The ejector based engine is, as an example in an ejector ramjet engine, a
propulsion duct having normal augmented ramjet elements of an inlet,
mixer, diffuser, combustor and exit nozzle that allow operating velocities
from zero to hypersonic. At the upstream end of the mixer an injector
assembly is mounted in the fluid flow path to form an ejector. The
injector assembly has one or more injector rings which have alternatively
offset injector exhaust nozzles or slots to direct fluid toward the engine
internal wall or the engine longitudinal axis respectively to improve
fluid mixing for use of a shorter mixer section. The supply of fluid to
the injector exhaust nozzles may be by fuel flow pumps and other elements
connected to injector chambers in the injector ring or by an injector
combustor external to the mixer.
