Accession Number : AD1011548


Title :   Shape Factor Modeling and Simulation


Descriptive Note : Technical Report,01 Nov 2015,31 Mar 2016


Corporate Author : ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD ABERDEEN PROVING GROUND United States


Personal Author(s) : Saucier, Richard


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/1011548.pdf


Report Date : 01 Jun 2016


Pagination or Media Count : 100


Abstract : The dimensionless shape factor, which relates the projected area of a fragment to its mass per unit density, plays a fundamental role in ballistic penetration. Explicit analytical formulas are given for the shape factor distributions of some common shapes with random orientations. It is straightforward to simulate these shape factor distributions with computer code, and we verify that the simulations match the plots from the analytical formulas. However, none of the simple common shapes provides an adequate simulation model for natural fragments. We show that natural fragment data can be fit with a lognormal distribution, which then provides a simulation model for Monte Carlo sampling. Laser scans of fragments can also be used to compute the fragment shape factor from any viewpoint; various methods of achieving a uniform spherical distribution are described. Finally, we show that it is possible to realize each fragment as either a yawed cylinder or a cuboid with a pitch, yaw, and roll. Thus, we have a procedure for generating all the input variables required to run THOR or FATEPEN with natural fragments.


Descriptors :   ballistics , ammunition fragments , shape , computational modeling , mathematical models


Subject Categories : Ammunition and Explosives
      Ballistics
      Operations Research


Distribution Statement : APPROVED FOR PUBLIC RELEASE