EJECTOR

摘要

An ejector includes a nozzle having a fluid passage circular in cross section. The fluid passage includes a throat portion smallest in cross-sectional area, a divergent portion that becomes larger in cross-sectional area toward a downstream side from the throat portion, and an ejection port that is provided at a downstream end of the divergent portion. A passage wall surface of the divergent portion includes a recess portion that is recessed from within outward in a radial direction of the passage wall surface. The recess portion is located adjacent to the ejection port, and the recess portion extends continuously in a circumferential direction of the passage wall surface to enclose the fluid passage and have an annular shape. Accordingly, noise due to an expansion wave of the ejected fluid can be reduced.

主权项

1. An ejector comprising:
a nozzle that ejects a fluid, wherein the nozzle includes therein a fluid passage having a circular shape in cross section, the fluid passage includes:
a throat portion that is smallest in cross-sectional area and depressurizes the fluid flowing into the fluid passage;a divergent portion that becomes larger in cross-sectional area toward a downstream side from the throat portion in a flow direction of the fluid; andan ejection port that is provided at a downstream end of the divergent portion and is a port through which the fluid in the divergent portion is ejected, a passage wall surface of the divergent portion includes a recess portion that is recessed from within outward in a radial direction of the passage wall surface, the recess portion is located adjacent to the ejection port and the recess portion extends continuously in a circumferential direction of the passage wall surface to have an annular shape.