Published online by Cambridge University Press: 04 July 2016
An experimental investigation on the interference effect of lee-side balance housing bodies on the longitudinal aerodynamic characteristics of thin slab delta wings has been made using a special and novel thin three-component balance. This study has been conducted using wings with a t/c of 0.053 and sweep of 76°, 70° and 65° for three different lee-side bodies viz:Body (A), Body (B) and Body (C) of which Body (C) is the smallest. The testing was carried out at Mach number of 8·2, Reynolds number of 2·13 ˘ 106 and incidence of –4° to 12°. For the smallest body (Body (C)) tested, at the incidence at which this body first goes into the aerodynamic shadow of the wing (α = 6·5°), the difference in CN, CA, CM and L/D between the wing-body and the plain wing is around by 22%, 12%, 75% and 35% respectively. This difference decreases with increase in incidence and at the highest angle-of-attack up to which testing was done (α = 12°), the. corresponding values of CN, CA, CM and L/D are around 9%, 12%, 15% and 4% respectively. Contrary to the assumption in the literature pertinent to force measurements on thin slab delta wings, the interference of the lee-side bodies are found to be appreciable even after they come into the aerodynamic shadow of the wing.