Influenceof the mass of the projectile on its dynamic

Abstract

As a result of polygon studies, a discrete dependence between aiming angles and horizontal flight ranges of projectiles for a certain type of weapon was obtained. By combining the use of this dependence and the method of the inverse problem of mechanics, the functional dependence of the frontal air resistance force of the moving projectile on its speed, deterministic and nondeterministic factors is determined. On the basis of the second law of dynamics, a system of differential equations is obtained, which describes the movement of the projectile under the influence of the force of frontal resistance, the weight of the projectile, and the Coriolis force. As an example, we consider the dynamics of the OF-462Zh projectile fired from a 122-mm D-30 howitzer with a reduced charge. Its initial speed is supersonic and equal to Vo=565 м/s. In this case, depending on the aiming angle, during the flight of the projectile, its speed can change from supersonic to subsonic or even subsonic.
 Since the mass of the projectile is mostly different from the nominal one, the effect of the change in the projectile mass on the flight range of the projectile and the kinematic parameters of the movement is investigated in the paper. It was established that at small aiming angles, a projectile with a smaller mass flies farther than a projectile with a nominal mass and its final speed is greater than the speed of a projectile with a nominal mass. However, if the aiming angle increases, the flight range of such a projectile is less than the flight range of a projectile with a nominal mass, and the final speed is less than the speed of a projectile with a nominal mass. The opposite picture is observed if the mass of the projectile is greater than the nominal one. In this case, at small aiming angles, the flight range of the projectile is less than the flight range of a projectile with a nominal mass, and its final speed is also less than the final speed of a projectile with a nominal mass. When the aiming angle increases, the flight range of a projectile with a larger mass is greater than the flight range of a projectile with a nominal mass, and its final speed is greater than the final speed of a projectile with a nominal mass.