An experimental study of turbulence in a heterogeneous channel

作者：Jesson Michael^*; Sterling Mark; Bridgeman John

来源：Proceedings of the Institution of Civil Engineers-Water Management, 2013, 166(1): 16-26.

DOI：10.1680/wama.11.00025

This paper examines the velocity field in an idealised heterogeneous open channel during normal flow conditions, corresponding to two different subcritical flow conditions (discharges of 0.040 m(3)/s and 0.056 m(3)/s, with corresponding Froude numbers 0.51 and 0.57). The bed of the channel is formed of two full-length, longitudinal strips of equal width, a smooth section constructed from polyvinyl chloride and a rough section constructed from gravel (d(72) = 10 mm). The results indicate that the turbulence appears to propagate vertically from the rough bed and horizontally over the rough-smooth boundary. There is also evidence to suggest that the turbulent momentum transfer is maximised at the rough-smooth boundary. Secondary flow structures are seen to exist due to the rough-smooth boundary and provide another mechanism for momentum transfer. These transfer mechanisms are important in understanding the effect of a heterogeneous channel bed on open-channel flow.

• 出版日期2013-1