泥沙研究

水库通常会采用定期或不定期降低水位排沙运用，形成冲刷漏斗，以保障发电洞“门前清”。为保证玉龙喀什水库取水防沙安全，研究水库排沙效果的影响因素，建立了水库坝前2.5 km范围的正态泥沙物理模型，分析了不同冲沙流量、运行水位和冲刷历时对冲刷漏斗形态的影响，结果表明：在降水冲沙条件下，水库水位降至2 080 m水位运行，关闭发电洞，2#排沙洞冲沙流量为357 m³/s, 1#排沙洞冲沙流量为319 m³/s,冲刷历时1.33 h,排沙效率最高。当控制水位排沙时，水库以2 090 m水位运行，关闭发电洞，2#排沙洞冲沙流量为357 m³/s, 1#排沙洞冲沙流量为381 m³/s,冲刷历时3.67 h,形成的冲沙漏斗最大。此外，提出了优化水工结构的“门前清”保障方案。

Reservoirs usually use regular or irregular lowering of water level for discharging sediment, forming a scouring funnel to ensure the "front clearance" of power generation tunnels. In order to ensure the safety of water intake and sediment prevention in Yulong Kashi Reservoir, to study the influencing factors of sediment discharge effect, a normal sediment physical model within a range of 2.5 km in front of the reservoir dam was established, and the effects of different flow rates for sediment flushing, dam water level and scouring duration on the shape of scouring funnel were analyzed. The results show that in the case of flushing sediment with the lowering of dam water level to 2080 m and closing the power generation tunnel, the sediment discharge efficiency reaches to its maximum when the flow rate through the No.2 and No.1 sediment flushing tunnels are 357 m³/s and 319 m³/s respectively, and the flushing duration is 1.33 h. In the case of flushing sediment with controlled dam water level, the sediment discharge funnel reaches to the largest when the dam water level of 2 090 m, the power generation tunnel is closed, and flow rates in the No.2 and No.1 sediment discharge tunnels are 357 m³/s and 381 m³/s respectively, and the flushing duration is 3.67 h. In addition, the guarantee scheme of "front clearance" is put forward to optimize the hydraulic structure.