Shape Optimization Design Of50Kilograms Autonomous Underwater Vehicle Based On Hydraulic Characteristics

The50kg Autonomous Underwater Vehicle (small AUV), because of itshigh speed, high maneuverability and low cost, gradually attracting people’sattention, plays an important role in both military application and the development ofmarine resources. Because AUV can only carry limit energy, so how to improveenergy efficient has been taken as the criterion to evaluate the performance of AUV.Research indicates that reducing the sailing resistance is an important method toimprove energy efficiency. Therefore, the shape optimization of AUV has become asignificant subject in AUV research. This paper aims to designing a low-resistanceautonomous underwater vehicle and developing an effective method to decrease theresistance of AUV under the premise of a certain amount of displacement. Aroundthe target, the following aspects will be researched.(1) According to the basic data the subject provides, the low-drag shape of AUVhas been designed, under the displacement constant. It mainly includes the selectionof streamline shape of the axisymmetric main body, the analysis of hydrodynamicperformance of the main body, the selection and design of the rudder, as well as theanalysis of hydrodynamic performance of the whole prototype.(2) Based on the prototype shape of AUV and the multi-objective geneticoptimization algorithm, the optimum shape of AUV has been obtained by usingmultidisciplinary optimization software Isight. It mainly includes the parametricdesign AUV model, the integration and automation of hydrodynamic calculationbefore and after process of AUV, the analysis and processing of optimizationalgorithm for calculation results, the hydrodynamic performance analysis andcomparison between the prototype and after optimization. Under the premise ofguaranteed displacement, the optimum hydrodynamic shape of autonomousunderwater vehicle can provides references for future design.(3) The structure of AUV system is designed and processed with the modularmethod, on the basis of the optimized AUV shape. It mainly includes the design of pressure hull, the connection and sealing between the cabins, the design of the devicefor direction adjusting, the design of propeller and the selection of main motor inpropulsion system, etc. It provides references for the design and development of thesame type AUV.(4) Most of the hydrodynamic coefficients of autonomous underwater vehicle,including acceleration coefficient, velocity coefficient, rudder angle coefficient andangle velocity coefficient, are obtained by the method of approximate calculationspecifically using the equivalent ellipsoid and the equivalent flat-plate theory. Itprovides references for the analysis of the AUV’s maneuverability and its underwatertests.