溪洛渡水库水温模拟与叠梁门分层取水效果分析

Simulation of water temperature and analysis of stratified water intake effect of stoplog gates at Xiluodu Reservoir

摘要

【目的】金沙江下游梯级水库蓄水运行后，显著影响了库区水温结构及坝下河道水温变化过程。研究库区水温时空分布特征及叠梁门分层取水对河道生态环境保护具有重要意义。【方法】以溪洛渡水库为例，基于Delft3D模型模拟了库区三维水温分布，预测了叠梁门分层取水对下泄水温的提升效果。【结果】结果表明：溪洛渡水库水温呈季节性分层，春夏季节分层显著，秋冬季节几乎不分层。电站引水口前设置叠梁门可提高下泄水温，但改善幅度有限，一层叠梁门可提高0.10~0.30℃,两层叠梁门可提高0.10~0.40℃,且改善效果随着时间的推移逐渐减弱。叠梁门的布置方式对下泄水温也有一定的影响，只在部分引水口前设叠梁门对下泄水温的整体提升效果不明显。【结论】溪洛渡水库水温结构为分层型，在水温分层较为显著时，左右岸两侧同时布置叠梁门可整体提升下泄水温。模拟和预测水库水温分层规律，有效评估叠梁门分层取水效果，可为优化溪洛渡水库生态调度实施方案提供参考依据。

Abstract

[Objective] After the reservoir operation of the downstream cascade reservoirs of the Jinsha River, the water temperature structure of the reservoir area and the water temperature variation in the downstream river channel were significantly impacted. The study of the spatiotemporal distribution characteristics of water temperature in the reservoir area and the effects of stratified water intake with stoplog gates is crucial for the protection of the river's ecological environment. [Methods] Taking Xiluodu Reservoir as an example, the Delft3D model was employed to simulate the three-dimensional water temperature distribution in the reservoir area, and the effect of stratified water intake by stoplog gates on downstream discharged water temperature increase was predicted. [Results] The result indicated that the water temperature at Xiluodu Reservoir exhibited seasonal stratification, with significant stratification in spring and summer, and almost no stratification in autumn and winter. Installing stoplog gates in front of the power station intake could increase the temperature of the downstream discharged water, but the improvement was limited. Single-layer stoplog gates could increase the temperature by 0.10 to 0.30 ℃, and double-layer stoplog gates could increase it by 0.10 to 0.40 ℃. However, the improvement gradually weakened over time. The arrangement of stoplog gates also had an impact on the downstream water temperature. Installing stoplog gates at only some of the water intakes did not significantly enhance the overall temperature of the downstream discharged water. [Conclusion] The water temperature structure of Xiluodu Reservoir is stratified. When the water temperature stratification is pronounced, the overall downstream discharged water temperature can be improved by placing stoplog gates on both the left and right banks. Simulating and predicting the water temperature stratification pattern of the reservoir and effectively assessing the influence of stratified water intake with stoplog gates can provide a reference for optimizing the implementation plan for ecological scheduling at Xiluodu Reservoir.

关键词

河道型水库 / 生态调度 / 水温模拟 / 数值模拟 / 叠梁门 / Delft3D

Key words

river-type reservoir / ecological scheduling / water temperature simulation / numerical simulation / stoplog gate / Delft3D

基金资助

中国长江三峡集团有限公司自主科研项目(NBZZ202300698)

国家自然科学基金项目(52209083)