To lower noise by preventing the backflow of a boundary layer flow in a portion near both side plates of a diffuser to an impeller in a centrifugal fluid machine comprising a diffuser with a blade, particularly a low solidity cascade diffuser LSD.
The centrifugal fluid machine includes a rotatably driven impeller 1, a diffuser 4 provided at the circumference thereof and a casing 2 accommodating these components. The diffuser 4 includes a plurality of blades 18, 18, etc. formed circumferentially at equal intervals between a pair of annular side plates 17, 17. Cutouts 21, 21 are formed at both ends in the blade width direction at the front edge 19 of each blade 18 of the diffuser 4. As a result, the boundary layer flow generated on the surface of each side plate 17 is not concentrated at the front edge of the adjoining blades 18, 18 but passes through each cutout 21 to be activated due to the lowering of pressure from an outer circumferential side pressure surface 22 to an inner circumferential side negative pressure surface 23, and flows in the circumferential direction, resulting in the prevention of the backflow to the impeller 3 to suppress noise.
ODA MAKOTO
SHIBA MAKOTO
| JPS6312699U | 1988-01-27 | |||
| JPH05106597A | 1993-04-27 | |||
| JPH06281274A | 1994-10-07 | |||
| JPS53119411A | 1978-10-18 | |||
| JP2001012388A | 2001-01-16 |
Koyama
Masayuki Mukai
Takayuki Mayuki
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