Air Ejector An air ejector is a device which uses the motion of moving fluid to transport another fluid. It is has a wide range of application in steam ejector in boiler condenser, fresh water generator and in priming the centrifugal pump. It works on the principle of convergent /divergent nozzle as it provides the venturi effect at the point of diffusion as the tube gets narrows at the throat the velocity of the fluid increases and because of the venturi affect it pressure decreases, vacuum will occur in the diffuser throat where the suction line will be provided.
An air ejector which uses the high pressure motive fluid such as air or steam to flow through the convergent nozzle the function of the convergent nozzle is to convert the pressure energy of the motive fluid into the velocity energy. .As the pressure energy before entering the convergent nozzle is greater and the velocity is less for the fluid. At the point of discharge the pressure energy is converted into the velocity so the velocity will be greater and the pressure will be less during the discharge.