In part 1 of this paper the shape of an axially symmetric ducted body, of given length and fineness ratio, having minimum pressure drag was derived using the Newtonian impact pressure law. It was shown that this shape closely approximated that found by a computer method of Guderley, Armitage and Valentine which employed the general flow equations. Indeed the two curves could be distinguished only for values of the diameter ratio Δ=di/df, of the initial and final diameters, so small as to be outside the range likely to be used for cowl shapes.
Bodies Having Minimum Pressure Drag in Supersonic Flow: Investigating Nonlinear Effects