Extended Application of a Single Hot-Film Probe for the Measurement of Turbulence in a Flow Without Mean Velocity

摘要

The linear wave theory shows that in relatively deep water outside the breaker zone the motion near the bed due to surface waves is oscillatory. This oscillatory motion establishes an oscillatory wave boundary layer, which can become turbulent under certain wave conditions and bed roughness conditions. The hydrodynamic effect of the turbulent boundary layer has been studied previously in connection with bed load transport under such conditions. The purpose of the study is to investigate the characteristics of the structure of turbulence above the turbulent boundary layer due to an oscillating bed, with a view to predicting suspended load distribution in such a flow field. The method of application of the single hot-film probe to measure the vertical component of turbulent fluctuations in the flow field above the oscillating bottom with no mean motion was described and the results of analysis of the preliminary measurements made by using this method are also presented. (Author)