بررسی عددی پارامترهای موثر بر هیدرولیک جریان در سرریزهای تناسبی دودکشی

نوع مقاله : مقاله پژوهشی

نویسندگان

1 استاد، گروه مهندسی عمران، دانشکده فنی و مهندسی، دانشگاه مراغه

2 دانش آموخته دکتری، گروه مهندسی آب، دانشکده کشاورزی، دانشگاه تبریز، تبریز، ایران

3 دانشجوی آب و سازه های هیدرولیکی . دانشکده فنی و مهندسی، دانشگاه مراغه

چکیده

سرریزهای تناسبی به­­دلیل تأمین دقت مورد نیاز در برآورد میزان دبی از اهمیت بالایی در اندازه­گیری جریان برخوردار هستند. در این مطالعه، با استفاده از نرم­افزار FLOW-3D پارامترهای هیدرولیکی از جمله توزیع سرعت و بردارهای سرعت، توزیع فشار سیال در کانال و سرریز، عدد فرود، نمودار دبی-اشل و ضریب­دبی سرریزهای دودکشی با زوایای (زاویه قسمت مثلثی سرریز با دیواره قائم) ˚37، ˚42، ˚2/47 و ˚53 در محدوده دبی 2 الی 9 لیتر بر ثانیه مورد بررسی قرار گرفته است. در تحقیق حاضر مدل آشفتگی RNG در مقایسه با مدل­های آشفتگی LES، k-ε و k-ω به­علت مقادیر کم درصد خطای نسبی و خطای مطلق انتخاب شد. نتایج نشان داد که با افزایش زاویه، در بار آبی یکسان، میزان دبی و عدد فرود کاهش و با افزایش بار آبی بالای تاج سرریز، عدد فرود افزایش پیدا می­کند. همچنین براساس نتایج حل عددی با کاهش زاویه، سرعت متوسط جریان در بالادست سرریز افزایش می­یابد. در این مطالعه، براساس پارامترهای بی­بعد رابطه چند جمله­ای غیرخطی با تلفیق داده­های تمامی سرریزهای مدل شده برای پیش­بینی ضریب­دبی به­دست آمد. مقایسه نتایج آزمایشگاهی و حل عددی با رابطه پیشنهادی در تحقیق حاضر، حاکی از دقت بالای معادله ارائه شده می­باشد.

کلیدواژه‌ها


عنوان مقاله [English]

Numerical Investigation on Effective Parameters on Hydraulic Flows in Chimney Proportional Weirs

نویسندگان [English]

  • Rasoul Daneshfaraz 1
  • Reza Norouzi 2
  • Hamidreza Abbaszadeh 3
1 Professor , Department of Civil Engineering, Faculty of Engineering, University of Maragheh, Iran.
2 Ph.D., Department of Water Engineering, Faculty of Agriculture, University of Tabriz, Tabriz, Iran.
3 M.Sc. Student, Department of Civil Engineering, Faculty of Engineering, University of Maragheh, Maragheh, Iran
چکیده [English]

Proportional weirs are of great importance in flow measurement due to providing the required accuracy in estimating the flow rate. In this study, the hydraulic parameters such as velocity distribution and velocity vectors, fluid pressure distribution in channel and weir, Froude number, stage-discharge diagram and discharge coefficient of chimney weirs with angles (The angle of triangular part of weir with the vertical wall) of 37˚, 42˚, 47.2˚ and 53˚ in the range of 2 to 9 liters per second was investigated using FLOW-3D software. In the present study, the RNG turbulence model was selected in comparison with the LES, k-ε and k-ω turbulence models due to low values ​​of relative error percentage and absolute error. The results showed that by increasing angle, at the same water head, the flow rate and Froude number decreases, and by increasing water head above the weir crest, the Froude number increases. Also, based on the results of numerical solution, by decreasing angle, the upstream mean velocity increases. In this study, based on dimensionless parameters, a nonlinear polynomial equation was obtained by combining the data of all modeled weirs to predict the discharge coefficient. Comparing the results of experimental and numerical solution with the presented equation indicates the high accuracy of the presented equation.

کلیدواژه‌ها [English]

  • Chimney weir
  • water head
  • Froude number
  • Velocity distribution
  • Discharge coefficient
Baddour, R.E. (2008). Head-discharge equation for sharp-crested polynomial weir: Journal of Irrigation and Drainage Engineering, 134(2), 260-262.
Carrillo, J.M., Matos, J. and Lopes, R. (2020). Numerical modeling of free and submerged labyrinth weir flow for a large sidewall angle: Environ Fluid Mech 20, 357–374
Chatterjee, C., Singh, R., Kar, S. K., Panda, S. N. and Vohra, S. L. (1998). Flow Characteristics of Chimney Weir under Submergence: Journal of Irrigation and Drainage Engineering, 124(2), 96-101.
Chatterjee, C., Singh, R. and Kar, S. K. (2002). Discharge Characteristics of Chimney Weir under Free-Flow Conditions: Journal of Irrigation and Drainage Engineering, doi: 10.1061/(ASCE)0733-9437(2002)128:3(175)
Daneshfaraz, R., Aminvash, E., Abbaszadeh, H. (2021). Numerical Simulation of Energy Dissipation in Crescent-Shaped Contraction of the Flow Path, Iranian Journal of Soil and Water Research, 52(5), 1299-1314
Daneshfaraz, R., Majedi Asl, M., Razmi, S., Norouzi, R. and Abraham, J. (2020). Experimental investigation of the effect of dual horizontal screens on the hydraulic performance of a vertical drop: Environmental Science International Journal of Environmental Science and Technology, 17(5), 2927–2936.
Elazizy, I. M., Abou EL-Atta, N. Abd El-Lateef. M. and Mohamed, Elz. F. (2004). Characterstics of Submerged Modified Chimney Weir: Ain Shams Engineering Journal, 39, 381-399
Eslahi, N., Amiri Tokaldany, E. and Vatankhah, A. R. (2014). Experimental Study on Determination of Flow Coefficient of the Linear and Quadratic Proportional Weirs in Rectangular Channels: Journal of Hydraulics, 8(4), 43-53. (In Farsi)
Ghaderi, A., Daneshfaraz, R., Abbasi, S. et al. (2020a). Numerical analysis of the hydraulic characteristics of modified labyrinth weirs. Int J Energ Water Res 4, 425–436
Ghaderi, A., Daneshfaraz, R., Dasineh, M. and Di Francesco, S. (2020b). Energy Dissipation and Hydraulics of Flow over Trapezoidal–Triangular Labyrinth Weirs: Water. 12(7), doi.org/10.3390/w12071992
Ghaffari Gousheh, J., Fatahi Nafchi, R. and Samadi Boroujeni, H. (2018). Proportional weirs performance in the lateral catchment. in: 2nd National Conference on Knowledge and Technology of Agricultural Sciences, Natural Resources and Environment of Iran, Tehran. (In Farsi)
Hayawi, H. A. M., Yahya. A. A. G.  and HayawiHanaa A .M.Hayawi Amal A.G.Yahya Ghania A.M.Hayawi  G. A. M. (2005). Coefficient of Discharge of Chimney Weir Under free and Submerged flow Conditions: Al-Rafidain Engineering Journal (AREJ), 13(1), 62-69.
Keshava Murty, K. and Giridhar, D. P. (1989). Inverted v-notch: Practical proportional weir: Journal of Irrigation and Drainage Engineering, 115(6), 1035-1050.
Keshava Murthy, K. and Giridhar, D. P. (1990). Improved Inverted V-Notch or Chimney Weir: Journal of Irrigation and Drainage Engineering, 116 (3), 374-386.
Kianmehr, A., Kouchakzadeh, S. and Vatankhah, A. R. (2015). Experimental study of linear proportional weirs for circle conduit: Iranian Water Research Journal, 8(15), 93-101. (In Farsi)
Norouzi, R., Daneshfaraz, R. and Ghaderi, A. (2019). Investigation of discharge coefficient of trapezoidal labyrinth weirs using artificial neural networks and support vector machines: Applied Water Science 9, 148, doi.org/10.1007/s13201-019-1026-5
Norouzi, R., Arvanaghi, H., Salmasi, F., Farsadizadeh, D. and Ghorbani, M. A. (2020). A new approach for oblique weir discharge coefficient prediction based on hybrid inclusive multiple model: Flow Measurement and Instrumentation, 6(11), doi.org/10.1016/j.flowmeasinst.2020.101810
Norouzi, R., Arvanaghi, H., Salmasi, F., Farsadizadeh, D. and Ghorbani, M. A. (2021). Influence of geometrical parameters on flow hydraulic properties in inclined weirs: Irrigation and Water Engineering, 11(3), 35-54. (In Farsi)
Rezazadeh, H., Manafpour, M. and Ebrahimnezhadian, H. (2020). Three-Dimensional Simulation of Flow Over Sharp-Crested Weirs Using Volume of Fluid Method: Journal of Applied Engineering Sciences, 10(1), 75-82.
Salmasi, F., Nourani, B., Norouzi, R. and Rezaei, F. (2019). Investigation the Stage-Discharge Relationship and Discharge Coefficient in Sharp-Crested Weirs with Triangular Shape in Plan: Amirkabir Journal of Civil Engineering, doi: 10.22060/ceej.2019.16931.6399. (In Farsi)
Singer, J. and Lewis, D.C.G. (1966). Proportional-flow weirs for automatic sampling or dosing: Water and Water Engineering, 70(841), 105-111.
Vatankhah, A. R. and Kouchakzadeh, S. (2009). Discussion of Head-discharge equation for sharp-crested polynomial weir, by Baddour, R.E. : Journal of Irrigation and Drainage Engineering, 135(3), 393-395.
Vatankhah, A. R. (2012). Head-discharge equation for sharp-crested weir with piecewise-linear sides: Journal of Irrigation and Drainage Engineering, 138(11), 1011-1018.