Accession Number:

ADA093301

Title:

Wind Tunnel Wall Interference.

Descriptive Note:

Interim rept. 1 Apr 79-31 May 80,

Corporate Author:

PRINCETON UNIV NJ DEPT OF MECHANICAL AND AEROSPACE ENGINEERING

Personal Author(s):

Report Date:

1980-11-01

Pagination or Media Count:

26.0

Abstract:

The previous analysis of the aerodynamics of an isolated slender slot in a wall has been extended to include the effect of a streamwise pressure gradient. For certain slot planforms, an analytical solution is available for the case of a linear pressure gradient. The effect of aerodynamic interference for a single infinite row of slots was also studied. Solutions were obtained numerically for various Mach numbers, slot spacings, and aspect ratios. The effect of interaction between slots was to increase the slot flow rate for a given pressure differential. A wavy wall problem was posed to study the proper method of obtaining an average wall boundary condition given the behavior of individual holes or performations. This problem contains all the important physics and allows the basic parameters to be controlled in such a way that the important efforts can be clearly identified. Due to computational difficulties, the solution is being reformulated in a more efficient and useful form. However, preliminary calculations with the original approach did show that the boundary condition should be constructed differently for subsonic and supersonic flows, and that there are effects of pressure gradient and hole location become apparent as the pressure field wavelength is decreased. Some work was also done on isolated slot aerodynamics with large free surface displacement and on the compliant wall wind tunnel concept. Author

Subject Categories:

  • Test Facilities, Equipment and Methods
  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE