Influence of the initial velocity of the projectile on the kinematics of the projectile

Abstract

The work uses a mathematical model for determining the frontal air resistance to the movement of the projectile, which based on solving the inverse problem of dynamics. Knowing the flight range at certain angles of aiming given in the firing tables, the functional dependence of the force of the frontal air resistance to the movement of the projectile on its speed and other factors is determined, taking into account the effect on the projectile of its weight and Coriolis force. It has been established that, depending on the aiming angle, the projectile speed during flight can combine stages of movement with supersonic,transonic, subsonic, decreasing or increasing speeds. Therefore, the functional dependence of the frontal drag force is determined for each stage separately.  The influence of the initial velocity and the deviation from the nominal value for the OF-462ZH projectile fired from a 122-mm D-30 howitzer, charge is investigated. Depending on the aiming angle, the projectile speed during flight can combine stages of movement with supersonic,transonic, subsonic, decreasing or increasing speeds. It was found that the displacement values of the coordinates of the zeroing point of the trajectory of the projectile, determined on the basis of the proposed mathematical model, are almost the same in modulus when the initial velocity deviates by +∆V0; the tabular values of the displacements of the trajectory zeroing point, in general, are large in magnitude from the theoretical; the greatest discrepancy between them is achieved at an aiming angle of 45o00’; determination of which of the displacement values, theoretical or tabular, are real, is possible during field tests.