4枚羽根インデューサの交互不等翼弦長化が非定常キャビテーションに与える影響 : (第2報, 不等翼弦長比が大きい場合)

With an aim of suppressing the rotating cavitation by cutting back the leading edge alternately, 4-bladed inducers with uneven blade length were designed. Effects of the uneven blade length on unsteady cavitation were examined. It was observed that the range of the alternate blade cavitation and asymmetric cavitation were extended by increasing the amount of alternate cutting back. As the result, on 4-bladed inducer with strong uneven blade length, the rotating cavitation and cavitation surge were almost suppressed for a wide range of flow rate and cavitation number, while the suction performance was deteriorated. However, we should note that the asymmetric cavitation that occurs more easily in uneven blade inducer may cause the synchronous shaft vibration, and unevenness causes the blade stress uneven.