Research On The Dynamics And System Optimization Of Large-caliber Artillery Belt Squeezing

Engraving of projectile rotating band is a very important process in the initial interior ballistics of guns.It has an important influence on the safety of the charge and the firing stability,and it is also closely related to the important performance indicators such as barrel life and firing dispersion.The mechanical properties in this process are exceeding complicated problems.It includes the nonlinear mechanical properties of the rotating band material under the action of high temperature and high pressure,the large displacement nonlinear motion of the rotating band and the propellant gas pressure distribution law during rotating band engraving process.For the current stage,most scholars use the classical interior ballistics that use traditional instantaneity assumption to carry out the numerical study of the rotating band engraving process.This paper proposed a one-dimensional two-phase flow interior ballistics as pressure load.Based on the joint simulation of FORTRAN and ABAQUS,the finite element model of the engraving process system coupled with one-dimensional two-phase flow interior ballistics was established.The dynamical response law in the engraving process of the rotating band was obtained through numerical calculations and the effects of engraving system constructions and dynamite filling parameters on the rotating band engraving process were investigated.By establishing the optimization model of large-caliber artillery's rotating band engraving system and using genetic algorithm to solve it,the Pareto optimal solution set of the internal ballistic performance during the process was obtained.Firstly,the composition and structural characteristics of the rotating band engraving system of a large-caliber gun were presented;and the force in the process was analyzed;the calculation method for engraving resistance was introduced,and a theoretical basis for the study of the process was provided.Secondly,for the current research on the process,the classical interior ballistics which can't accurately describe the gas-particle two-phase interaction is adopted.The mathematical model of the one-dimensional two-phase flow interior ballistics for large-caliber artillery launching in this process was established.Mac Cormack numerical method was used to solve this model to get the law of gunpowder combustion,the law of projectile motion,the law of pressure distribution,etc.Thirdly,based on FORTRAN and ABAQUS,the finite element model of the engraving process system coupled with one-dimensional two-phase flow interior ballistics was established,and the nonlinear simulate was performed.The formation process of the rotating band grooves,the elastic-plastic strain of the rotating band,the movement law of the projectile,the dynamical law of engraving resistance was analyzed,the mechanical mechanism of rotating band engraving process was concluded.Through the comparison of part of data with open literatures,the correctness of the simulation models and results were verified.Fourthly,based on the model,the influence law of various factors on engraving process was researched,including the type of twist rifling,the diameter of the lands,the width and the diameter of the rotating band,the structural parameters of charge.And the basis for the internal ballistic performance optimization during the process was provided.Fifthly,aiming at the current situation that the research focuses on the single factor influence mechanism,an integrated design method for the integration of artillery and munitions in the process was proposed.Based on the experimental design method,finite element numerical simulation and approximate model technique,the optimization model of rotating band engraving system of large-caliber artillery was obtained.The genetic algorithm was used to solve the optimization model,and the Pareto optimal solution set of the internal ballistic performance during the process was obtained.