| 引用本文: | 董志勇,贾代鲁,韩岩,曾团.黏性沙级配对高速水流空化空蚀的影响[J].哈尔滨工业大学学报,2023,55(2):54.DOI:10.11918/202202028 |
| DONG Zhiyong,JIA Dailu,HAN Yan,ZENG Tuan.Effect of cohesive sediment gradation on cavitation and cavitation erosion in high velocity flow[J].Journal of Harbin Institute of Technology,2023,55(2):54.DOI:10.11918/202202028 |
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| 摘要: |
| 为研究黏性沙不同级配对高速水流空化空蚀的影响及机制,利用自主研发的小型循环式水洞试验装置,采用两条不同的黏性沙级配曲线进行较系统的试验研究。通过配置黏性沙小于某一粒径不同质量分数的挟沙水流,用压力动态数据采集系统实时量测水洞工作段空化区和空蚀区的压力；制作不同配合比的混凝土试件,使混凝土试件在黏性沙小于某一粒径不同质量分数工况下进行4 h的空蚀试验,以混凝土试件每小时质量损失表征空蚀量。结果表明:水洞工作段空蚀区各测点的时均压力和空化数随黏性沙小于某一粒径质量分数的减小而增大；混凝土试件空蚀量随黏性沙小于某一粒径质量分数的减小而增加；流速相同时,较高强度配合比混凝土试件的抗空蚀能力明显优于较低强度配合比的混凝土试件；较低流速下空蚀区主要位于试件前段,较高流速下则位于试件后段；试验所用黏性沙细颗粒比重越大,空蚀量越大。 |
| 关键词: 黏性沙 级配 空化空蚀 高速水流 混凝土试件 |
| DOI：10.11918/202202028 |
| 分类号:TU398.9 |
| 文献标识码:A |
| 基金项目:国家自然科学基金(51979248) |
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| Effect of cohesive sediment gradation on cavitation and cavitation erosion in high velocity flow |
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DONG Zhiyong,JIA Dailu,HAN Yan,ZENG Tuan
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(College of Civil Engineering, Zhejiang University of Technology, Hangzhou 310023, China)
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| Abstract: |
| To study the effect and mechanism of cohesive sediment gradation on cavitation and cavitation erosion in high velocity flow, we selected two cohesive sediment gradation curves and conducted research in a self-developed small looped water tunnel. Sediment-laden flows with different mass percentages of cohesive sediment smaller than a certain grain size were prepared, and the real-time pressure within cavitation and cavitation erosion zones in working section of water tunnel was measured by a dynamic pressure data acquisition system. Concrete specimens with different mix proportions were prepared. Tests of cavitation erosion on the concrete specimens under different mass percentages of cohesive sediment smaller than a certain grain size were carried out for 4 h. The mass loss of concrete specimen per hour was adopted to characterize the cavitation erosion amount . Results show that the time-averaged pressure and cavitation number at each measurement point in the cavitation erosion zone of the working section of water tunnel gradually increased with the decrease in the mass percentage of cohesive sediment smaller than a certain grain size. With the decrease in the mass percentage of cohesive sediment smaller than a certain grain size, the cavitation erosion amount of concrete specimens gradually increased. The anti-cavitation erosion capacity of concrete specimens with higher strength was significantly greater than that with lower strength at the same flow velocity. Cavitation zone was mainly located in the front of the specimen at lower velocity, while it was located in the rear at higher velocity. Under the same sediment concentration, the higher the percentage of cohesive fine grain used in the test, the greater the cavitation erosion amount was. |
| Key words: cohesive sediment grain gradation cavitation and cavitation erosion high velocity flow concrete specimen |
