| 摘要 |
PROBLEM TO BE SOLVED: To allow impellers of any sizes to exhibit great resistance to the start of cavitations resulting from fluctuations in the magnitude and direction of flow velocity in space and time. SOLUTION: The impeller 22 having blades 44 formed to reduce cavitations, vibrations, noises, and physical damage to the important components of a master ship facility has a front edge 52 of each blade which skews forward over at least 70% of the outside of its span, with the forward skew being at its maximum at an end 56, which is greater than 35 deg., and preferably greater than 50 deg.. The impeller has a projected blade area ratio which is greater than 1.5, and the chord length of each blade increases gradually from a minimum skew point to the end to reduce loads in the critical area of cavitations. A partial or general end strip may be fixed to the end of the blade.
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