Influence of geometrical parameters on flow hydraulic properties in inclined weirs

Authors

1 University of Tabriz

2 University of Tabriz,, Water engineering department, 29 Bahman boulevard,

10.22125/iwe.2021.128112

Abstract

Weirs are one of the most important hydraulic structures for flow control, water measurement, and regulating of upstream water elevation in canals, irrigation networks, and rivers. For a given channel width, inclined weirs have a longer effective length in comparison with the usual rectangular sharp-crested weirs, and this could be effective on their discharge coefficients and efficiency. In the present study, the effect of the geometrical parameters on the hydraulic properties of the flow in inclined weirs was investigated using 3D Ansys Fluent software. Numerical simulations were validated by laboratory results. Weir height (P), weir angle with channel wall (α), water height above the weir (H), and effective length (Le) were investigated. The MR-linear regression model performance in applying the inclined weir discharge coefficient was investigated. The results indicated that this relation is very similar to the numerical model results. The numerical model results were also compared with those of the other researchers. Inclined weirs discharge coefficient at different effective lengths decreases by increasing H/P, and at a constant H/P, by increasing the weir effective length, the discharge coefficient decreases, and the flow rate increases. Increasing in weir height results increasing in discharge.

Keywords


بابایی، ا.، ح. کرمی و س. فرزین. 1398. بررسی عددی خصوصیات جریان در سرریز لبه تیز با مقطع افقی مثلثی با زاویه رأس در پایین­دست. فصلنامه علمی پژوهشی مهندسی آبیاری و آب ایران، سال نهم، شماره 35، ص 65-49.
نیک­پیک، پ. و م. کاشفی­پور. 1395. تأثیر شرایط هیدرولیکی و هندسه سرریز در مدلسازی ریاضی ضریب دبی سرریزهای نوک­اردکی و مایل. علوم و مهندسی آبیاری، جلد 39، شماره 1، ص 10-1.
فرزین، س.، ح. کرمی،  ف. یحیوی و ش. نیر. 1397. بررسی عددی مشخصات هیدرولیکی جریان اطراف سرریز لبه تیز قائم و مورب با شبیه سازی در نرم افزار Flow3D. مجله پژوهش های عمران و محیط زیست، دوره 4، شماره 1، ص24-15.
نورانی، ب.، ر. نوروزی، ف. سلماسی و ف. رضایی. 1398. بررسی رابطه دبی- اشل و ضریب دبی جریان در سرریزهای لبه تیز پلان مثلثی. نشریه مهندسی عمران امیر کبیر، (DOI): 10.22060/CEEJ.2019.16931.6399
 
Afzalimehr, H. and S. Bagheri. 2009. Discharge coefficient of sharp-crested weirs using potential flow. Journal of Hydraulic Research, 47(6): 820-823.
Arvanaghi, H. and G. Mahtabi. 2014. Numerical Investigation of Discharge Coefficient in Combined Weir-Gate with Equal Contraction. Journal of Current Research in Science, 2(4): 460.
Bilhan, O., M. Aydin, M. Emiroglu and C. Miller. 2018. Experimental and CFD Analysis of Circular Labyrinth Weirs. Journal of Irrigation and Drainage Engineering, 144(6), 04018001-04018007.
Crookston, B.M. and B.P. Tullis. 2012. Discharge efficiency of reservoir application specific labyrinth weirs. Irrig. Drain. Engr. ASCE. 138(6): 773-776.
Carrillo, J., J. Matos and R. Lopes. 2019. Numerical modeling of free and submerged labyrinth weir flow for a large sidewall angle. Journal of  Environmental Fluid Mechanics, 20: 357-374.
Daneshfaraz, R., O. Minaei, J. Abraham, S. Dadashi and A. Ghaderi. 2019. 3-D Numerical simulation of water flow over a broad-crested weir with openings. ISH Journal of Hydraulic Engineering,1:1-9.
Dabling, M.R. and B.P. Tullis. 2017. Modifying the downstream hydrograph with staged labyrinth weirs. Journal of Applied Water Engineering and Research, 6(3): 183-190.
Emami, S., H. Arvanaghi and J. Parsa. 2018. Numerical Investigation of Geometric Parameters Effect of the Labyrinth Weir on the Discharge Coefficient. Journal of  Rehabilitation in Civil Engineering, 6(1): 1-9.
Hay, N. and G. Taylor. 1970. Performance and design of labyrinth weirs. Hydraulic. Eng., ASCE, 96(11): 2337-2357.
Mahtabi, G. and H. Arvanaghi. 2018. Experimental and numerical analysis of flow over a rectangular full-width sharp-crested weir. Journal of  Water Science and Engineering, 11(1): 75-80.
Kumar, S., Z. Ahmad, T. Mansoor and S.K. Himanshu. 2011. A New Approach to Analyze the Flow over Sharp Crested Curved Plan form Weir. International Journal of Recent Technology and Engineering 2(1), 2277-2290.
Norouzi, R., H. Arvanaghi, F. Salmasi, D. Farsadizadeh and M.A. Ghorbani. 2020. A new approach for oblique weir discharge coefficient prediction based on hybrid inclusive multiple mode. Flow Measurement and Instrumentation. 76(11).
Taylor, G..1968. The Performance of Labyrinth Weirs. University of Nottingham, UK.
Rezaee, M., A. Emadi and Q. Aqajani Mazandarani. 2016. Laboratory study overflow rectangular Congress. Journal of Water and Soil Science, 29(6): 1438-1446.