Foreign matter adhesion prevention structure of a centrifugal compressor impeller back

摘要

PROBLEM TO BE SOLVED: To provide surely and inexpensively a foreign material adhesion prevention structure on a rear surface of a centrifugal compressor impeller capable of preventing invasion and adhesion of foreign materials such as fine powders to the rear surface of the impeller without increasing vibration performance or centrifugal force by increasing the weight of rotor or without needing additional motive energy.;SOLUTION: In the foreign material adhesion prevention structure on the rear surface of the centrifugal compressor impeller for preventing the adhesion of foreign materials such as foreign matters by supplying buffer gas to the rear surface of the impeller of the centrifugal compressor, the impeller rear surface 1b is shaped into a smooth face, a gap of a generally constant size S is formed along the impeller rear surface 1b to at least 1/2 or more of diameter of the impeller radius R from the impeller outer periphery 1c between the impeller rear surface 1b and the facing face 3a of a stationary side casing facing the impeller rear surface 1b, thereby the average velocity of the buffer gas in the impeller rear surface 1b is increased to prevent the foreign materials such as fine powders from adhering to the impeller rear surface 1b.;COPYRIGHT: (C)2012,JPO&INPIT