摘要
Velocity vertical profiles in the bottom boundary layer are important to understand the oceanic circulation.The logarithmic vertical profile,u=A ln z+B,is the universal profile for the horizontal velocity in the boundary layer,in which two coefficients(A and B)need to be determined.The two coefficients are the functions of the friction velocity(u_(*))and the roughness length(z_(0)),and they are calculated using u_(*)and z_(0).However,the measurement of u_(*)and z_(0) is a challenge.In the present study,an approach is developed to estimate the two coefficients(A and B)by using a series of fl ume laboratory experiments with fl at boundary and regularly distributed cylinders as the rough boundaries.An acoustic doppler velocimeter(ADV)is used to measure the velocity vertical profiles of the steady flow.Using the measured velocity data,the regressed logarithmic profiles are obtained.Based on the series of the A and B values,the mathematical formula for A and B are statistically established as the function of the cylinder height,inflow velocity,and the water depth,which avoids the measurement of the friction velocity and the roughness length.
基金
Supported by the National Key Research and Development Program of China(Nos.2017YFA0604100,2016YFA0601803,2016YFC1401407)
the National Natural Science Foundation of China(Nos.41490643,41706008)
the Guangdong Basic and Applied Basic Research Foundation(No.2019A1515110840)
the Innovation Group Project of Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)(No.311020004)
the Key Program of Marine Economy Development(Six Marine Industries)Special Foundation of Department of Natural Resources of Guangdong Province(No.GDNRC[2020]049)。
