| 摘要 |
PROBLEM TO BE SOLVED: To generate no peeling at the pressure surface side of a guide vane even at a hub side with a small flow-out angle and to prevent the increase of the total pressure loss of a diffuser, so as to improve the efficiency. SOLUTION: In a diffuser 20, a passage space held between the side walls 10H and 10S of a casing 10 is partitioned by plural guide vanes 21 provided in the peripheral direction, at the outer peripheral side of an impeller 30, the downstream from a throat forms an expansion passage at a specific expanding angle between the guide vane 21 and an adjacent guide vane, and the guide vane 21 is incliningly formed at a specific angle, in the direction to make an angleθmade by its pressure surface and the inner surface 20H of a hub side side wall 10H, narrower than 90 deg..
|
