Thrust Measurement of a Multicycle Partially Filled Pulse Detonation Rocket Engine

In the present research, we experimentally verified the partial-fill effect in a multicycle pulse detonation rocketengine. The intermittent thrust of a pulse detonation rocket engine was measured by using a spring-dampermechanism that smoothed this intermittent thrust in the time direction. The intermittent mass flow rates wereassessed by gas cylinder pressure or mass difference measurement. The maximum specific impulse was 305 9 s atan ethylene and oxygen propellant fill fraction of 0:130 0:004. When the fill fraction was greater than 0.130, thespecific impulse was increased as the partial-fill fraction was decreased. When the fill fraction was less than 0.130, thespecific impulse was sharply decreased as the partial-fill fraction was decreased. This decrease was due to diffusionbetween propellant and purge gases and the short length of the transition from deflagration to detonation. Themulticycle pulse detonation rocket engine had a partial-fill effect that may have been mainly due to the suctioned airand was consistent with the single-cycle partial-fill model of Endo et al