Drag Analysis of Contractile Water Jet Locomoted Micro AUV in Laminar Fluid

Drag analysis is vital to measure the performance of the autonomous underwater vehicle (AUV) as well as the AUV thruster. Most of the previous drag studies is regarding to the shape and swimming method that contribute to the AUV performance. However, few attention was given on drag which influence the development of thruster. Hence, this research was conducted to analyze the drag of the micro AUV in a laminar fluid flow in order to find the optimum thrust that must be gained by a contractile water jet thruster (CWJT). Besides, these studies also focus on the dynamic pressure and skin friction that forms the total drag which acted on the AUV surface. Drag was measured by using pull technique and simulation technique for AUV speed below 0.5ms. The results show that the recorded drag was between 9.0 x 10N and 1.8 x 10N. The trend line between the simulation data and experimental data has no significant difference and thus it shows that the simulation data were verified. Both results exhibits that the drag increase tremendously regarding to the AUV speed increment.