The Use of a Flash Vaporization System with Liquid Hydrocarbon Fuels in a Pulse Detonation Engine

Abstract

Abstract : In recent research, liquid fuel droplets were found to hinder the detonation process in a pulse detonation engine (PDE). In the current work, multi-phase effects are eliminated with a flash vaporization system that vaporizes the liquid fuels prior to mixing with air. Hydrocarbon and air mixtures have been transitioned from deflagration to detonations previously, but exhibited long ignition and deflagration to detonation transition (DDT) times. Here, two liquid hydrocarbon fuels, with different octane numbers (ON), are detonated with air in a PDE to determine the effect of octane number on the ignition time and the DDT time. The premixed, combustible mixture fills the PDE tubes via an automotive valve and cam system described in detail elsewhere.3 N-heptane (ON-0) and isooctane (ON-100) are evaluated individually to determine the effects of automotive octane number on pulse detonation engine combustion performance. The ON has been considered previously4 as an acceptable criterion in determining the detonability for PDEs, and it is derived based on the tendency to knock or detonate relative to isooctane in an automotive engine application.