The Study And The Structural Design Of A Novel Adjustable Ejector

Ejector is an instrument which can improve low quality steam at cost of no mechanical work and electronic energy, it has no motive part and is applied broadly in power station, petrochemical, metallurgy, light industry, textile industry, heating engineering and refrigeration etc.Firstly, the history of ejector's development was introduced, and the formula of ejectors working performance was given and the calculated result was analyzed. Then, on the basis of the former result, a novel ejector was set up that could adjust the area of the motive nozzle. Such adjustable ejector has an spindle, which extends into the motive nozzle to change the area of the throat and is actuated either manually or by an electric positioner. The calculation model of such adjustable ejector is established to analyse the influence on the entrainment ratio, vapor pressure and vapor flux under various area of the motive nozzle throat. It is concluded that the parameter of output could be controlled in a relatively stable range by adjusting the area of the throat, so that it can reduce the dependence on that of input. At the same time, the information of structural design and the foreground of ejector's development is presented.