Single bubble ignition after shock wave impact

The ignition behavior of single bubbles during the first oscillation after a shock wave impact was investigated experimentally. The bubbles were created by injection of oxygen into liquid cyclohexane. High speed pressure and optical measurements were applied. The experiments were performed inside cyclohexane, at room temperature and at an initial pressure of 1 bar. It was found that an incident shock wave with a peak pressure of 85 bar ± 8.5 bar can ignite bubbles with equivalent initial diameters between 2.4 and 7.2 mm. Measurements related to the shock-induced bubble compression process, the jet formation inside the bubble, the ignition delay, the light illumination during the bubble explosion, as well as other aspects of the observed bubble behavior are presented. In addition to the experimental observations a theoretical analysis is presented. The set of equations for the theoretical estimation of the pressure and the temperature and of the gaseous mixture inside the bubble at the moment of the observed bubble ignitions is shown and explained.