Numerical study of the hydrodynamic properties of a mid-water sensors mounting structure

A single-point Electro-Mechanical(EM) cable subsurface mooring(EMC-SSM) is a subsea structure used in measuring a variety of ocean parameters throughout the water column continuously. A mid-water sensors mounting structure (MWSMS) is an important part of the single-point EMC-SSM and is used to mount a variety of sensors in mid-water column. This paper investigates the hydrodynamic properties of a MWSMS shape. Numerical methods for determining added mass coefficient and drag coefficient on a complex multi-component body are presented. The accuracies of numerical methods are evaluated by comparing with those of superposition methods. It is found that the accuracy of the drag coefficient is improved by about 15% in X direction, and the accuracy of the added mass coefficient is improved by 11.2% and 9% in X and Z direction respectively. These coefficients obtained by numerical methods will be used in simulating the response of a single-point EMC-SSM system.