Numerical Prediction Of Environmental Load For Dynamic Positioning System Of The Ship Platform

With the exploitation of marine resources, the range of human activities extended to the deepwater or ultra deepwater. To ensure the safe operation of the ship platform in the evil marine environment, new requirements of positioning technology should be proposed, including positioning technology. The traditional mooring positioning system is rarely used in the deepwater and ultra deepwater, because the cost of positioning rises with the rise of water depth and the operation is difficult. The Dynamic Positioning Systems (DPS) is not subject to restrictions on water depth, located quickly, operated easily, etc, so the DPS was widely used.The DPS resists against the environmental disturbances with the help of optimal allocation of power on its own. The aim of the system is to control the ship platform on a required position. So it is great significance to the DPS'design and application that accurate prediction of the environmental loads for the ship platform.In the paper, numerical prediction of environment load for the DPS of the ship platform is discussed.(1) The commonly used wind load prediction methods are compared and analyzed, then the goal platform was calculated by Blendermann method. The longitudinal wind load coefficient was modified, and the modified results were compared with the experimental results, which shows the modified method is efficacious(2) The theory of second-order wave of Newman J. N. was deducted briefly, and indicated it is irrational to predict the wave loads of the ship platform with Newman J. N. method by calculated an example at 90°(3) The cross-section of the ship platform was fitted by different shapes, and the transverse current load coefficient was calculated by FLUENT software. The accuracy of the transverse current loads was improved.