SIPS2018 Volume 4. Mamalis Intl. Symp. / Advanced Manufacturing

Editors: | F. Kongoli, A. G. Mamalis, K. Hokamoto |

Publisher: | Flogen Star OUTREACH |

Publication Year: | 2018 |

Pages: | 352 pages |

ISBN: | 978-1-987820-88-1 |

ISSN: | 2291-1227 (Metals and Materials Processing in a Clean Environment Series) |

This paper considers the parameters of motion of the damaging fragmentation elements of an arbitrary shape. The impact velocity of the damaging fragmentation elements is critical for assessing the effectiveness of the ammunition use. The distance from the explosion point at which the fragmentation element still retains damaging properties is also an important factor for estimating the safety of ammunition application as well as effectiveness.

The determination of those two factors demands the analysis of the ballistics of damaging fragmentation elements. The core element affecting the velocity and range of flight of fragmentation elements is their drag coefficient.

There is an approach [1] that is widely used for the consideration of aerodynamic coefficients related to the Reynolds number. However, for the velocities at which the fragmentation elements have damaging properties, the approach mentioned above can provide less important data than the consideration of aerodynamic coefficients related to the Mach number.

In the literature [2-6] there are many papers providing several mathematical descriptions on the relation of drag coefficient of the spherical fragmentation elements to the Mach number, however these functions include physically unexplained gap points. The paper [7] provides the table data on the relation mentioned above, and its precise mathematical description is provided in the paper [8]. Generally, the relation of drag coefficient of fragmentation elements to the Mach number is a stochastic function. This paper provides an analysis of this stochastic function based on the experimental data from [9]. The standard deviation measures of the drag coefficients of fragmentation elements of an arbitrary shape show that for more accurate estimations in future experiments, drag coefficient data collection needs the grouping of fragmentation elements by masses and sizes.

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[8] Baghiyan A.H., Skrynnikov A.A., Voronko O.V., Dorofeyev V.A., Pominov V.N. Analitic Representation of Drag Coefficient of Fragmentation Elements // Ammunition, 2007, No. 1, pp. 15-17.

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