Optimum Projectile Shape for Improved Ammunition
Abstract
A study is made to determine the optimum shape of an artillery shell used to deliver improved ammunition. The optimum shape here is the one that minimizes the dead mass of the shell for a given payload; equivalently the problem is to minimize the surface of a shell with specified volume and total drag coefficient. Linear aerodynamics and several simplifying assumptions are used in stating the drag coefficient dependence on body shape and flight parameters. Restricting the scope of the problem to specific families of curves greatly simplifies the calculations and yet provides valuable guidance in determining optimum shapes; in particular, cone-cylinders and parabolic tangent- ogives are studied. Diagrams are presented showing the dependence of surface area, for unit volume, on the parameters delta (nose thickness-ratio) and k (nose percentage of projectile length). It is found that optimum shapes do not have large length-to-diameter ratios and are nearly independent of Mach number in supersonic flight.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1972
- Accession Number
- AD0906481
Entities
People
- Joseph H. Spurk
- Nathan Gerber
Organizations
- Ballistic Research Laboratory