Experimental investigation on pulse detonation engine nozzles

Test results from an experimental investigation of the effect of nozzle on the thrust of a straight tube pulse detonation engine are presented. Transient thrust measured by load cell are much dependent on thrust sled dynamic characteristic: thrust peak lags behind pressure peak of thrust wall significantly and changes as operating frequency increases. Average thrust level increases non-linearly with operating frequency. On the contrast to the thrust of non-nozzle PDE, convergent nozzle with an ejector has the highest thrust augmentation, the second is convergent nozzle without ejector. Divergent nozzle can augment thrust only when operating frequency is very low, and augmentation ratio of convergent nozzle decreases as frequency increases. When located in the range of -0.3 ∼ 1 times nozzle diameter downstream of the PDE outlet, ejector has higher thrust augmentation.