Initiation of rotating detonation in experimental combustion chamber : practical realization

Since 2009 in the Institute of Aviation, Warsaw a project that aim is to develop combustion chamber with rotating detonation for turbine engine has been carried out. Desired fuel is aviation kerosene (Jet-A) detonated in air. One of the most important problems to be solved was the initiation of rotating detonation in combustible mixture, which requires the fulfilment of several conditions: 1) good mixing of combustible mixture components, 2) properly fast flow of combustible mixture in the cylinder-shaped channel, 3) the appropriate height of the flow channel, associated with detonation cell size for the combustible mixture, 4) use of a source of detonation initiation with an appropriate energy and power for a given combustible mixture. There were considered and tested, in practice several different types of initiators: a) spark electric discharge in air, b) plasma electric discharge (the so-called "exploding wire"), c) micro-explosive charges, d) blank ammunition, e) gas initiator (with detonation of acetylene-oxygen stoichiometric mixture induced by spark electric discharge). The paper summarizes the theoretical energy parameters of several types of initiators, and the results of their comparative research on the test bench. In the course of these researches, the pressures of the shock wave generated by the initiators and recorded by a fast pressure sensor located at a distance from the initiator were compared.