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Water hammer in pipelines based on different friction models.
Dan Jiang1, Chen Zeng2, Qixia Lu2
1School of Mechanical and Electrical Engineering, University of Electronic Science and Technology of China, Chengdu, China. jdan2002@uestc.edu.cn.
Scientific Reports
|January 10, 2024
Summary
This study addresses water hammer in pipelines by comparing friction models. An impulse response function model shows better agreement with experimental results for pipeline transient analysis, improving simulation accuracy.
Area of Science:
- Fluid Dynamics
- Hydraulic Engineering
- Pipeline Systems
Background:
- Water hammer in pipelines presents significant challenges in fluid transmission.
- Discrepancies between simulation models and experimental results often arise due to pipeline transient friction models.
Purpose of the Study:
- To investigate the impact of friction models on pipeline pressure transients.
- To compare the Kagawa friction model with an impulse response function model.
- To analyze the influence of friction on cavitation and transient behaviors.
Main Methods:
- Calculated pressure transients with and without cavitation using two friction models.
- Analyzed simulation results including pressure, velocity, steady and dynamic friction, and cavitation volume.
- Examined friction features in pipelines with upstream and downstream valves.
Main Results:
- The impulse response function model demonstrated higher consistency with experimental data compared to the Kagawa model.
- The study captured distinct features of steady and dynamic friction under different valve conditions.
- The effect of friction items on pressure transients and cavitation was quantitatively revealed.
Conclusions:
- The impulse response function model offers improved accuracy for simulating pipeline transients.
- Accurate friction modeling is crucial for reliable water hammer analysis in pipelines.
- This research enhances the understanding of friction dynamics in transient fluid flow.
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