same available experimental cases over a flat plate for several experimental cases.Then, we have correlated Re_θ as a function of u' at the transition point. This correlation has been used in conjunction with the V2F model to find the onset of transition point. The intermittency model has also been modified to calculate the probability of turbulence regime all over the flow field to improve the eddy viscosity calculated by V2F model. The model has been tested for different flat plate flows and the results compared with experimental data insuring the accuracy of the model. Comparison showed that the model is a powerful tool for prediction of transition onset and also transition region.