Simulation Research On Steady-state Characteristics Of Vehicle Body When Shooting Amphibious Amphibious Artillery On The Water

In offshore defense Combat,amphibious landing operations shoulders an indispensable role,but amphibious artillery with its unique advantages of high assault and strong assault force,this makes amphibious artillery one of the protagonists in offshore and beach landing operations.Amphibious artillery,in addition to the requirements of rapidity and flexibility,it must also have good water shooting ability and water shooting stability,which will greatly improve survivability and can play a more efficient role in protecting fleet safety and landing operations.This paper mainly combines CFD technology to establish a simulation model of amphibious artillery shooting on the water,and then conducts a simulation study on the stability characteristics of the vehicle body when the amphibious artillery is shooting on the water.The main research contents and results are as follows:This paper takes a certain type of amphibious artillery as the research object,and systematically analyzes the force of the vehicle body in the water and the motion state of the vehicle body in the water when the amphibious artillery is shooting.A mathematical model of amphibious artillery shooting on the water is established,and the numerical method for solving the model is described in detail.Based on the Fluent software,the VOF method is used to deal with the free liquid surface,combined with the SST k-ε model,by solving the Navier-stokes equation,the 2D with three degrees of freedom transient numerical simulation of the amphibious artillery when the amphibious artillery is stationary in still water and shooting at different shooting angles.Three degrees of freedom movement including the surge,heave and pitch of the vehicle body is obtained.The change of the vehicle body’s movement posture when the amphibious artillery is shooting at a shooting angle of 30° is analyzed in detail,and the influence of different shooting angles on the stability of the vehicle body is obtained.Subsequently,on the basis of the previous,a numerical wave pool is established to study the motion posture of the vehicle body when the amphibious artillery is shooting in waves.The numerical simulation and calculation are carried out on the three degrees of freedom movement of the vehicle body when the amphibious artillery is shooting at a speed of 0 and a speed of some in the secondary sea conditions,and the influence regularity of the stability characteristics of the vehicle body when shooting at different shooting angles is obtained.Finally,the resistance characteristics and lift characteristics of hydrofoil at the bottom of the vehicle body are studied and analyzed when the amphibious artillery is shooting in still water,and based on the orthogonal analysis method and computational fluid dynamics（CFD）theory such as RNAS equation and SST turbulence model,the two-dimensional numerical simulation of hydrofoil at the bottom of the vehicle body is carried out.The resistance characteristics and lift characteristics of hydrofoil at the bottom of the vehicle body under different angles of attack and different relative immersion depths are studied and analyzed.Finally,the influence regularity of the angle of attack of the vehicle body and the relative immersion depth on the stability of the vehicle body is obtained,which is a useful and in-depth exploration for the design and optimization of amphibious artillery.