Fuel injection strategy for a next generation pulse detonation engine

Abstract

The Pulse Detonation Engine offers the Department of Defense a new low cost, light weight, and efficient solution to supersonic flight on many of its small airborne platforms. In the past, both liquid fuel and gaseous fuel designs have been partially developed and tested. Several aspects of these configurations have led to the need for the development of a new design, in particular the reduction of total pressure losses, and the removal of auxiliary oxygen system previously required to initiate a detonation wave in fuel-air mixtures within practical distances. Furthermore, higher repetition rates are required for practical thrust levels, as well as the use of liquid fuels, as these are more attractive due to their higher energy densities. A new PDE configuration was designed to operate on the liquid fuel, JP-10. The fuel injection system was characterized using laser diagnostics so that the fuel injection strategy could be optimized for the specified operating conditions. The timing parameters for the fuel-air injection profile were characterized as well in order to deliver the desired amount and duration. This was a concurrent effort with computational simulations of the internal flow paths, design/integration of a novel transient plasma ignition system, and ongoing developments of a performance measurement test rig.