Accession Number : AD0673896

Title :   RESEARCH ON HYPERSONIC FLOW OF BLUNT DELTA WINGS. PART II. GAP EFFECTS OF A BLUNT SLAB DELTA WING AT MODERATE SUPERSONIC AND HYPERSONIC SPEEDS.

Descriptive Note : Final rept. Nov 66-Jan 68,

Corporate Author : ARA INC WEST COVINA CALIF

Personal Author(s) : Mazelsky,Bernard ; Chao,Chia-Chun

Report Date : FEB 1968

Pagination or Media Count : 86

Abstract : It was found that the maximum lift to drag ratio of a flat delta wing at moderate supersonic and hypersonic speeds can be increased appreciably by letting a small amount of air pass through narrow gaps located at proper places on the wing. The increase in (L/D)max obtained from such a wing experiment varies from 5% to 17% at different speeds. Six gap configurations were tested at four different free stream Mach numbers, M = 4, 4.5, 5 and 8. Reynold's number was kept constant at Re/in = 300,000 and 700,000. Both the lift and drag of the wing were reduced due to the presence of gaps. Since the decrease in drag is greater than that of lift, L/D is thus increased. The reduction in lift is due to the loss of momentum and the increase of pressure in the induced separation region on the leeward side of the wing; the reduction in drag is due to the decrease in skin-friction caused by gap effects. (Author)

Descriptors :   (*DELTA WINGS, HYPERSONIC CHARACTERISTICS), BLUNT BODIES, SUPERSONIC CHARACTERISTICS, AERODYNAMIC SLOTS, LIFT, DRAG, SKIN FRICTION, SWEPTBACK WINGS, ANGLE OF ATTACK, REYNOLDS NUMBER, BOUNDARY LAYER, FLOW SEPARATION, INJECTION, REDUCTION

Subject Categories : Aerodynamics
      Aircraft
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE