基于侧向膨胀影响爆震波的自持机理

Self-sustaining mechanism of detonation wave influenced by lateral expansion

为了研究受侧向膨胀影响时爆震波的传播特性及自持机理,在实验段对比分析了当量比(0.70～2.25)和波前预混气高度(1,2,3cm)对爆震波自持传播能力的影响.实验表明:波前预混气高度越高、预混气活性越强,则爆震波抵御侧向膨胀影响的能力越强,速度亏损越小,自持传播能力越强.运用Fay流体扩张理论,Dabora和Murray速度亏损理论,并结合Zeldovich-von Neumann-Dring(ZND)模型对受侧向膨胀影响的爆震波激波角、界面角和速度亏损进行理论预测,证明Dabora的理论预测与实验值吻合很好,且发现若要受侧向膨胀影响的爆震波自持传播,则其速度亏损的极限为7.0%～11.0%.

In order to study propagating characteristics and self-sustaining mechanism of detonation wave influenced by lateral expansion,the influences of different equivalent ratios（0.70-2.25）and different premixed gas heights（1,2,3cm）on the self-sustaining propagation of detonation wave were researched in the test section.It was found that if the premixed gas height is higher and premixed gas activity is stronger,the ability of detonation wave resisting the influence of lateral expansion is stronger and velocity deficits is smaller.Based on Fay＇s fluid expansion theory,Dabora and Murray＇s velocity deficits theory and Zeldovich-von Neamann-Dring（ZND）model,the shock wave angle,interface angle and velocity deficits of detonation wave by lateral expansion can be predicted theoretically,proving that experiment is in good agreement with theoretical prediction with Dabora＇s theory.In order to keep self-sustaining propagation of detonation wave influenced by lateral expansion,the velocity deficit limitation of detonation wave is 7.0%-11.0%.