بررسی آزمایشگاهی اثر محل قرارگیری مانع متخلخل پیوسته سه بعدی در کف پله سرریز پلکانی بر مشخصات جریان عبوری

فصلنامه علمی مهندسی منابع آب

مقاله 6، دوره 16، شماره 56، اردیبهشت 1402، صفحه 79-94   

نوع مقاله: مقاله پژوهشی

شناسه دیجیتال (DOI): 10.30495/wej.2023.28972.2338

نویسندگان

سید امین اصغری پری^{* 1}؛ آذین رزمخواه²؛ سید علی اصغری پری³؛ مجتبی کردناییج⁴

¹دانشیار گروه عمران، دانشکده فنی و مهندسی، دانشگاه صنعتی خاتم الانبیاء بهبهان، بهبهان، ایران .

²دانشجوی کارشناسی ارشد مهندسی عمران آب، سازه‌های هیدرولیکی، دانشکده فنی و مهندسی، دانشگاه صنعتی خاتم الانبیاء بهبهان، بهبهان، ایران.

³استادیار گروه عمران، دانشکده فنی و مهندسی، دانشگاه صنعتی خاتم الانبیاء بهبهان، بهبهان، ایران.

⁴مدرس گروه عمران، دانشکده فنی و مهندسی، دانشگاه صنعتی خاتم الانبیاء بهبهان، بهبهان، ایران .

تاریخ دریافت: 23 شهریور 1400،  تاریخ بازنگری: 17 آذر 1400،  تاریخ پذیرش: 23 اردیبهشت 1402 

چکیده

چکیده
مقدمه: در تحقیق حاضر به بررسی اثر محل قرارگیری و ارتفاع مانع متخلخل سه بعدی (دارای تخلخل در هر سه بعد) که به­صورت پیوسته در عرض فلوم بر روی کف پله قرار گرفته است و همچنین اثر تعداد پله­های دارای این نوع مانع متخلخل بر روی سرریز پلکانی پرداخته شده است.
روش­: شیب سرریز 1:2 و دارای 8 پله، ارتفاع کلی 87 سانتی­متر و عرض فلوم 1.2 متر بوده است. ابزارهای اندازه­گیری در تحقیق حاضر عمق سنج، تکنیک پردازش تصویر و مشاهدات زمان انجام آزمایش بوده است.
یافته ­ها: در مانع متخلخل سه بعدی پیوسته با توجه به ارتفاع نسبی، محل قرارگیری و تعداد پله­های دارای مانع، مرزهای شروع جریان قرارگیری نسبت به حالت شاهد تغییر می­کند به­طوری­که با افزایش فاصله نسبی مانع از لبه پلکان و کاهش تعداد پله­های دارای مانع متخلخل پیوسته، تمایل جریان به گسترش در محدوده بالایی جریان انتقالی (همسایگی با جریان رویه­ای) افزایش می­یابد.
نتیجه­ گیری: در رژیم جریان ریزشی قرارگیری مانع متخلخل سه بعدی برای متغیرهای تحقیق حاضر سبب افزایش استهلاک انرژی تا 5 درصد بیش­تر نسبت به حالت شاهد می­گردد. برای رژیم­های جریان انتقالی و رویه­ای در اکثر موارد قرارگیری مانع متخلخل پیوسته اثر استهلاکی مثبت ندارد. همچنین با توجه به اندازه­های ناحیه­های شکل گرفته حاصل از BIV می­توان بیان کرد که در شرایطی که ناحیه اختلاط اندازه­گیری شده در دو پله متوالی نسبت به حالت شاهد دارای مقدار بیش­تری بوده است، استهلاک انرژی نیز افزایش یافته است.

کلیدواژه‌ها

سرریز پلکانی؛ مانع متخلخل سه بعدی؛ تکنیک BIV؛ استهلاک انرژی

عنوان مقاله [English]

Experimental Study of the Effect of the Location of a Continuous Porous Obstacle on the Bottom of a Stepped Spillway on the Characteristics of the Flow

نویسندگان [English]

Seyed Amin Asghari Pari¹؛ Azin Razmkhah²؛ Seyed Ali Asghari Pari³؛ Mojtaba Kordnaeij⁴

¹Associate Professor, Department of Civil Engineering, Faculty of Engineering, Behbahan Khatam Al Anbia University of Technology, Behbahan, Iran.

²M.sc. Sudent, Department of Civil Engineering, Faculty of Engineering, Behbahan Khatam Al Anbia University of Technology, Behbahan, Iran.

³Assistant Professor, Department of Civil Engineering, Faculty of Engineering, Behbahan Khatam Al Anbia University of Technology, Behbahan, Iran.

⁴Lecturer, Department of Civil Engineering, Faculty of Engineering, Behbahan Khatam Al Anbia University of Technology, Behbahan, Iran.

چکیده [English]

Abstract
Introduction: In the present study, we investigated the effect of the location and height of a three-dimensional porous obstacle (with porosity in all three dimensions) which is located on the bottom of the steps in the width of the flume and the number of steps with this type of obstacle has been investigated on a stepped spillway.
Methods: The slope of the spillway was 1: 2 and had 8 steps, the total height was 87 cm and the width of the flume was 1.2 m. The measuring instruments in the present study were point gage, image processing technique and observations of the experiment.
Findings: In a continuous three-dimensional porous obstacle, according to the relative height, location and number of steps with an obstacle, the starting flow boundaries of the placement change compared to the flat step, so that by increasing the relative distance of the obstacle from the edge of the steps and decreasing the number of steps with continuous porous obstacle. The tendency of the flow to expand in the upper range of the transition flow (neighborhood with the skimming flow regime) increases.
Conclusion: In the nappe flow regime, the placement of a three-dimensional porous obstacle for the variables of the present study increases the energy dissipation by up to 5% more than in the flat step (control). For transitional and skimming flow regimes, in most cases, continuous porous obstacle placement has no positive depreciation effect. In addition, according to the size of the areas formed by BIV, it can be said that in conditions where the mixing area measured in two consecutive steps was more than the flat step, energy dissipation has also increased.

کلیدواژه‌ها [English]

Stepped Spillway, 3D porous Obstacle, Energy Dissipation, BIV Technique

مراجع

1.        Akhgar, S., Roushangar, K. 2020. Numerical and experimental study of pitched steps effects in stepped spillway on the hydraulic parameters and energy dissipation in the skimming flow. Amirkabir Journal of Civil Engineering, 52(8), 2043-2058. [In Persian].

2.       Amador, A., Sánchez-Juny, M., & Dolz, J. 2006. Characterization of the nonaerated flow region in a stepped spillway by PIV

3.       ANDRÉ, S. 2004. High velocity aerated flows on stepped chutes with macro-roughness elements. Ph.D. thesis, Laboratoire de Constructions Hydraulics (LCH), EPFL, Lausanne, Switzerland, 272 pages.

4.       Asghari Pari, S. A, Kordnaeij, M. 2019. Investigating the Effect of eliminate of lateral discontinuous Obstacle on the Stepped Spillway on Flow Characteristics with image processing. 18th Iranian Hydraulic Conference. Tehran, Iran. [In Persian].

5.       Asghari Pari, S. A, Kordnaeij, M. 2021. Investigating the Effect of Different Arrangements of Obstacle on the Stepped Spillway on Flow Characteristics and Energy Dissipation. Irrigation Sciences and Engineering, 43(4), 33-49.

6.       Bung, D. B., & Valero, D. 2015, June. Image processing for bubble image velocimetry in self-aerated flows. In 36th IAHR World Congress (pp. 6594-6601).

7.       Bung, D. B., & Valero, D. 2016. Optical flow estimation in aerated flows. Journal of Hydraulic Research, 54(5), 575-580.

8.       Bung, D.B. and Schlenkhoff, A. 2010. Self-aerated skimming flow on embankment stepped spillways: the effect of additional micro-roughness on energy dissipation and oxygen transfer. Proceedings of 1 st European IAHR Congress, Edinburgh, Flash-drive.

9.       Emadzadeh, A., Chiew, Y. M. 2017. Bubble Dynamics and PIV Measurements in a Hydraulic Jump. The 37thIAHR World CongressAugust 13 – 18, Kuala Lumpur, Malaysia.

10.   Felder, S and Chanson, H. 2014. Effects of Step Pool Porosity upon Flow Aeration and Energy Dissipation on Pooled Stepped Spillways. Journal of Hydraulic Engineering, ASCE, Vol.140, No. 4, Paper 04014002, 11 pages.

11.    Felder. S, Ph. Guenther, and Chanson, H 2012. Air-water flow properties and energy dissipation on stepped spillways: A physical study of several pooled stepped configurations, School of Civil Engineering. The University of Queensland, Brisbane QLD 4072, Australia. Report CH12/87.

12.   Ghaderi, A., and Abbasi, S. 2021. Experimental and Numerical Study of the Effects of Geometric Appendance Elements on Energy Dissipation over Stepped Spillway. Water, 13(7), 957.

13.   Ghaderi, A., Abbasi, S., and Di Francesco, S. 2021. Numerical Study on the Hydraulic Properties of Flow over Different Pooled Stepped Spillways. Water, 13(5), 710.

14.    Gonzalez, C. A., and Chanson, H. 2008. Turbulence and cavity recirculation in air–water skimming flows. Journal of Hydraulic Research 46.1 (2008): 65-72.

15.   Guenher, P., Felder, S., and Chanson, H. 2013. Flow Aeration, Cavity Processes and Energy Dissipation on Flat and Pooled Stepped Spillways for Embankments." Environmental Fluid Mechanics, Vol. 13, No. 5, pp. 503-525 (DOI: 10.1007/s10652-013-9277-4).

16.   Habibi, K, Asghari Pari, S. A, and Kordnaeij, M. 2021. Experimental investigating of the Effect of location of discontinuous Obstacle on the Stepped Spillway on Flow Characteristics with image processing. 19th Iranian Hydraulic Conference. Mashhad, Iran. [In Persian].

17.   KÖKPINAR, M.A. 2004. Flow over a Stepped Chute with and without Macro-Roughness Elements. Can. Jl of Civil Engineering, Vol. 31, No. 5, pp. 880-891.

18.   Kordnaeij, M, Asghari Pari, S. A. 2019. Experimental Investigating the Effect continuous Obstacle on the edge of Stepped Spillway on Flow Characteristics with image processing (BIV). 11th international River Engineering Conference, Ahwaz, Iran. [In Persian].

19.   Kordnaej, M, Asgharipari SA, Sajadi MS, and Shafaei Bajestan M. 2020. Laboratory investigation of the effect of thickness and two porous obstacles with a spacing in the Control the Turbidity Current. Water Resources Engineering, 13(44), 1-16. [In Persian].

20.   Kordnaej, M, Asgharipari SA, Sajadi MS, and Shafaei Bajestan M. 2017. Laboratory comparison of the effect of porous obstacle and porous stepped obstacle in the control of density current. J Mar Sci Technol. 2017;16(4):86–96. [In Persian].

21.   Leandro, J., Bung, D. B., and Carvalho, R. 2014. Measuring void fraction and velocity fields of a stepped spillway for skimming flow using non-intrusive methods. Experiments in Fluids, 55(5), 1732

22.   Li, S., Li, Q., and Yang, J. 2019. CFD Modelling of a Stepped Spillway with Various Step Layouts. Mathematical Problems in Engineering, 2019.

23.   Li, S., Yang, J., and Li, Q. 2020. Numerical Modelling of Air-Water Flows over a Stepped Spillway with Chamfers and Cavity Blockages. KSCE Journal of Civil Engineering, 24(1), 99-109.

24.   Lopes, P., Bung, D. B., Leandro, J., and Carvalho, R. F. 2015. The effect of cross-waves in physical stepped spillway models. In 36th IAHR world congress, The Hague.

25.   Lopes, P., Leandro, J., Carvalho, R. F., and Bung, D. B. 2017. Alternating skimming flow over a stepped spillway. Environmental Fluid Mechanics, 17(2), 303-322.

26.   Novakoski, C. K., Ferla, R., Prá, M. D., Canellas, A. V. B., Marques, M. G., and Teixeira, E. D. 2020. Stepped spillway with pre-aeration by a deflector: flow characteristics. RBRH, 25.

27.   Ostad Mirza, M. J. 2016. Experimental study on the influence of abrupt slope changes on flow characteristics over stepped spillways (No. THESIS). EPFL.

28.   Raza, A., Wan, W., and Mehmood, K. (2021). Stepped Spillway Slope Effect on Air Entrainment and Inception Point Location. Water, 13(10), 1428.https://doi.org/10.3390/w13101428.

29.   Razmkhah, A, Asghari Pari, S. A, and Kordnaeij, M. 2021. Experimental investigating of the Effect of location of continuous Obstacle on the Stepped Spillway on Flow Characteristics with image processing. 19th Iranian Hydraulic Conference. Mashhad, Iran. [In Persian].

30.   Roushangar, K., akhgar, S. 2021. Numerical and Experimental Study of Wedge Elements Influence on Hydraulic Parameters and Energy Dissipation over Stepped Spillway in Skimming Flow Regime. Amirkabir Journal of Civil Engineering, 53(1), 185-200. [In Persian].

31.   Thielicke, W., & Stamhuis, E. 2014. PIVlab–towards user-friendly, affordable and accurate digital particle image velocimetry in MATLAB. Journal of Open Research Software, 2(1).

32.   THORWARTH, J. 2008. Hydraulisches Verhalten der Treppengerinne mit eingetieften Stufen –Selbstinduzierte Abflussinstationaritäten und Energiedissipation. (Hydraulics of Pooled Stepped Spillways – Self-induced Unsteady Flow and Energy Dissipation.) Ph.D. thesis, University of Aachen, Germany (in German).

33.   THORWARTH, J. and KÖNGETER, J. (2006). "Physical Model Test on a Stepped Chute with Pooled Steps – Investigation of Flow Resistance and Flow Instabilities. In: Recent Developments on Hydraulic Structures: From Hybrid Modelling to Operation and Repairs; Cuidad Guayana, Venezuela, October 2006. International symposium on Hydraulic Structures/Ed. by Arturo MARCANO et al., Caracas, Venezuela: Venezuelan Society of Hydraulic Engineering, pp. 477 - 486 (ISBN 980-12-2177-1).

34.   Torabi, H., Parsaie, A., Yonesi, H., & Mozafari, E. 2018. Energy dissipation on rough stepped spillways. Iranian Journal of Science and Technology, Transactions of Civil Engineering, 42(3), 325-330.

35.   Zare, H. K., & Doering, J. C. 2012. Energy dissipation and flow characteristics of baffles and sills on stepped spillways. Journal of hydraulic research, 50(2), 192-199.

Zhang, G., & Chanson, H. 2018. Air-water flow properties in stepped chutes with modified step and cavity geometries. International Journal of Multiphase Flow, 99, 423-436. 55: 1732.