Compound ejector

Abstract

The invention provides a compound ejector and relates to a fluid mixing element for fluids. A central ejector of the compound ejector is coaxially arranged in an annular ejector; outlets of the central ejector and the annular ejector are communicated with a main mixing chamber and a main mixing tube; a first main fluid is ejected from the top of the central ejector to an inlet of a central mixing tube through a central nozzle, is utilized to inject a secondary fluid entering into a central mixing chamber from a surrounding inlet at the top of the central ejector into a central mixing tube and is mixed with the secondary fluid; a second main fluid is ejected from a side position at the top of the annular ejector to an inlet of an annular mixing tube through an annular nozzle, is utilized to inject the secondary fluid entering into an annular mixing chamber from an inlet on the side position on the upper part of the annular ejector into the annular mixing tube and is mixed with the secondary fluid; and an ejected fluid at the outlet of the central mixing tube in the main mixing chamber is utilized to inject the ejected fluid at the outlet of the annular mixing tube into the main mixing tube and is mixed for the third time, thereby finishing the mixed fluid conveying in a way that the high-pressure main fluid pumps the low-pressure secondary fluid. The compound ejector is short in axial size and high in pumping and ejecting efficiency.

Description

technical field [0001] The invention relates to a flow mixing element for fluids with different pressures, in particular to a compound injector. Background technique [0002] Ejector is also called jet pump, it is a mixed flow element that uses high pressure primary fluid to eject low pressure or no pressure secondary fluid, and outputs medium pressure mixed fluid. The most typical structure among the existing ejectors is the Venturi ejector. The body of the Venturi ejector of this single-tube ejector is a long circular tube with a diameter-expanding section at the front end, and a The nozzle is provided with a secondary fluid inlet on the side of the body. The inlet of the nozzle communicates with the inlet of the main fluid, and the outlet of the nozzle extends into the diameter-expanding section of the body, so that the diameter-expanding section of the body becomes the mixing chamber of the Venturi ejector. On the body, the small-diameter pipe part connected to the out...

AI Technical Summary

Problems solved by technology

However, the primary fluid jet is located in the center of the mixing chamber, and the secondary fluid is entrained around the primary fluid jet beam. The larger the diameter of the primary fluid jet, the lower the contact rate and entrainment efficiency between the primary fluid and the secondary fluid per unit volume, that is The injection coefficient or injection ratio becomes lower, which greatly reduces the suction function of the injection pump. In order to improve the efficiency of the injection pump, the existing solution is to divide the main fluid jet into several strands, that is, to use multi-nozzle jets, but These have not changed the initial distribution state of the main fluid in the center and the secondary fluid in the periphery

Because of the occlusion of the surrounding streams, it is still difficult for the secondary fluid to be pumped into the central area of ​​the main fluid jet for mixing, which will inevitably reduce the injection ratio and mixing efficiency

In order to make the primary fluid and the secondary fluid sucked in by the outer periphery can be mixed with each other and fully transfer heat, mass transfer, and pressure equalization, for the single-tube priming that mainly relies on the turbulent diffusion of the jet in the long stroke of the mixing tube for mixing If the injector is used, it is necessary to increase the length of the mixing tube (or mixing diffuser), which results in low injection efficiency and excessive axial dimension of the injection pump.

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