The Hydrodynamic Performance Calculation And Motion Simulation Of An AUV With Appendages

With further development of marine resources and the needs of military, the AUV has attracted more and more attention in the field of military and scientific applications. Because of the functions of environmental and biological monitoring, hydrographic surveys, scientific sampling, undersea search and mining, AUV become an indispensable tool in underwater operations. Owing to small-AUV's characteristics of small volume, good maneuverability, potential applicational ability and high quality-price-ratio, the research of it has been becoming the focus now.According to the requirements of tasks, some additional equipment should be carried on the body of mini-AUV, which can be regarded as appendages. Generally, designers should take more attention on the influence on hydrodynamic performance and maneuverability performance of mini-AUV after equipping appendages. Accurate motion simulation can predict the motion and maneuverability performance of the AUV with appendages, at the same time, it can reduce the cost of experiments in sea or lake. Therefore, it has great significance to build the AUV's motion simulation system.The research object of the thesis is a small-AUV developed by Harbin Engineering University. Firstly, according to the theory of CFD, Numerical models were established for the AUV with appendages and without appendages, by which their hydrodynamic performance was simulated. The main hydrodynamic coefficients were computed. Resistance performance and the oblique sailing performance of the AUV with appendages were compared with the AUV without appendages, and the influence of appendages on AUV's hydrodynamic performance was analyzed. Secondly, The AUV mode maneuvering performance experiment was conducted. The hydrodynamic coefficients of the AUV with appendages were obtained. The calculated results were compared with experimental data. Finally, the general motion equation in six degrees of freedom was constructed. The forces and moments in the equation were analyzed. The main component of external forces and their solution method were obtained and thereby the motion simulation system of AUV was built. The motion performance and maneuvering performance of AUV with appendages and AUV without appendages were compared and analyzed after typical movement simulation.