Accession Number : ADA139107

Title :   Investigation of Aerodynamics of Non Axisymmetric Projectiles.

Descriptive Note : Final rept. 1 Mar 82-30 Nov 83,


Personal Author(s) : Zakkay,V ; Agnone,A ; Prakasam,B

PDF Url : ADA139107

Report Date : Jan 1984

Pagination or Media Count : 39

Abstract : An experimental and analytical investigation of boattail projectile drag reduction was performed. The experiments were conducted at Mach 6.3, and at a free stream Reynolds number based on the cylinder diameter Re = 3.7 million. Heat transfer measurements were also performed, and the results indicate that the flow field was predominently laminar upstream of the boattail. The results of the analysis indicate that inviscid codes may be used to provide guidelines for possible three-dimensional geometric configurations for the reduction in the drag. The discrepancies between experimental results and theoretical predictions are significant towards the end. Both the experimental and theoretical results indicate that the triangular boattail yields the largest drag reduction. Since the predominant drag of the boattail is the base drag, it is essential for future research that accurate measurements be performed in the base region of the model in order to have a better comparison between the various boattail configurations.

Descriptors :   *Boattail afterbodies, *Projectiles, Aerodynamic configurations, Flow fields, Drag reduction, Hypersonic characteristics, Heat transfer, Surface temperature, Heat flux, Pressure distribution, Three dimensional flow, Finite difference theory, Algorithms, Conical bodies, Triangles, Base flow, Experimental data, Computerized simulation

Subject Categories : Ammunition and Explosives
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE