有压与无压交接水力系统有限体积法模拟分析
Finite volume method simulation analysis of combined hydraulic transients of pressurized pipe flow and open channel flow
吴金远 1周领 2胡垠盈 3许宇阳3
作者信息
- 1. 河海大学水利水电学院,江苏 南京 210098;上海市政设计研究总院(集团)有限公司,上海 200092
- 2. 河海大学水利水电学院,江苏 南京 210098;长江保护与绿色发展研究院,江苏 南京 210098
- 3. 河海大学水利水电学院,江苏 南京 210098
- 折叠
摘要
针对含无压段的长距离调水工程,采用二阶Godunov格式的有限体积法进行有压与无压交接水力计算模拟.首先根据有限体积法,分别对有压与无压的控制方程离散,采用Riemann求解器计算通量,并引入MINMOD斜率限制器进行数据重构.边界处采用虚拟边界,实现了计算区域与边界处的统一.在 1 个无压计算时步内,进行数个有压计算,从而实现有压与无压的交接计算.将所建模型与传统特征线法计算结果进行对比,验证了所建模型的精确性.结果表明,在库朗数小于 1.00 时,MOC在有压流与无压流均会产生较大的计算误差,而FVM计算更加准确.对比了有压与无压交接水力计算结果与有压段独立计算的结果,后者结果更加保守,工程经济性较差,证明了提出的有压与无压的交接水力计算的必要性与准确性.
Abstract
The finite volume method(FVM)of the second-order Godunov scheme was used to simulate the long-distance water conveyance system with pressurized and open channel sections.Firstly,the governing equations of pressurized pipe flow and open channel flow were respectively discretized ac-cording to FVM,the flux was calculated by the Riemann solver,and the MINMOD slope limiters were introduced to avoid spurious oscillations during data reconstruction.The virtual-boundary approach was presented to achieve a unified computation scheme for all the control volumes at the internal domain and boundaries.In an open channel calculation time interval,several pressure calculations were carried out to realize the joint calculation of pressurized pipe flow and open channel flow.The model proposed in this paper was compared with the traditional method of characteristics(MOC)to verify the accuracy of the proposed model,and the sensitivity of the calculation time interval was analyzed.The results show that when the Courant number is less than 1.00,MOC will produce large calculation errors in both pressurized pipe flow and open channel flow,while FVMcalculations are more accurate.The re-sults of the combined hydraulic calculation of pressurized pipe flow and open channel flow were com-pared with that of the independent calculation of the pressurized section.The latter result is more con-servative,which makes the economics of the construction design stage poor.Therefore,the joint calcu-lation of pressurized pipe flow and open channel flow proposed in this study is of high necessity.
关键词
有压管流/明渠流/有限体积法/Godunov格式/水力瞬变Key words
pressurized pipe flow/open channel flow/finite volume method/Godunov scheme/hydraulic transients引用本文复制引用
基金项目
国家自然科学基金(51839008)
国家自然科学基金(51679066)
霍英东教育基金会青年教师基金(161068)
出版年
2024
国家科技期刊平台
NSTL
万方数据