糙率对河流过饱和总溶解气体释放规律影响研究  

Study on the effect of roughness on the release of total dissolved gas from supersaturated rivers

作　　者：赵润泽 冯镜洁[1] 李然[1] 成晓龙 王浩百 Zhao Runze;Feng Jingjie;Li Ran;Cheng Xiaolong;Wang Haobai(State Key Laboratory of Hydraulics and Mountain Rivers Engineering,Sichuan University,Chengdu610065,China)

机构地区：[1]四川大学山区河流保护与治理国家重点试验室,四川省成都市610065

出　　处：《吉林水利》2025年第4期6-11,共6页Jilin Water Resources

基　　金：国家自然科学基金项目(52279073,52322905);四川省自然科学基金项目(2023NSFSC0951)。

摘　　要：高坝泄水过程中,坝下河道常伴随出现总溶解气体(TDG)过饱和现象,且在河流输运过程中释放缓慢,可能导致鱼类患气泡病,引发水生态安全问题。原型观测结果表明,过饱和TDG释放速度与河流水深、流速、紊动等水力学要素相关,天然条件下复杂环境因素影响难以分离,水力学参数对河流过饱和TDG的释放影响难以量化。本研究突破了试验室大流量过饱和TDG水流制备难题,采用长距离试验水槽,对不同粒径砂石、砾石、卵石、混凝土河床条件下过饱和TDG输运和释放影响进行研究。结果表明,在浅水条件下,水深对过饱和TDG释放影响较小,流速与水体紊动会增加单位时间内过饱和TDG释放量。不同底质引起水力学条件变化,导致TDG释放快慢不同,本研究量化了底质对过饱和TDG释放系数的影响,随着水槽底质糙率的增大,过饱和TDG的释放量增加,释放系数增大,并进一步提出了过饱和TDG释放系数和糙率的定量关系。研究成果可为真实河流过饱和TDG释放过程分区模拟和TDG时空分布规律探寻提供科学数据和技术支撑。In the discharge process of high dam,Total Dissolved Gas(TDG)is often dissolved and supersatu-rated,and it is slowly released during river transport,which may lead to bubble disease of fish and lead to wa-ter ecological security problems.The results of prototype observation show that the release rate of supersaturat-ed TDG is related to the water depth,velocity,turbulence and other hydraulic factors,and it is difficult to re-move the influence of complex environmental factors under natural conditions.In this study,the influence of supersaturated TDG transport and release under the condition of sand,gravel,pebble and concrete bed with different particle sizes was studied by using long-distance test flume in order to break through the difficult problem of preparation of large-scale supersaturated TDG flow in laboratory.The results show that the water depth has little effect on the release of supersaturated TDG in shallow water,and the increase of flow rate will increase the release of supersaturated TDG in unit time.Different sediment causes changes in hydraulic condi-tions,resulting in different TDG release speed.In this study,the effect of sediment on the release coefficient of supersaturated TDG was quantified by the roughness ratio.With the increase of the roughness ratio of flume sediment,the release coefficient of supersaturated TDG increased.Further,the quantitative relationship between the release coefficient of supersaturated TDG and the rough rate is proposed.The research results provide sci-entific data and technical support for the zonal simulation of the release process of supersaturated TDG in real rivers and the exploration of the spatial and temporal distribution of TDG.

关 键 词：过饱和总溶解气体 释放系数 糙率 水槽试验 河道 

分 类 号：P342.2[天文地球—水文科学]