Accession Number:

AD0854313

Title:

Aerodynamic Spike Experiments on a Sphere in Supersonic Flow.

Descriptive Note:

Technical rept. Jan-Jun 68,

Corporate Author:

AEROSPACE CORP EL SEGUNDO CALIF LAB OPERATIONS

Personal Author(s):

Report Date:

1969-03-31

Pagination or Media Count:

26.0

Abstract:

In order to estimate the potential usefulness of an aerospike for reduction of reentry observables, preliminary tests were conducted to determine the effective body shape created by an aerodynamic spike on a hemisphere in supersonic flow. The tests were performed in a 200-kW air arc tunnel on a 1-in.-diam sphere with an internal forward-facing supersonic nozzle through which nitrous oxide gas was injected. The wind tunnel flow Mach number was 4.5 and the aerospike initial Mach number was 2.2. The aerospike nozzle exit diameter was 0.104 in. The mixing region of nitrous oxide gas and air was visible due to chemiluminescence, permitting photographic determination of the approximate effective body shape. Three characteristic regimes of aerospike behavior were observed, in which the effective body shape ahead of the hemisphere progressed from nearly-conical to nearly spherical. The maximum aerospike length in the nearly-conical body regime was one-half of the sphere diameter this length was strongly dependent upon angle of attack beyond 3.5-deg angle of attack. Author

Subject Categories:

  • Guided Missile Reentry Vehicles
  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE