Measuring Methods and Effective Parameters on the Ignition Delay in Liquid Propellants

One of the effective factors in choosing a combination of rocket propulsion is ignition delay. In propulsion applications, optimizing the ignition delay time is very important. In liquid rocket, spontaneous combustion or hypergolic ignition is a very useful property to makes sure that the engine is turned on. Excessive delay leads the accumulation of non-reacted propellant in the combustion chamber before ignition and caused combustion instability which results in mechanical stresses imposed on the body and rocket hardware. On the other hand, the short ignition delay can damage the injector. In this paper, after definition of the ignition delay, its range and relation with hypergolic propellants, the importance of ignition delay and its measuring methods is investigated and the parameters affecting the ignition delay is presented.