Nozzle and steam ejector

Abstract

The invention discloses a nozzle and a steam ejector. The nozzle comprises an inlet pipe section (1), a transition pipe section (2) and an outlet pipe section (3) that are connected sequentially; a tapered expansion pipe with the inner diameter increasing along the direction from an inlet to an outlet forms at the outlet pipe section (3); a peripheral part of the outlet pipe section (3) comprises convex edge parts (31) and concave edge parts (32) that are formed in a staggered manner along the circumferential direction of the peripheral part sequentially, thus at any cross section of the outlet pipe section (3), a concave-convex petal shape is formed at an outline of an inner wall surface of the outlet pipe section (3) along the circumferential direction. With the adoption of the technical scheme, compared with a nozzle having a circular cross section, the nozzle with the cross section being petal-shaped has a greater perimeter on the condition that flow areas are equal, a contact area between the inner wall of the nozzle and a fluid is increased, the rolling suction and compounding effects of the fluid and other fluids at an outlet can be improved, an injection system can be improved, and a mixed fluid having better uniformity can be formed.

Description

technical field [0001] The invention relates to the field of fluid injection, in particular to a nozzle and a steam ejector. Background technique [0002] The steam ejector uses the supersonic low-pressure jet formed by the high-pressure steam in the Laval-type working nozzle to entrain the secondary fluid, and then forms a medium-pressure mixed steam at the outlet after being decelerated by diffusion. It is often used for vacuum preparation, fluid mixing, fluid transportation, etc. , has the characteristics of simple structure, convenient operation and maintenance. [0003] At present, the main methods to improve the performance of the steam ejector are: reasonable design of the structure and size of the ejector, mainly the area ratio of the inlet and outlet of the mixing section, the ratio of the throat area, etc. Due to the existence of shock waves in the steam injection process, a reasonable structure size can control the position and quantity of the shock waves, improv...

AI Technical Summary

Problems solved by technology

With the help of gas dynamics principle, after making appropriate macroscopic assumptions on the axial mixing principle of the two steams of the conical cylindrical injector, it is found that the mixing effect of the high-pressure steam injected by the nozzle and the ejected steam is not satisfactory

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