Description: The values of the kinematic parameters of projectiles motion in the air depends on deterministic (form of projectile, its mass, temperature of air and charge, atmospheric pressure, derivation) and nondeterministic (muzzle velocity, magnitude and direction of wind velocity) values. During the projectiles movement, its weight, frontal air resistance force, lifting force, Magnus and Coriolis forces act on it. However, its weight and the force of frontal air resistance have a determining influence on the dynamics of the projectile's motion. In the article it is investigated proposed by the authors the mathematical model of determining the functional dependence of the air resistance force of the projectile movement on its velocity, mass and caliber, geometrical characteristics, temperature and density of air, atmospheric pressure, speed of sound in air. It is considered in the paper that the air temperature and atmospheric pressure depend on the height of the projectile flight. The functional dependence, although it has the same view when the projectile moves with supersonic or subsonic speeds, but differs in the values of certain coefficients. Determination of the values of these coefficients at supersonic and subsonic projectile velocities is carried out by the method of successive approximations, solving the inverse dynamics problem. The experimental results are used for this purpose. Using this dependence, it is possible to determine the magnitudes of the correction due to the effect of changing the above values on the kinematic parameters of the projectile movement, as well as their dependence on muzzle velocity, magnitude of aiming angle, wind speed, and more. The proposed mathematical model of determining of the frontal air resistance force to the projectiles movement makes it possible to determine the aiming angle taking into account the set of interrelated deterministic and nondeterministic values and when firing at a greater distance than specified in the firing tables.
Keywords: artillery, external ballistics of projectiles, frontal air resistance force, temperature of the air and of the charge
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