Dynamic behaviors of autonomous underwater vehicles considering lateral flow

Dynamic behaviors of AUV show a complex six-degrees of freedom (6-DOF) motion. They have great influence on the task precision and are influenced by uncertain marine environment parameters, in which influence of the lateral flow is one of the most significant. In this paper, dynamic behaviors of AUV in lateral flow are investigated using the CFD-based numerical method. Pressure distribution on the surface of the AUV, trajectory of center of gravity and attitude angle of the AUV are obtained and presented with different speeds and directions of lateral flow. The AUV has a steady yaw motion in definite time by the effect of lateral flow. In addition, four different layouts of the tail fins are discussed for the sake of improving ability of resisting the lateral flow. Results shows that the AUV with X-45 ° tail fins can keep better motion performance than others do. The present investigation provides a convenient and effective method to predict the Dynamic behaviors of AUV in complex marine environment and provide theoretical guidance in design stage.