Investigation of the Spray Characteristics of the Gelled Fuel Jet A-1, using an Impinging Jet Atomizer

Abstract

Gelled fuels and propellants are of interest for rocket and ramjet propulsion systems, because of their safety and performance benefits. Due to their shear-rate dependent non-Newtonian flow behavior, they offer the possibility to build throttleable engines, which, additionally, have handling characteristics similar to the simple ones of the engines with solid fuels. The addition of gelling agents to conventional liquid fuels and the conduction of a gellation process changes their rheological properties significantly. Without any applied shear stress they are almost non-fluid with very high dynamic shear viscosity values. This state, is often described as "semi-solid". By applying high shear rates during the injection process, however, it is possible to reach relative low viscosity values and a substantial liquidification in the area near the injector exit plane.