Modeling And Simulation Of Offshore Engineering Vessel Unit Propulsion System

In order to analyze and research on the unit propulsion system of offshore engineering vessel, "SEA OIL 681" was taken as the research object, on which a model of unit propulsion system was built and its simulation was carried out.The mathematical model of this propulsion system includes mechanism mathematical model of diesel, logic model of diesel controller, ship maneuvering mathematical model, propeller mathematical model, as well as 3D virtual scene,3D model of propulsion system,2D visual simulation of models, etc. All the mathematical models have been validated in MATLAB before programming. In this simulation platform, the prototype of diesel model is the advanced turbocharged four-stroke V-type diesel engine, Wartsila 16V32. This diesel model is built via the thermodynamic principles and Volumetric Method that is popular in diesel modeling. The cylinder thermodynamic system, intake and exhaust system, turbocharging system, piston and rod mechanism are included in the diesel model. Its control logic is consistent with the vessel. The propeller mathematical model is created according to the Netherlands B4-55 type propeller map and empirical formulas. Ship motion model, ship and propeller interference model are built according to the parts separate model (MMG) that raised by Ship Manoeuvring Mathematical Model Group, a group of Japan Towing Tank Committee. In order to focus on key point, optimize simulation structure and simplify calculation, the vessel motion model only controls the vessel’s motion in three degrees of freedom-surge, sway and yaw-in the horizontal plane. Hydrodynamic derivative uses the regression formula of Inoue Map regressed by Zhou Zhaoming.As for the simulation platform, it is designed by layer concept in which the models, data, user graphic interface and model manager are distributed to modularize the object and gain a facilitate maintenance. In order to achieve the rich presentation capabilities, the program framework uses the Microsoft WPF (Windows Presentation Foundation) desktop application framework. The 3D models in the simulation platform are built by Autodesk 3ds Max at first. Then this 3D models are processed by Electric Rain ZAM 3D for coordinates, texture, and animation adjustments. Finally, it is exported in XAML (eXtensible Application Markup Language) format that is supported by WPF so that it can be controlled by this simulation program.By creating a more accurate model of propulsion system, this simulation platform can be used to analyze performance of unit propulsion system of vessels, go on manipulation training of unit propulsion system. It can also be used to research control system based on unit propulsion system.