Experimental investigation on detonation initiation by flame jet

In order to achieve a rapid initiation of detonation in a short distance, a flame jet ignition system was applied to the pulse detonation rocket engine (PDRE). Kerosene used as fuel, oxygen as oxidizer and nitrogen as purge gas, the experiment on detonation initiation by a flame jet was successfully conducted on the multi-cycle PDRE. The flame jet was yielded with the aid of a multi-hole orifice plate mounted behind the igniter port. The experimental investigation indicates that a fully-developed two-phase detonation can be achieved in a short distance by the method of flame jet ignition. In the current experiment, the deflagration-to-detonation transition (DDT) distance obtained was approximately four times of the inner diameter of detonation tube. Compared with the approach of installing Shchelkin spiral in the detonation tube as DDT enhancement device, adopting flame jet ignition on the same PDRE model shortened the DDT distance by 60%.