Accession Number:

ADA046178

Title:

Calculations of Some Unsteady Transonic Flows About the NACA 64A006 and 64A010 Airfoils

Descriptive Note:

Final rept. Nov 1975-Apr 1977

Corporate Author:

GENERAL DYNAMICS SAN DIEGO CA CONVAIR DIV

Personal Author(s):

Report Date:

1977-07-01

Pagination or Media Count:

98.0

Abstract:

Unsteady transonic flows over airfoils were calculated using a program based on the unsteady Euler equations. The approximate numerical solutions were obtained using an explicit Lax-Wendroff difference scheme. Calculations were made for the 64A006 airfoil at zero angle-of-attack in flows with Mach number 0.822, 0.854 and 0.875. Three unsteady flows caused by a quarter-chord flap oscillating with an amplitude on the order of one degree at specific reduced frequencies k omega CU sub infinity near 0.4 were analyzed. The results were compared with other available calculations and the experimental data of Tijdeman. Responses for an airfoil in a ventilated-wall wind tunnel rather than in a free-stream were also calculated. Exploratory study of the changes to be expected with a weakened shock an attempt to simulate a main effect of the interaction of the shock with airfoil boundary layer was done for one case at Mach number 0.875. Oscillatory flows over the 64A010 airfoil at zero angle-of-attack in a Mach 0.80 stream were also calculated. Plunging motion at reduced frequency 0.4 and pitching motions at reduced frequencies 0.4 and 0.5 were calculated.

Subject Categories:

  • Aircraft
  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE