| Aiming at the problem that the traditional small-caliber gun barrel structure is too large and the recoil force does not match the unmanned combat platform,the structural parameters of the barrel are adjusted,and a compound recoil reduction scheme is proposed,which combines the high-efficiency muzzle brake,nozzle airflow reverse thrust device and buffer device.In order to explore the recoil reduction efficiency of the complex recoil reduction device,the movement process of the gun and the stress and temperature changes of the key components during the firing of the gun,the multi-software numerical simulation of the complex recoil reduction device is of great significance.The work content of this paper is as follows:(1)Determination of structural parameters of compound recoil reduction device and calculation of internal ballisticsIn the second chapter,the position parameters of the air guide hole on the gun barrel are adjusted according to the experiment,and the structure of the muzzle brake is designed to match the muzzle projectile muzzle velocity and the efficiency of the recoil reduction device.Based on the single stiffness ring buffer spring,a variable stiffness buffer device is designed.Considering the outflow of gunpowder gas when the air guide hole is opened,the corresponding variable mass interior ballistic equation is established,which provides a theoretical basis for subsequent research.(2)Numerical simulation of flow field of air guiding recoil device and muzzle brakeIn the third chapter,fluent software is used to simulate the air guided recoil device and calculate its recoil kinetic energy efficiency by combining three-dimensional unsteady N-S equation and two-dimensional unsteady Euler equation.The motion of the projectile exit is simulated through the two-dimensional dynamic layered grid,the force of the two-dimensional equivalent muzzle brake is calculated,and the 1/4 muzzle brake model is used to check.Finally,the recoil kinetic energy efficiency and impulse change of the muzzle brake are calculated.(3)Analysis of gun launching dynamicsIn the fourth chapter,the calculation model of Gun Launch Dynamics is established by using Cro/E software,and the model is imported into Adams through the data interface between the software.The multi rigid body dynamic model of Gun Launch is established and the corresponding loads and constraints are imposed.Six schemes are preliminarily arranged according to the design idea,The movement of the gun body during firing with the composite recoil reduction device is studied.Based on the single stiffness ring buffer spring,the dynamic analysis and optimization of the variable stiffness buffer device are carried out,and the best anti recoil scheme is determined.(4)Analysis of strength and temperature field of key components of artilleryIn view of the large thrust generated by the nozzle when the gun is launched,the finite element models of the nozzle and support frame in the gun barrel and recoil recoil reduction device are established in the fifth chapter,and the maximum stress is simulated in Abaqus.The simulation results show that the maximum stress of the above components does not exceed the yield limit of gun steel.The analysis of the temperature field of the nozzle in the gun barrel and recoil recoil reduction device shows that the temperature rise of the inner wall of the barrel and nozzle is fast and high,and the temperature rise of the outer wall is mild and low. |
