Author(s): Ichiro Kimura; Takashi Hosoda
Linked Author(s): Ichiro Kimura
Keywords: 2D mixing layer; K-H instability; Non-linear turbulence model; CFD
Abstract: This paper describes application of modified depth-averaged numerical model to 2D mixing shear layers in open channels with two different depths. The flow around a mixing layer is characterized by coherent structures with vortex formations due to the K-H instability. Since the dominant flow pattern has basically plane 2D structure in shallow mixing layer in open channels, the plane 2D depth-averaged model seems to be applicable to some extent. In this paper, the depth-averaged 2D open channel equations with refined expression for Reynolds stresses are applied to the plane shallow mixing layer. The turbulence model is tuned within the frame of simple 0-equation model. Attention is focused on effects of depth to the development and attenuation of coherent structures. Computations are performed under the conditions of the laboratory tests with two different depths performed by Uijttewaal & Booij (2000). The present numerical model could reasonably predict fundamental aspects of turbulence flow features under different depths.