水利水电技术（中英文）2025，Vol.56Issue(10)：179-190,12.DOI:10.13928/j.cnki.wrahe.2025.10.014
改进的Preissmann狭缝法在明满流负压模拟中的研究
Research on improved Preissmann slot method for negative pressure simulation of free-surface-pressurized flow
摘要
Abstract
[Objective]The Preissmann slot method is widely used in numerical simulation of free-surface-pressurized flow.However,it cannot directly simulate negative pressure.Based on the analysis of existing method,the Preissmann slot method is improved to enable the simulation of free-surface-pressurized flow process involving negative pressure.[Methods]The model was used to determine the different flow patterns based on the initial state of water head and aeration conditions.If the initial water head was lower than the top of the pipeline and the pipeline was not connected to the atmosphere,the flow was determined as negative pressure flow.For negative pressure flow,the flow cross-sectional area was treated as a frozen full-pipe flow.The Preissmann slot method was still used to solve the equation,but the water level in the equation was converted to water head.Subsequently,the calculation method for open channel flow,pressurized flow,and negative pressure flow were described,along with the unified controlling equations.The Preissmann four-point implicit scheme was used for discrete solution,so as to establish an improved one-dimensional free-surface-pressurized flow model.[Results]Multiple classic cases and numerical simulations of the tailwater transition section of a multi-stage cascade hydropower station were used for comparison and validation.The result showed that the improved Preissmann slot method could effectively simulate the transition processes of open channel flow,pressurized flow,negative pressure flow,and free-surface-pressurized flow,with no significant impact on calculation efficiency.For a specific real-world case,the calculation time was only 0.243 s longer.[Conclusion]The research indicates that in the traditional Preissmann slot method,the water head and water level remain consistent.However,for negative pressure flow,the water head and water level should be separated.In the improved Preissmann slot method,the flow cross-sectional area is treated as a frozen full-pipe flow for negative pressure conditions,and the equation solving remains consistent with the traditional method.The only modification required is converting the water level in the equation to water head,thus enabling the simulation of negative pressure flow.关键词
水力学/明满流/负压模拟/数值模拟/改进Preissmann狭缝法Key words
hydraulics/free-surface-pressurized flow/negative pressure simulation/numerical simulation/improved Preissmann slot method分类
水利科学引用本文复制引用
丁升,任炜辰,张宏伟,王志刚,任盼红..改进的Preissmann狭缝法在明满流负压模拟中的研究[J].水利水电技术（中英文）,2025,56(10):179-190,12.基金项目
国家自然科学基金项目(52209105) （52209105）
中国水科院基本科研业务费项目(HY110145B0012024) （HY110145B0012024）
流域水循环模拟与调控国家重点实验室自主研究课题(SKL2022ZD03) （SKL2022ZD03）
