نوع مقاله : مقاله پژوهشی
نویسندگان
1 دانشجوی دکتر گروه مهندسی آبیاری وآبادانی، دانشکده کشاورزی، دانشکدگان کشاورزی و منابع طبیعی، دانشگاه تهران، کرج، ایران
2 استاد، گروه مهندسی آبیاری وآبادانی، دانشکده کشاورزی، دانشکدگان کشاورزی و منابع طبیعی، دانشگاه تهران، کرج، ایران
3 دانشیار، گروه علوم و مهندسی آب، دانشکده کشاورزی و منابع طبیعی، دانشگاه بین‌المللی امام خمینی (ره)، قزوین، ایران
چکیده
کلیدواژه‌ها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Automatic flow control valves are one of the most important parts of the conveyance, distribution, and volumetric water delivery. Automatic flow control valves are usually designed for common heads in pressurized distribution networks. In this study, a new structure has been designed for farm use to control the flow which is applied in low operation heads. A numerical simulation by Ansys Fluent was carried out after a performance examination in the laboratory. This numerical modeling will lay the groundwork for the low-cost development of the automatic flow control valve for operating in a wide range of heads and flow rates. Due to the mobility of the internal components of this control valve, its dynamic simulations are complex and require the use of a dynamic mesh, which is very time-consuming to implement. In this research, to reduce the time of dynamic simulation, conventional assumption is considered to simplify the flow field geometry and its results are reported based on the results. The results show that excluding a guide rod from geometry, whilst facilitate dynamic simulation and decrease simulation time, also leads to a one-sided systematic error ranging from 2.7 to 4.9 percent. Since the direction of the discharge estimation error is one-sided, the correlation relationship of the results was presented and reported in this study.
کلیدواژه‌ها [English]
EXTENDED ABSTRACT
The simultaneous challenges of increasing water scarcity and the rising demand for agricultural products have highlighted the need for optimizing water usage. Volumetric water delivery has emerged as a method to enhance the efficiency of water distribution. To ensure consistent discharge and uniform distribution, the implementation of an automatic flow control valve in water networks is vital. These valves are designed to be unaffected by fluctuations in upstream and downstream water levels. This study evaluates the performance of an automatic flow control valve in regulating flow within a specific range of differential pressure, using experimental data. By utilizing supercomputers and numerical models, we employed computational fluid dynamics (CFD) simulations, particularly using Ansys Fluent software, to analyze the flow control valve. These simulations are aimed at solving complex hydraulic and mechanical issues. To reduce simulation time and computational expenses during dynamic runs, certain assumptions, including geometry simplifications, were made. The final outcomes of this numerical analysis are also discussed.
The valve was designed specifically for low head, i.e., agricultural applications, with a size chosen to handle a discharge rate of 3 L/s. Additionally, it can be installed in group to increase discharge capacity. A key advantage of this valve is its suitability for low discharge and low head conditions. The modular range of the automatic flow control valve extends from 35 to 165 cm. Unique experimental data were compiled to verify the numerical model results. The numerical simulation was carried out using Ansys Fluent under two distinct conditions: in the first the full geometry details was used, which resulted in high computational execution time. In the second condition a simplified geometry was used that significantly reduced the run time while introducing a marginal systematic simulation deviation with that of the first results. A correction equation, derived from the CFD results, was proposed to estimate and correct the deviations caused by removing the guide rod from the geometry in the second.
Ansys Fluent was employed to simulate fluid flow through a discharge control valve. The numerical simulation led to the development of this valve to be applicable across a wide range of differential pressures and various discharge rates. Static validation was performed using experimental data, and the dynamic simulation was based on the mentioned validation. The error percentage in flow rate estimation was calculated. The simulation was also conducted after simplifying the geometry, and the error percentage was determined similarly. The two sets of results were compared with experimental data. The findings revealed that the removal of the guide rod generated small deviation form that of the full geometry simulation. However, a significant reduction in run time and ease of modeling was reached. Overall, Ansys Fluent proved to be a robust model for simulating the flow control valve with an acceptable margin of error.
Conceptualization and methodology, Bijankhan M. and Kouchakzadeh .S.; software and validation, Chavoshi M.; formal analysis, all authors; investigation and data collection, Chavoshi. M. and Kouchakzadeh S.; resources, Kouchakzadeh S.; writing—original draft preparation, Chavoshi. M.; writing—review and editing, Kouchakzadeh. S. and Bijankhan M.; supervision, Kouchakzadeh. S. and Bijankhan. M.; project administration, Kouchakzadeh. S.; funding acquisition, Kouchakzadeh. S. All authors have read and agreed to the published version of the manuscript.”
“Not applicable”
The first author would like to express her gratitude to Reza Amini for his assistance in troubleshooting software issues and offering fresh perspectives in using ANSYS. Also, she would like to thank Mr. A. Ghorbani the Lab technician for his assistance in constructing the experimental setup.
The authors avoided data fabrication, falsification, plagiarism, and misconduct.
The author declares no conflict of interest.
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