多级消能计算研究及优化分析  

Calculation and optimization analysis of multistage energy dissipation

作　　者：黄朝煊 HUANG Chaoxuan(Zhejiang Design Institute of Water Conservancy and Hydroelectric Power,Hangzhou 310002)

机构地区：[1]浙江省水利水电勘测设计院,杭州310002

出　　处：《水力发电学报》2018年第11期75-84,共10页Journal of Hydroelectric Engineering

基　　金：浙江省基础公益研究计划项目(LGF18E090004);浙江省水利厅科技计划项目(RC1701);浙江省水利水电勘测设计院科标业项目(B1803)

摘　　要：针对现有多级消能计算较繁琐,特别是消能计算过程中需多次反复试算查表的问题,文章基于水力学理论、数学推导及Matlab软件数值分析,对多级跌水消能、多级实用堰消能分别进行了总结分析,为多级消能优化设计提供基础。基于一元三次方程的卡当解理论给出了收缩水深、跃后水深以及水跃长等水力参数的解析计算式,并通过无量纲原理及Matlab软件分别绘制了流速系数φ=0.80、φ=0.85、φ=0.90、φ=0.95及φ=1.0时相对跃后水深h_c′/T_0、相对水跃长L_j/T_0的高精度解析计算式、简洁查算表及查算曲线图,便于工程师实际应用;同时基于消力池池深极值理论,给出了末级消力池深的直接解析计算式。最后通过两个算例进行对比计算分析,认为文中理论精度较高且方便快捷;值得说明的是,在考虑工程实际地形、地质状况及开挖费用等影响下,采用等水头落差式多级消能方案不一定最优,需采用多种不同水头落差方案进行优化比选,以节省工程投资。This paper analyzes multistage energy dissipation using the theory of hydraulics, mathematical derivation, and numerical analysis with Matlab to simplify repeated calculations in the design of multistage dissipators of water drops or practical weirs and lay a basis for optimal design of such dissipators. First, we derive analytical formulae for calculating contracted flow depth, depth after the hydraulic jump, and jump length, among other hydraulic parameters, by applying the Cartesian solution theory of cubic equations. And for the given flow coefficient φ = 0.80, 0.85, 0.90, 0.95 and 1.0, we work out high-accuracy lookup tables and curves for calculating relative flow depth hc＇/T0 and relative hydraulic jump length Lj/T0 in engineering application. Then, an analytical formula for the depth of the last stage pool is obtained using the extreme value theory of stilling pool depth. Finally, two examples are used for comparative calculation and analysis, demonstrating the accuracy and convenience of applying our formulae. This study indicates that the design scheme of a multistage dissipator adopting equal head drops may not be optimal if considering the topography, geological conditions and excavation costs of the project. Thus, a variety of head drop alternatives should be compared and optimized to save project cost.

关 键 词：工程水力学 多级消能 水深 坎高 池深 投资优化 

分 类 号：TV131.4[水利工程—水力学及河流动力学]