扩张管和燃料部分填充对PDE效能的影响

采用基于有限速率基元化学反应模型的网格自适应有限体积方法,数值模拟以脉冲爆轰发动机为背景的爆轰波通过扩张喷管的流场,研究了喷管形状及喷管充气状况对脉冲爆轰发动机推进性能的影响。结果表明,氢-氧混合物产生爆轰波的等截面爆轰管冲量在某一比例合适的部分填充时达到最大,而对较大扩张角的喷管来说,其冲量一般随喷管内可燃气体填充比例的增加而增加,比冲通常随可燃气体填充比例的减少而增加;合适的喷管和燃料填充系数能使比冲显著提高。

Influence of PDE performance on divergent channel and partial fuel filling

A grid adaptive finite volume method combined with kinetic chemical reaction model is adopted to simulate the flow field of detonation wave propagating through a divergent channel.The investigation is focused on the performance of pulse detonation engine depending on the nozzle shape and the partial fuel fill in the chamber.It is found that the impulse of the straight detonation tube with a hydrogen-oxygen mixture achieves its maximum at a certain filling factor.On the other hand,as to the nozzles with a larger divergent angle,the impulse increases with increasing fuel filling,although in most case the specific impulse increases with the decrease in fuel filling.The specific impulse is obviously improved if the nozzle shape and fuel filling are designed properly.