Experimental Assessment of the effect of positive Variation of weir in cross section on discharge coefficient of triangle weirs structures

Document Type : Complete scientific research article

Authors

1 null

2 Faculty Member

3 student of gorgan university of agricultural science and natural resources

Abstract

Background and Objectives: Weirs are always one of the most important components of water transmission networks, due to its simple structure and function. These components play an important role in the hydraulic structures by regulating the water surface, measuring the flow discharge and increasing the water level. And as a result, provide water heights needed to divert the desired flow into the lateral channels. Also, these structures are used as flow measuring devices of the important applications of overflows, the secure flow of floods behind the dams. The purpose of this study is to investigate the investigation the effect of positive Variation of weir in cross section on discharge coefficient of triangle weirs structures and provide a relationship for estimating the discharge coefficient based on geometrical hydraulic parameters.
Materials and Methods: The discharge coefficient was defined as a function of Froude number (Fr), angle of vertex, ratio of water head to height of weir (H/P) and ratio of water head to effective length (H/Le). To achieve this aim, several experiments were done in the water and sediment laboratory, located in Gorgan agricultural sciences and natural resources university . The experiments were accomplished by 4 different angles of vertexes and 3 different slopes. Then, an equation was set by using Gene Expression Programming (GEP) to estimate the discharge coefficient by more accuracy.
Result:The findings showed that the discharge coefficient would decrease by increasing trend in the side slopes in the constant Froude number. Also, by increasing the ratio of H/P a decreasing and increasing trend in the discharge coefficient was seen, respectively. The results show that GEP predicted the coefficient of triangle weirs structures with R2 of 0.9676 and 0.8591 and RMSE of 0.0706 and 0.0247 for training and testing stages, respectively. This model gave better results compared by regression equation with R2 of 0.9253 and 0.8029 and RMSE of 0.0467 and 0.084 for training and testing parts, respectively. In the other words, the error of coefficient triangle weirs structures prediction was decreased about 47.10% using GEP approach.
Conclusion: The results show that GEP intelligence approach is an adequate model to coefficient triangle weirs structures. Also, the results of traditional regression equations were improved using this method. In the other words, these results indicated that GEP is reliable to evaluate the coefficient discharge of triangle weirs structures by more accurate estimation. So; use of this way is suggested in future studies related to this topic.

Keywords

References

1.Azamathulla, H.M. 2012. Gene expression programming for prediction ofscout depthdownstream of sills. J. Hydol.460-461: 156-159.
2.Carollo, F.G., Ferro, V., and Pampalone,V. 2017. Testing the Outflow Processover a Triangular Labyrinth Weir. J. Irrig.Drain. Engin. 143: 8. 06017007.
3.Ebtehaj, I., Bonakdari, H., Zaji,A.H., Azimi, H., and Sharifi, A. 2015.Gene expression programming to predictthe discharge coefficient in rectangularside weirs. Applied Soft Computing.35: 618-628.
4.Corkson, B., and Tullis, B.P. 2012. Arcedlabyrinth weirs. J. Hydr. Engin. 138: 555-562.
5.Emamgholizadeh, S., Bateni, S.M., Shahsavani, D., Ashrafi, T., andGhorbani, H. 2015. Estimation of soilcation exchange capacity using GeneticExpression Programming (GEP) andMultivariate Adaptive Regression Splines(MARS). J. Hydrol. 529: 1590-1600.
6.Emiroglu, M., and Baylar, A. 2005.Influence of included angle and sillslope on air entrainment of Triangularplanform Labyrinth Weir. J. Hydr. Engin.131: 184-189.
7.Ferreira, C. 2001a. Gene ExpressionProgramming in Problem Solving. In: 6thonline world conference on SoftComputing in Industrial Applications(Invited tutorial), Pp: 1-22.
8.Ferreira, C. 2001b. Gene ExpressionProgramming. A New Adaptive Algorithmfor Solving Problems. Complex Systems.13: 2. 87-129.
9.Ferreira, C. 2004. Gene expressionprogramming and the evolution ofcomputer programs. Recent Developmentsin Biologically Inspired Computing,Pp: 82-103.
10.Ghaderi, A., Danesh Afza, R., andDesineh, M. 2015. The effect of creatinga positive slope edge labyrinth weir ondischarge coefficient and discharge ratethe. 4th. International Congress on Civil
Engineering, Architecture and UrbanDevelopment 27-29 December 2016.Shahid Beheshti University. Tehran. Iran.
11.Ghodsian, M. 2009. Stage-dischargerelationship for a triangular labyrinthspillway. Proceedings of the ICE-WaterManagement. 1: 62. 173-178.
12.Gupta, K.K., Kumar, S., and Ahmad, Z.2014. An approach to analyze the flowcharacteristics of sharp-crested triangularplatform contracted weirs. World Appl.Sci. J. 32: 7. 1311-1317.
13.Guven, A., and Ersin Talu, N.2010. Gene expression programmingfor estimating suspended sediment yieldin middle Uuphratesbasin. Clean-Soil,AirWater. 38: 12. 1159-1168.
14.Hay, N., Taylor, G. 1970. Performanceand desinge of labyrinth weirs. J.Hydraul. Div. 96: 2337-2357.
15.Jamifar, F., Takavandi, A., MaghforMaghreebi, M., and Bina, K. 2015.Investigate the effect of vertex angle onhydraulic performance of Triangularlabyrinth weir. 3th International Congress
on Civil Engineering, Architecture,Urban Development. 29-31 Decmber.Shahid Beheshti University. Tehern. Iran.
16.Mohebbi, M., Meftah Halaghi, M.,Dehghani, A., and Zahiri, A. 2015.Experimental Study of DischargeCoefficient of Triangular-in-planweir structure. 5th National ConferenceSustainable Architecture, 15 July. Instituteof Higher Education Mehravand. Theran.
17.Oskouei, M., Emadi, A.R., andShahnazari, A. 2016. Investigation ofsimultaneous slope of upstream anddownstream ramps on hydraulicperformance of rectangular labyrinthweir. J. Water Soil Cons. 23: 4. 155-169.
Journal of Water and Soil Conservation
Volume 26, Issue 1
May and June 2019
Pages 233-246

Files

Share

How to cite

Statistics