Abstract: A shrouded impeller for centrifugal compressors, and methods for manufacturing shrouded impellers for centrifugal compressors are provided. In one embodiment, the method includes manufacturing an impeller base, then depositing by cold spraying at least one layer of metallic material on the surface of the frontal part of the impeller corresponding to the shroud of the impeller and machining the impeller to complete and finish the structure thereof. The at least one layer deposited by cold spraying may include grooves adapted to optimize the dynamic behavior of the impeller by modifying and tuning the local natural frequencies.

Abstract: A diaphragm 1 for a centrifugal compressor having a rear surface 2 configured to at least partly face an impeller 3, the rear surface 2 having a first portion 2a defining at least in part a diffuser 4 and a second portion 2b facing the impeller 3; the diaphragm has a duct 5 provided with an inlet 6 and an outlet 7, the outlet 7 being located on the second portion 2b of the rear surface 2, the inlet 6 being located on the rear surface 2 at a point where the static pressure is higher with respect to the static pressure at the outlet 7.

Abstract: A diaphragm 1 for a centrifugal compressor having a rear surface 2 configured to at least partly face an impeller 3, the rear surface 2 having a first portion 2a defining at least in part a diffuser 4 and a second portion 2b facing the impeller 3; the diaphragm has a duct 5 provided with an inlet 6 and an outlet 7, the outlet 7 being located on the second portion 2b of the rear surface 2, the inlet 6 being located on the rear surface 2 at a point where the static pressure is higher with respect to the static pressure at the outlet 7.

Abstract: A centrifugal turbomachine comprising a casing, a rotor assembly comprising at least one centrifugal impeller for a fluid flowing from an inlet side to an outlet side of the impeller, and an eye seal extending between an impeller eye of the centrifugal impeller and the casing for preventing the fluid from leaking between the casing and the centrifugal impeller, wherein the eye seal comprises at least a first portion toward the inlet side and a last portion toward the outlet side of the impeller, the last portion being smaller in diameter than the first portion.

Abstract: A centrifugal turbomachine comprising a casing, a rotor assembly comprising at least one centrifugal impeller for a fluid flowing from an inlet side to an outlet side of the impeller, and an eye seal extending between an impeller eye of the centrifugal impeller and the casing for preventing the fluid from leaking between the casing and the centrifugal impeller, wherein the eye seal comprises at least a first portion toward the inlet side and a last portion toward the outlet side of the impeller, the last portion being smaller in diameter than the first portion.