Title Experimental Investigation of Discharge and Flow Energy Dissipation of Elliptical Lopac Gate in Free Flow Condition

Document Type : Research Paper

Authors

1 Graduate student, of Hydraulic Structure, Faculty of Water and Environmental Engineering, Shahid Chamran University of Ahvaz, Ahvaz,Iran.

2 Assistant Professor, Faculty of Water and Environmental Engineering, Shahid Chamran University of Ahvaz, Ahvaz,Iran.

3 Professor, Faculty of Water and Environmental Engineering, Shahid Chamran University of Ahvaz, Ahvaz,Iran

Abstract

Management of irrigation networks has always been one of the most important issues in the agricultural sector, and the use of modern valves and structures for controlling and adjusting the water flow is very important in irrigation channels. Water level control structures are used in irrigation canals to imple-ment delivery methods (Naghaei and Monem 2013).
Gates are one of the most used water structures in distribution canals that are used to transport and deliver water to consumer or to control the flow rate or water level. Determining the relationship governor on these structures can improve the performance of open canals and therefore prevent water loss. Lopac gate as a water level adjustment structure has recently attracted attentions and its performance in applied and practical areas of irrigation channels in different countries is accepted. The gate can be opened along the flow direction and can regulate upstream water level for various dis-charges by adjusting the gate opening angle (Oad and Kinzli 2006). So far little studies have been done on these types of gates. Some studies have examined hydraulic conditions of the flow passing through rectangular Lopac gate and presented the discharge equation as well as its coefficient in free flow and submerged conditions. In the present study, an experimental investigation has been conducted on new type of Lopac gate called elliptical lopac gates. This type of gate, which is a combination of rectangular Lopac gates and elliptical sharp edges have good function in passage of rubbish, foliage of trees and sediments along with the flow. We constructed and installed an elliptical Lopac gate as well as a rectangular Lopac gate at the laboratory scale to control and compare performance of both types of gates. The test were conducted for 5 opening degrees and for 5 discharge. Then, discharge equations of the elliptical Lopac gate in free flow condition with the help of buckingham pi theorem were presented with appropriate precision of Mean Absolute Percentage Error (MAPE = 4.44%).Also, changes in the energy flow dissipation crossing of Elliptical Lopac gate and Rectangular Lopac gate were studied and compared.

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References

1-Anouymous, 2013. Leaders in water management and control. Available from: http:// www.as2i.net /products/ control-gates/hydra-lopac-gate.
 
2- Aqua Systems 2000 Incorporation (AS21). 2013 Leaders in Water Management and Control , Available from :http://www.as2i.net/products/control-gates/hydra-lopac-gate [10september2013]
 
3- Babaei Faghih Mahaleh, R., Smaielie Varakei, M. and Shafiei Sabet, B., 2018. Investigation of the effect of geometry characteristics and hydraulic conditions on the discharge control structure as lopac gate – Parshal flume. Iranian Journal of Soil and Water Research, 49(4), pp.711-727. (In Persian).
 
4- Cox, A.L., Kullberg, E.G., MacKenzie, K.A. and Thornton, C.I., 2014. Stage-discharge rating equation for an elliptical sharp-crested weir. Journal of Irrigation and Drainage Engineering, 140(6), 04014018.
 
5- Cox, A.L., Saadat, S., MacKenzie, K.A. and Thornton, C.I., 2015. Effect of urban debris on hydraulic efficiency of an elliptical sharp-crested weir. Journal of Irrigation and Drainage Engineering, 141(6), 06014006.
 
6- Langeman, P., Craig, K., Elser, P. and Allen, L., 2006. Irrigation gate system. US patent, 7, p.114..
 
7- Mahmoodian Shooshtari, M., 2010. Principles of flow in open channel. Chamran University of Ahvaz.
 
8- Naghaei, R. and Monem, M.J., 2013a. Definition of lopac gate for control of water level in irrigation canals and presentation of hyroulic equation. In 4th National Irrigation and Drainage Management Conference, Shahid Chamran University of Ahvaz, Ahvaz, Iran. (In Persian).
 
9- Naghaei, R. and Monem, M.J., 2013b. Introducing various hydraulic and operation conditions of Lopac gate in irrigation canals. In 1st National Conf. on Irrigation and Agricultural Water Productivity,Iranian Association of Irrigation and Drainage, Tehran, Iran. (In Persian).
 
10- Naghaei, R. and Monem, M.J., 2016. Development of a mathematical model of Lopac gates in accordance with the ICSS hydrodynamic model. Journal of Irrigation and Drainage Engineering, 142(10), p.04016043.
 
11- Oad, R. and Kinzli, K., 2006. Employed in middle rio grand vally to help deliver water efficiently. Available from: http://www.as2i .net/products/control-gates.
 
12- Yousefvand, F., 2015. Experimental investigation on the effect of hydraulic and operating conditions on the performance of lopac gates. MSc. Thesis, Tarbiat Modares University of Tehran, Iran. (In Persian).
 
13- Yousefvand, F and Monem, M.J., 2014. Definition of lopac gate and presentation of hyroulic equation in free flow conditions. In 13th Irrigation Hydraulic Conference, Tabriz University, Tabriz, Iran. (In Persian).
 
14- Yousefvand, F., Monem, M.J. and Kavian pour, M.R., 2015. Analitical and Experimental evaluation of discharge coefficient of lopac gates in submerge condition. Iranian Journal of irrigation and drainage, 5(9), pp.811-819. (In Persian).
 
15- Yousefvand, F., Monem, M.J. and Kavian pour, M.R., 2018. Estimate of flow equation and discharge coefficient of lopac gates in submerge condition. Iranian Water Researches Journal, 12(2),pp.51-58 (In Persian).
Irrigation Sciences and Engineering
Volume 46, Issue 2
September 2023
Pages 91-101

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History

  • Receive Date: 03 June 2019
  • Revise Date: 31 January 2020
  • Accept Date: 03 February 2020
  • Publish Date: 23 August 2023

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