Research On The Launch Dynamics Of A Light Recoilless Gun

The recoilless gun is a special artillery that uses the reaction of the gunpowder gas through the rear nozzle of the gun to eliminate the recoil of the gun and balance the artillery.In order to study the dynamic response of the rifled recoilless gun and the smooth-bore recoilless gun,a comparative analysis was carried out from the aspects of interior ballistic modeling,coupling analysis of projectile and gun,and launch stability.Aiming at the interior ballistic modeling design of recoilless gun,the interior ballistic of rifled gun was established based on the classic interior ballistic equation of recoilless gun.Since the projectile fired by the smooth-bore gun is a turbine empennage projectile,the tail of the projectile is equipped with special structures such as a tail rod,a tail and a turbine,which change the state of airflow in the bore.Therefore,in view of the movement characteristics in the bore,the classic interior ballistic is improved in some degree and the model solution is close to the experimental value after numerical calculation.Recoilless gun is single-soldier weapon.In order to reduce the overall quality of the artillery,the barrel wall is generally thin,so it is necessary to control the pressure in the chamber.By analyzing the influence of the mixed charge ratio on the interior ballistic performance,it is found that the increase in the proportion of thick powder under the same charge can reduce the pressure in the chamber.Therefore,the interior ballistic model of the smooth-bore gun was combined with the genetic algorithm to improve the charge of the artillery.After optimization,the best charge and charge ratio that meet the requirements of tactical indicators were obtained.By establishing the finite element model of the barrel,the temperature field distribution and stress field distribution of the smooth-bore barrel were analyzed.The analysis shows that during the launch process,the temperature of the inner wall of the body tube rises quickly and the temperature is higher,but the temperature rise of the outer wall of the body tube is relatively gentle and the temperature is low.There is no accumulation of temperature,and the temperature of the outer wall of the barrel is within the human body's bearing range;the maximum stress on the barrel is mainly distributed in the barrel part.Under the combined action of the pressure in the chamber and the collision of the projectile,the maximum stress value is not exceed the yield limit of the material.By analyzing the structural characteristics of the tail nozzle of the recoilless gun and combining with aerodynamics,the unbalanced force on the nozzle was deduced,and the solution result is similar to the experiment.In view of the existence of the gap between the centering part of the projectile and the barrel,the contact friction coefficient,the mass eccentricity of the projectile,and the different structure of the barrel bore,the movement of the projectile is uncertain and the movement parameters of the projectile when it exits the muzzle are disturbed.Therefore,based on the free beam vibration theory under the moving load,a dynamic model of the projectile-gun coupling during the launching process of the artillery was established to analyze the movement law of the projectile in the bore.At the same time,based on the analysis results,a neural network proxy model was established for structural optimization design.After optimization,the initial disturbance of the projectile is greatly reduced,which has a certain significance for improving the accuracy of artillery shooting.Aiming at the problem of the stability of recoilless shooting mounted on the light tripod,a virtual prototype of the artillery launching system was established for simulation analysis of different working conditions.The results show that the stability of the smooth-bore gun is better than that of the rifled gun,and the greater the horizontal azimuth angle of fire,the worse the shooting stability of the gun.