The comparison between numerical simulation and water channel experiment on an Mi-zi artificial reef

Abstract

The flow changing around the artificial reef is the fundament of its physical effect.So far,using 3D numerical calculation to study the flow around the artificial reef is a tentative research,so this paper compared the water channel experiment with the numerical calculation to prove its accuracy.Using the Large Eddy Simulation(LES),a method of Computational Fluid Dynamics,this paper simulated the flow around a Mi-zi type artificial reef(dimension compared with actual reef is 1∶10)under a steady initial coming flow.Also,the water channel experiment with the same size as the numerical model is set to prove the feasibility of the numerical simulation.This paper compared the flow from x,y and z,three directions,under six different velocities of the coming flow,0.2 m/s,0.4 m/s,0.6 m/s,0.8 m/s,1.0 m/s and 1.2 m/s.The result showed,about 80% of the velocity on the measured points by numerical simulation are consistent with the results measured by water channel experiment.Also,the discrepant points mainly located on the hatch of the top of the reef.And this position was difficult to measure because of the strong flow changing so that it was allowed to be variant.Therefore,under the overall comparison of results,this three-dimensional numerical simulation can replace the water channel experiment and be applied in the simulation of the same size as the actual artificial reef in the sea area to do the further research of the flow around the artificial reefs more clearly.At the same time,we can use this method to build the artificial reef models to study the flow around the artificial reef with different structures or a set of some artificial reefs,then we can optimize the construction of artificial reefs.