PREDICTIONS OF LOW-ASPECT-RATIO MISSILE AERODYNAMICS

The ability of a finite volume Euler code, ZEUS, to predict low aspect ratio missile aerodynamics accurately is evaluated, By using grid clustering near the body, the results from ZEUS compare well with wind-tunnel data for Mach numbers between 3 and 4.5 and angles of attack up to 20 deg, The interference factor, Kw(o)t represents the ratio of the fin normal force in the presence of the body to the fin-alone normal force, Euler K-W(B) calculations are within 12% of wind-tunnel data over the entire angle-of-attack range, The interference factor, K-B(W), is the ratio of the incremental body force due to the presence of the fins to the fin-alone normal force. The Euler predictions of the ratio K-B(W)/K-W(B) are generally within 15% of experimental data, The final parameter examined is K-phi, which is the ratio of the incremental fin normal force in the presence of the body due to sideslip to the fin-alone normal force, Currently no wind-tunnel data have been found for comparison. Euler K-phi predictions differ considerably from slender body theory predictions due to vorticity and shock waves; however, they compare well with previous Euler solutions, This research shows that ZEUS can be used to extend the preliminary design database reliably to low aspect ratio missiles.