高含沙泄洪水流的荷载特性试验研究

发布时间：2018-05-21 09:58

本文选题：高含沙泄洪水流 + 孔板消能工　；参考：《水利学报》2017年11期

【摘要】：高含沙水流特性已有较多研究,但主要针对河道中的高含沙渐变水流开展的,而对高含沙河流高坝枢纽泄洪水流荷载特性的研究较少,本文开展了孔板消能工高含沙水流的时均压力和脉动压力特性研究。试验共研究了含沙量从0至300 kg/m~3,流速从1.78 m/s至3.73 m/s,共28组不同工况。结果表明:高含沙泄洪水流的时均和脉动压力的沿程分布规律与清水相同,但幅值变化规律存在差异,相同流速条件下时均压力幅值随含沙量的增加而增加,而脉动压力幅值受含沙量和流速条件的双重影响,随含沙量的增加呈现出先增加后减小的趋势;脉动压力概率密度分布符合正态;频率分布范围受水流条件影响随流速的增加而增加,其中低频分量随含沙量的增加而增加。根据试验结果,提出了高含沙泄洪水流荷载计算的修正方法,该方法对于高含沙枢纽的工程设计有重要参考价值。
[Abstract]:There have been many studies on the characteristics of high sediment flow, but mainly on the gradual change of high sediment content in the river, but less on the characteristics of flood discharge flow in the high dam project of the high sediment bearing river. In this paper, the characteristics of time-averaged pressure and pulsating pressure of high sediment flow with hole plate energy dissipator are studied. The sediment content ranged from 0 to 300 kg / m ~ (3) and the flow rate ranged from 1.78 m / s to 3.73 m / s in 28 groups. The results show that the distribution of time-averaged and fluctuating pressure of high sediment discharge flow is the same as that of clear water, but the variation of amplitude is different, and the amplitude of time-averaged pressure increases with the increase of sediment content under the same flow velocity. The amplitude of pulsating pressure is affected by both sediment concentration and flow rate, and increases first and then decreases with the increase of sediment concentration, and the probability density distribution of pulsating pressure accords with normal distribution. The frequency distribution range increases with the increase of flow velocity, and the low frequency component increases with the increase of sediment content. Based on the experimental results, a modified method for calculating the flow load of flood discharge with high sediment content is put forward, which has important reference value for the engineering design of high sediment bearing project.
【作者单位】：天津大学水利工程仿真与安全国家重点实验室;
【基金】：国家重点研发计划(2016YFC0401904) 国家自然科学基金项目(51579172,51409187,51509180) 天津市应用基础与前沿技术研究计划(青年项目)(15JCQNJC07100) 国家自然基金委创新团队(51621092)
【分类号】：TV143

【相似文献】