EFFECT OF BODY SHAPE ON THE AERODYNAMICS OF PROJECTILES AT SUPERSONIC SPEEDS

An investigation has been made to predict the effects of forebody and afterbodyshapes on the aerodynamic characteristics of several projectile bodies atsupersonic speeds using analytical methods combined with semi-empirical designcurves. The considered projectile bodies had a length-to-diameter ratio of 6.67 andincluded three variations of forebody shape and three variations of afterbodyshape. The results, which are verified by comparison with available experimentaldata, indicated that the lowest drag was achieved with a cone-cylinder at theconsidered Mach number range. It is also shown that the drag can be reduced byboattailing the afterbody. The centre-of-pressure assumed a slightly rearwardlocation for the ogive-cylinder configuration when compared to the configurationwith boattailed afterbody where it was the most forward. With the exception ofthe boattailed afterbody, all the bodies indicated inherent static stability aboveMach number 2 for a centre-of-gravity location at about 40% from the body nose.