Determination of the magnitude of the frontal air resistance of the bullet, released from the machine guns PK, PKB, PKS and PKT

Authors

  • L. D. Velychko Національна академія сухопутних військ імені гетьмана Петра Сагайдачного, Львів, кандидат фізико-математичних наук, доцент, професор кафедри Інженерної механіки (ОТІВ), Ukraine
  • I. V. Gorchynskiy Національна академія сухопутних військ імені гетьмана Петра Сагайдачного, Львів, начальник факультету підготовки спеціалістів бойового (оперативного) забезпечення, Ukraine

DOI:

https://doi.org/10.33577/2312-4458.18.2018.26-31

Keywords:

bullet movement dynamics, strength of frontal air resistance, kinematic parameters

Abstract

In a majority of works devoted to the research of the exterior ballistics of the bullet movement and missiles the rate of the missile’s form and the reference function of the frontal air is used. However, the obtained on this ground theoretical results not always qualitatively and quantitively coincided with experimental. In the work of authors an alternate approach to the study of the dynamics of the bullets and missiles movement is considered. It is widely thought that the scalar force of the frontal air resistance of the bullet movement depends on the following characteristics: its aerodynamics rate; the greatest cross-section area plane surface vertical to the velocity attitude; its movement rate; air density and the speed of sound in the air. Although it has different values of certain coefficients in cases when the bullet is moved with supersonic and subsonic velocities. Using the law of dynamics – the system of differential equation is obtained, which describe the bullet movement in the air. To determine the certain coefficients of the frontal air resistance value function we should solve the inverse problem of the particle dynamics, taking into consideration the results of the experimental investigations. Solution of the differential equation system is obtained by a numerical method and the coefficients’ value is defined by trial and error method. As an example, the bullet movement from the machine guns such as PK, PKB, PKS and PKT. The functional dependency of the bullet movement frontal air resistance value has been obtained from its velocity and the respective diagram has been created. The received theoretical values of the bullet’s velocity on certain distances were different from the results of experimental measurements within limits of less than one percent. Knowledge of the law of the value change of the frontal air resistance on the bullet movement from its velocity, air density, and speed of sound in the air allows defining the influence of change of these values on the traveltime parameters of the bullet movement. At the same time we can investigate the influence of the change of the muzzle velocity of the bullet, angle of elevation, velocity and direction of the wind on the exterior ballistics of the bullet movement. As an illustration the influence of the angle of position on the traveltime characteristics has been investigated.

References

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Published

2018-10-22

How to Cite

Velychko, L. D., & Gorchynskiy, I. V. (2018). Determination of the magnitude of the frontal air resistance of the bullet, released from the machine guns PK, PKB, PKS and PKT. Military Technical Collection, (18), 26–31. https://doi.org/10.33577/2312-4458.18.2018.26-31

Issue

Section

COMBAT EMPLOYMENT OF MILITARY EQUIPMENT