Application of thermal shear stress gauge in study on wave-current dynamics

The movement of sediment at estuary and coast is directly restricted by the bed shear stress. Therefore, the basic research on the influence of the bed shear stress on the sediment movement is important. However, there is no available method for measuring and computing the bed shear stress under a complicated dynamic condition like the wave current. This paper conducts the measurement and test research on the bed shear stress in a long launder of direct current by the new thermal shearometer based on micro-nanotechnology. As the research results show, the thermal shearometer has high response frequency and strong stability. The measuring result reflects the basic law of the bed shear stress with the wave and wave-current effect, and confirms that the method of measuring bed shear stress under wave-current condition with the thermal shearometer is feasible. Meanwhile, a preliminary method to compute the shear stress compounded by wave-current is put forward. It benefits further research on the basic theory of the sediment movement with complicated dynamic effects.