Research On Reynolds Number Effect Of Armor Block Under Long Period Wave

Due to the implementation of China's“Belt and Road”policy,overseas port engineering projects are increasing year by year,most of which are located in the sea dominated by long-period waves.The characteristics of long-period waves are different from general wind waves and short-period waves.Generally,the wave height is not high,the wavelength is longer,and the statistical and spectral characteristics are also obvious,which greatly affects the stability of the breakwater and the wave conditions in the harbor.Rubble mound breakwater is the most commonly used structural form in port engineering.The stability of its armor block under the action of long-period waves has many shortcomings in the calculation of current Chinese standards.For the design wave average period of more than 10 seconds or the design wave height and design For tanks with a wavelength ratio of less than 1/30,the weight of the block should be verified in a model test.For long-period waves,due to the limitation of experimental equipment,the experimental scale is usually smaller,and the experimental Reynolds number effect is more obvious.Therefore,it is very important to find out the Reynolds number effect problem in the physical model test for the model test of the stability of the protective armor block under the action of long-period waves.This paper simulates the physical model test load of the armor block by numerical calculation and analyzes its Reynolds number effect.The single sphere,double-link armor block,and accropode armor block models are simulated respectively,and the Reynolds number effect is analyzed according to the results;the Reynolds number effect of the block under the action of waves is also considered when there is an interaction between the facing blocks.The results show that for the sphere,double-link armor block,and accropode armor block models,the smaller the model scale,the more obvious the Reynolds number effect of the model test of the block model under the action of waves,and the calculated prototype load will be higher than the actual load.The bigger the more.Analyze the relationship between the drag force coefficient and the inertial force coefficient and the Reynolds number.When the Reynolds number decreases,the drag force coefficient increases and the inertial force coefficient decreases.When there is an interaction between the armor blocks,the smaller the scale of the block model,the more obvious the Reynolds number effect.Compared with a single block,the Reynolds number effect is more significant when there is an interaction between blocks.When the Reynolds number decreases,the drag force coefficient increases and the inertial force coefficient decreases.Compared with a single block,the number of C_dand C_m is smaller when there is an interaction between blocks.From the simulation conditions,when the Reynolds number is less than(3-5)×10~4,the structural Reynolds number effect is more significant.When performing physical model tests within this Reynolds number range,the influence of the Reynolds number effect on the results should be considered.Research and revise the stability coefficient of the armor block,which can provide a reference for the calculation of the stable weight of the block.