An Analysis of Fuel-Oxidant Mixing in Screaming Combustors

Examinat ion of Figs. 3(a) and 3(b) reveals, as is to be expected, t ha t the choice of area ratio has little effect on missile performance when the nozzle weight is a very small port ion of the burnout weight. The importance of correct choice of area ratio increases as the nozzle weight becomes more significant. Nozzle weights, in conventional practice, seldom become large enough in relation to the rest of the inert weight to invalidate the approximation made in Equa t ion [7]. The gains in velocity increment realized by correct choice of area ratio are usually only a few per cent, which m a y be impor tan t in some applications. In other cases, nozzle design m a y still be dictated by structural , cooling, etc., requirements. 2490