摘要
衡量掺气效果的传统方法主要以掺气浓度为指标,认为掺气浓度大于2%时很少发生空蚀破坏。但新的研究表明,掺气浓度即使在很低的范围也可能不发生空蚀破坏。从气泡尺寸和气核数目对初生空化的影响入手,通过分析已有数据,探索衡量掺气效果的因素,得出初步结论。掺气减蚀效果不仅与掺气浓度有关,而且还与气泡尺寸有关,低于10-3m级尺寸的气泡对空泡溃灭冲击波的削弱作用不可忽略;其他条件一定时,气核数目增大,会促进空化现象的发生。
The effect of aeration was evaluated by air concentration traditionally.Cavitation damage rarely occurs when air concentration is greater than 2%.However,according to the recent research,cavitation erosion may not occur even under low air concentration.The effect of bubble sizes and gas nuclei number on incipient cavitation was studied in this paper.The factors that measure the air entrainment effect were explored through the analysis of existing data.A conclusion is drawn that aeration eclipse effect is not only related to the air concentration,but also to the bubble size,and weakening effect of bubbles whose size smaller than 10-3 meters on shock waves of bubble collapse could not be ignored.Under the same case,cavitation phenomenon would be promoted when gas nuclei number increased.
出处
《人民黄河》
CAS
北大核心
2013年第7期125-127,130,共4页
Yellow River
基金
国家自然科学基金资助项目(50978173,51109150)
关键词
气泡尺寸
气核数目
空化
掺气
bubble sizes
gas nuclei number
cavitation
aeration
