Turbulence characteristics of flow region over a series of 2-D dune shaped structures |
| |
Authors: | Satya P Ojha BS Mazumder |
| |
Institution: | Fluvial Mechanics Laboratory, Physics and Earth Sciences Division, Indian Statistical Institute, Calcutta 700 108, India |
| |
Abstract: | This paper addresses the development of a flow region associated with turbulence and stress characteristics over a series of 2-D asymmetric dunes placed successively at the flume surface. Experiments were conducted over twelve asymmetric dunes of mean length 32 cm, crest height 3 cm and the dune width almost as wide as width of the flume, using 3-D Micro-ADV at the Indian Statistical Institute, Calcutta. The variations of turbulence statistics along the flow affected by the wavy bottom roughness have been studied. Quadrant decomposition of the instantaneous Reynolds shear stress has been adopted to calculate the contribution of ejection and sweeping events in shear stress generation. The relative dominance of two events are found to contribute in a cyclic manner (spatially) in the near bed region, whereas such phenomenon seems to be disappeared towards the main flow. |
| |
Keywords: | Turbulent boundary layer Dunes Flow separation Reynolds stress ADV Conditional statistics |
本文献已被 ScienceDirect 等数据库收录! |
|