The Experimental Study Of Wind Speed Scale Of Cylinders In Gravity Similarity

When using the physical model test to study the ocean hydrodynamic problems,the similar gravity criteria are always used.It's undoubtedly appropriate for the study of waves,currents and their interaction with structures.But in the gravity similar system,how would the wind effect be accurately simulated when researching the collective effect of wind + wave,wind + currents and wind + wave + currents.This problem need to be faced firstly and solved when researching these effects.There is no accepted answer to this question so far.In the case of gravity similarity,the correction of the relevant wind speed scale is carried out,so that the action of the wind is similar under gravity similar system.Based on the prototype wind power calculation and the wind tunnel physical model test,the problem of wind speed scale correction under gravity similarity criterion considering the group effect of the cylindrical and square cylinder structures are studied.The factors include turbulence,Reynolds number(wind speed),geometric scale,spacing ratio and other factors.And the influence of these factors to wind speed scale correction factor is also given.The study draws the following conclusions:The wind speed scale does not need to be amended only in the turbulence field conditions.There are several cases:For two cylinders with tandem arrangement:(1)the spacing ratio of-3,1.3 and 8,the prototype wind speed is between 40m/s and 80 m/s and the geometric scale is between 1:100~1:40.(2)the spacing ratio of-1.3,2,3 and 5,the prototype wind speed is between 40m/s and 80 m/s and the geometric scale is 1:80.For circular cylinders arranged side-by-side: the spacing ratioT*=1.7~5,the prototype wind speedV=40~80m/s and the geometric scale?L=1:100~1:40.For square cylinders arranged side-by-side: the spacing ratio T*=1.3~5,the prototype wind speed is 30m/s and the geometric scale?L=1:100~1:60.The wind speed scale need to be amended in uniform field.The correction coefficients of wind speed scale under different conditions are given.