NUMERICAL SIMULATION OF THE CONFLUENCE FLOW BY USING k-ε MODELS

Abstract

The two-dimensional T-type confluence flow is numerically simulated by using k-ε turbulence models. It is found that standard K-ε turbulence model reveals severe discrepancies in predicting the confluence flow which is characterized by a large recirculating region. To analyze the reasons of the poor prediction, further studies are conducted by means of the low-Rynolds number version of k-ε model and an improved k-ε model proposed by Hanjalic and Launder for decelerated flows. By comparing the numerical results with the experimental results, it is understood that the wall functions used in the standard k-ε turbulence model and the inaccurate modeling of ε-equation are two main reasons for the poor predictions. Finally, some suggestions are proposed for the numerical simulations of the confluence flow.