Study Of Simulating Separated Flow From Cylinder Structures In Ocean Engineer Using Discrete Vortex Method

Cylinder and cylinders are the most common structures among ocean engineering field,simulating the separate flow from cylinder structure induced by viscosity correctly is also a hot and difficult problem in hydrodynamics.Basing on the Discrete Vortex Method,we compute the hydrodynamic coefficients and flow structures of uniform flow past circular cylinder,and the comparison with experiment shows good agreement in Strouhal number,drag coefficient,pressure distribution and velocity field within the scope of application firstly determined.After that,we expand this method to be available for multi objects.Taking flow past cylinders arranged in tandem and side by side as examples,we still compute the hydrodynamic coefficients and flow structures and compared with experiments.Finally we find,for cylinders arranged side by side,the expanded method successfully simulate flow structures,Strouhal number,lift coefficient and pressure distribution when T/D ? 3.0;While for cylinders arranged in tandem,only drag coefficient and the pressure distribution of upstream cylinder agree well with experiment when 1.3?L/D?3.5,and other results just agree in trend partly.This paper has slightly important significance in ocean engineering field,for it expands the Discrete Vortex Method to multi objects,and enlarges the scope of application of this method.