Trajectory Modeling And Numerical Simulation Of Unpowered Carrier Underwater Launching

The underwater launching of unpowered missile,with a high degree of concealment,is adopted as an attacking project from underwater to air.It has attracted much attention in the field of national defense in recent years.In this paper,two general schemes are proposed for the underwater launching of unpowered missile carrier.Using numerical simulation and engineering estimation method,the design and demonstration of the two schemes are carried out.It aims to provide help for overall design,and provide effective reference data for subsequent model experiments,so as to save experimental cost and shorten the experimental period.In the field of engineering estimation,this paper develops a simulation program for underwater launching of unpowered carrier.Quaternion method is also used to solve kinematic equations and dynamic equations of carrier,and which successfully resolves the singularity problem in the large angle of attack simulation.The fluid dynamics of carrier is divided into three parts,and different methods are used to obtain the pre-estimated values of parameters as accurately as possible.Six degree of freedom module and the hydrodynamic module are verified by example,and the satisfactory results are obtained.In the numerical simulation method,the unsteady Reynolds-averaged Navier-Stokes equations and the Standard k-? turbulence model are solved by the finite volume method.The volume of fluid model is applied to capture the air-water interface.The relative motion between carrier and water is handled by the dynamic mesh method.The feasibility and accuracy of the method are verified by the example of submarine hydrodynamic calculation,two-dimensional wedge water entry and three-dimensional plate ditching.Based on the above method,this paper investigates whether the two design schemes meet the design requirements of the effluent speed and posture of carrier,and the effect of the allocation scheme of balancing weight on the sinking of carrier.The flow characteristics of fluid and the kinetic and mechanical characteristic of carrier are also studied during the process of the movement.The results show that tail fin can increase the stability of carrier and in order to reach the designated depth,first counterweight should be thrown as soon as possible.