Hydrodynamic Performance Analysis In The Process Of The Underwater Vehicle Recovery Via Submarine

With the development of ocean research field,it is more important to explore the complicated ocean situation than ever before.The Autonomous Underwater Vehicle(AUV)is a special operated platform.It meets the urgent and increasing needs.Also,it is facing huge challenges.Furthermore as the AUV develops rapidly,there will be more underwater tasks for AUV.The AUV meets specific mission requirements in the water.It often needs to interact with large submarines such as energy supplement,data exchange etc.In addition,during the recovery process,due to the complex flow field which causes a large hydrodynamic interference,it is essential to simulate the hydrodynamic performance and maneuverability of the AUV and Submarine precisely in this complex disturbed flow field.As a consequence,it is significant to calculate the hydrodynamic performance in this sophisticated flow field quickly and accurately in order to plan a better recovery path.This paper adopted the method of Computational Fluid Dynamics(CFD).It used the STARCCM+ software to calculate the hydrodynamic performance of the full appended SUBOFF submarine model with the complex flow field.Moreover,this article simulated the hydrodynamic interference in the process of submarine piggyback recovery.The main methods were as follows:Firstly,this paper was based on the CFD technology.The STARCCM+ software was used to calculate the resistance values of the spheroid which located submerged domain in different inlet velocity simulation.Then this article compared the results with the experimental values.It was proved that the SST k-? turbulence model,meanwhile,using the trimmed mesh can accurately calculate the resistance value of the spheroid.Furthermore,this paper predicted the hydrodynamic performance of SUBOFF with complex flow field,and compared with the experimental values.Secondly,this article established the SUBOFF submarine dock recovery model.Then it used the overlapping grid method to calculate the hydrodynamic interference of a AUV which moves linearly towards the recovery device.This paper compared the results of two different kinds of motion including the uniform linear motion and the uniform deceleration linear motion.The results confirmed that the force of AUV which moved uniform linearly was more complicated.This method went against the recovery work.On the contrary the force of the uniformly retarded motion was relatively flat,which was more convenient for recovery.Finally,this article established the model of the open-shelf recovery device and assumed two recovery paths.The overlapping grid technique in STARCCM+ software was used to simulate the hydrodynamic performance of an AUV which follows the given path closing to the SUBOFF submarine model.It also researched the influence on the flow field around the AUV caused by the submarine.As a conclusion,the interference of AUV along the path of the sine curve movement was smaller.This path could reduce the risk of the recovery work.