Invention and Engineering
An injector is a system of ducting and nozzles used to direct the flow of a high-pressure fluid in such a way that a lower pressure fluid is entrained in the jet and carried through a duct to a region of higher pressure. It is a fluid-dynamic pump with no moving parts except a valve to control inlet flow. Depending on the application, an injector can also take the form of an eductor-jet pump, a water eductor or an aspirator. An ejector operates on similar principles to create a vacuum feed connection for braking systems etc. The motive fluid may be a liquid, steam or any other gas. The entrained suction fluid may be a gas, a liquid, a slurry, or a dust-laden gas stream.
Commonwealth Railways D class.
JNR Class 9600.
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