injector Definition and 20 Threads

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.
A steam injector is a typical application of the principle used to deliver cold water to a boiler against its own pressure, using its own live or exhaust steam, replacing any mechanical pump. When first developed, its operation was intriguing because it seemed paradoxical, almost like perpetual motion, but it was later explained using thermodynamics. Other types of injector may use other pressurised motive fluids such as air.
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.

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  1. S

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    I'm building a fertigation system using 1 inch venturi injector with ball valve at the end to simulate drip irrigation system pressure requirement. i have read to start an injection you need 30% pressure difference between injector inlet and outlet. the pressure I'm simulating is around 10 meter...
  2. A

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  3. Austin_Tx_Rockets

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    The discharge coefficient is the ratio of the actual discharge to the ideal discharge and can be measured experimentally. If one were to experimentally measure the discharge coefficient using water, would this value be constant for all incompressible fluids? What does the discharge coefficient...
  4. S

    Diesel Injector and Water Tube Boiler Back-Pressure

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  5. W

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  6. kunalvanjare

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  7. W

    Hybrid Rocket Injector Plate Design Research

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  8. Roy S Ramirez

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  9. Roy S Ramirez

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  10. eigenmax

    Need a small valve for gas injection? Any ideas?

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  11. P

    Some questions about Steam Injector principle

    http://www.mekanizmalar.com/how-steam-injectors-work.html In the link above, the basics of steam injector is given. Steam Injector's don't have any moving parts and doesn't consume any energy by themselves. Still, it can be able to pressurise water and inject that to a high pressure Boiler by...
  12. H

    Calculating Entrained Flow in Injector Design: Challenges and Considerations

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  13. M

    Diesel injector sac pressure calculation

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  14. P

    Non-steady suction induced by Venturi Injector

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  15. crador

    Fluid Dynamics pipeline with a venturi injector

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  16. M

    How to Measure Volume/Injection in a CRI Engine Injector Tester?

    Hello all. I have a project to make the injector tester for CRI engine. Any ideas how to measure volume / injection ? Hery
  17. P

    Automotive Fuel Injector Angle Within Fuel Injector Port

    I'm trying to find information regarding the angle of the fuel injector with respect to the air intake. Basically, I want to know how important it is, and how changing that angle would affect the performance of a vehicle. I'm working on a Formula SAE race car, and my team and I are looking to...
  18. G

    How to select the Injector for CNG application

    Help me Guys How to select the Injector for CNG application
  19. M

    The Mystery of Electronic Fuel Injectors - How Do They Work?

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  20. Clausius2

    Fuel injector surrounded by a coaxial air stream

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