Prediction of Discharge Capacity of Labyrinth Weir with Gene Expression Programming

This paper proposes a model based on gene expression programming for predicting discharge coefficient of triangular labyrinth weirs. The parameters influencing discharge coefficient prediction were first examined and presented as crest height ratio to the head over the crest of the weir (p/y), crest length of water to channel width (L/W), crest length of water to the head over the crest of the weir (L/y), Froude number (F=V/√(gy)) and vertex angle () dimensionless parameters. Different models were then presented using sensitivity analysis in order to examine each of the dimensionless parameters presented in this study. In addition, an equation was presented through the use of nonlinear regression (NLR) for the purpose of comparison with GEP. The results of the studies conducted by using different statistical indexes indicated that GEP is more capable than NLR. This is to the extent that GEP predicts the discharge coefficient with an average relative error of approximately 2.5% in such a manner that the predicted values have less than 5% relative error in the worst model.

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Determination Discharge Capacity of Triangular Labyrinth Side Weir Using Multi-Layer Neural Network (ANN-MLP)

Current World Environment ◽

10.12944/cwe.10.special-issue1.16 ◽

2015 ◽

Vol 10 (Special-Issue1) ◽

pp. 111-119 ◽

Cited By ~ 3

Author(s):

Sohrab Karimi ◽

Hossein Bonakdari ◽

Azadeh Gholami

Keyword(s):

Discharge Capacity ◽

Discharge Coefficient ◽

Vertex Angle ◽

Hydraulic Parameters ◽

Side Weir ◽

Dimensionless Parameters ◽

Weir Height ◽

Crest Length ◽

Side Weirs ◽

Mlp Model

statistic indexes have been used to assess the accuracy of the results. The results of the examinations indicate that using MLP model along with simultaneous use of dimensionless parameters for the purposes of estimating discharge coefficient: the ratio of water behind the weir to the channel width (h/b), ratio of weir crest length to weir height (L/W), relative Froude number (F=V/√(2Side weirs are used in open channels to control flood and the flow passing through it. Discharge capacity is one of the crucial hydraulic parameters of side weirs. The aim of this study is to determine the effect of the intended dimensionless parameters on predicting the discharge coefficient of triangular labyrinth side weir. MAPE, RMSE, and Rgy)) and vertex angle (ϴ), offered the best results (MAPE= 0.67, R2= 0.99, RMSE = 0.009) in comparison with other models.

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Discharge coefficients for ogee weirs including the effects of a sloping upstream face

Water Science & Technology Water Supply ◽

10.2166/ws.2020.064 ◽

2020 ◽

Vol 20 (4) ◽

pp. 1493-1508 ◽

Cited By ~ 1

Author(s):

Farzin Salmasi ◽

John Abraham

Keyword(s):

Gene Expression ◽

Experimental Data ◽

Regression Analysis ◽

Discharge Coefficient ◽

Gene Expression Programming ◽

Linear Interpolation ◽

Performance Criteria ◽

Upstream Face ◽

Discharge Coefficients ◽

Regression Techniques

Abstract Discharge coefficients (C0) for ogee weirs are essential factors for predicting the discharge-head relationship. The present study investigates three influences on the C0: effect of approach depth, weir upstream face slope, and the actual head, which may differ from the design head. This study uses experimental data with multiple non-linear regression techniques and Gene Expression Programming (GEP) models that are applied to introduce practical equations that can be used for design. Results show that the GEP method is superior to the regression analysis for predicting the discharge coefficient. Performance criteria for GEP are R2 = 0.995, RMSE = 0.021 and MAE = 0.015. Design examples are presented that show that the proposed GEP equation correlates well with the data and eliminates linear interpolation using existing graphs.

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Using data mining methods to improve discharge coefficient prediction in Piano Key and Labyrinth weirs

Water Science & Technology Water Supply ◽

10.2166/ws.2021.304 ◽

2021 ◽

Author(s):

Mahdi Majedi-Asl ◽

Mehdi Foladipanah ◽

Venkat Arun ◽

Ravi Prakash Tripathi

Keyword(s):

Discharge Coefficient ◽

Gene Expression Programming ◽

Research Work ◽

Coefficient Of Determination ◽

Support Vector ◽

Effective Parameters ◽

Data Set ◽

Labyrinth Weir ◽

Dimensional Parameters ◽

Using Data

Abstract As a remarkable parameter, the discharge coefficient (Cd) plays an important role in determining weirs' passing capacity. In this research work, the support vector machine (SVM) and the gene expression programming (GEP) algorithms were assessed to predict Cd of piano key weir (PKW), rectangular labyrinth weir (RLW), and trapezoidal labyrinth weir (TLW) with gathered experimental data set. Using dimensional analysis, various combinations of hydraulic and geometric non-dimensional parameters were extracted to perform simulation. The superior model for the SVM and the GEP predictor for PKW, RLW, and TLW included , and respectively. The results showed that both algorithms are potential in predicting discharge coefficient, but the coefficient of determination (RMSE, R2, Cd(DDR)max) illustrated the superiority of the GEP performance over the SVM. The results of the sensitivity analysis determined the highest effective parameters for PKW, RLW, and TLW in predicting discharge coefficients are , , and Fr respectively.

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Energy Dissipation and Hydraulics of Flow over Trapezoidal–Triangular Labyrinth Weirs

Water ◽

10.3390/w12071992 ◽

2020 ◽

Vol 12 (7) ◽

pp. 1992 ◽

Cited By ~ 5

Author(s):

Amir Ghaderi ◽

Rasoul Daneshfaraz ◽

Mehdi Dasineh ◽

Silvia Di Francesco

Keyword(s):

Energy Dissipation ◽

Discharge Coefficient ◽

Residual Energy ◽

Free Flow ◽

Flow Conditions ◽

Labyrinth Weir ◽

Sidewall Angle ◽

Weir Height ◽

Downstream Flow ◽

Labyrinth Weirs

In this work experimental and numerical investigations were carried out to study the influence of the geometric parameters of trapezoidal–triangular labyrinth weirs (TTLW) on the discharge coefficient, energy dissipation, and downstream flow regime, considering two different orientations in labyrinth weir position respective to the reservoir discharge channel. To simulate the free flow surface, the volume of fluid (VOF) method, and the Renormalization Group (RNG) k-ε model turbulence were adopted in the FLOW-3D software. The flow over the labyrinth weir (in both orientations) is simulated as a steady-state flow, and the discharge coefficient is validated with experimental data. The results highlighted that the numerical model shows proper coordination with experimental results and also the discharge coefficient decreases by decreasing the sidewall angle due to the collision of the falling jets for the high value of H/P (H: the hydraulic head, P: the weir height). Hydraulics of flow over TTLW has free flow conditions in low discharge and submerged flow conditions in high discharge. TTLW approximately dissipates the maximum amount of energy due to the collision of nappes in the upstream apexes and to the circulating flow in the pool generated behind the nappes; moreover, an increase in sidewall angle and weir height leads to reduced energy. The energy dissipation of TTLW is largest compared to vertical drop and has the least possible value of residual energy as flow increases.

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A New Approach to Estimate the Discharge Coefficient in Sharp-Crested Rectangular Side Orifices Using Gene Expression Programming

Advances in Intelligent Systems and Computing - Intelligent Computing ◽

10.1007/978-3-030-52243-8_7 ◽

2020 ◽

pp. 77-96

Author(s):

Hossein Bonakdari ◽

Bahram Gharabaghi ◽

Isa Ebtehaj ◽

Ali Sharifi

Keyword(s):

Gene Expression ◽

Discharge Coefficient ◽

Gene Expression Programming ◽

New Approach

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Determining discharge coefficient of labyrinth and arced labyrinth weirs using support vector machine

Hydrology Research ◽

10.2166/nh.2017.214 ◽

2017 ◽

Vol 49 (3) ◽

pp. 924-938 ◽

Cited By ~ 10

Author(s):

Kiyoumars Roushangar ◽

Mohammad Taghi Alami ◽

Jalal Shiri ◽

Mahdi Majedi Asl

Keyword(s):

Support Vector Machine ◽

Support Vector ◽

Plan View ◽

Labyrinth Weir ◽

Discharge Coefficients ◽

Magnification Ratio ◽

Crest Length ◽

Labyrinth Weirs ◽

Influential Parameters ◽

Water Ratio

Abstract A labyrinth weir is a linear weir folded in plan-view which increases the crest length and the flow rate for a given channel width and an upstream flow depth. The present study aimed at determining discharge coefficients of labyrinth and arced labyrinth weirs using support vector machine (SVM)-based models. A total of 527 laboratory test data of four types of weirs, namely, Normal and Inverted orientation Labyrinth Weirs in flume (NLW, ILW) and Arced Labyrinth Weirs with and without nappe Breakers in reservoir (ALW, ALWB), were captured from the published literature and utilized to feed the SVM-based models. The obtained results revealed the capability of the SVM-based models in determining discharge coefficients. The results showed that the SVM-based model of arced labyrinth weir (ALW) produced the most accurate results when three dimensionless parameters, e.g. (HT/P) head water ratio, (α/θ) angle ratio and (Lc/W) magnification ratio, were introduced as input parameters (Root mean square error [RMSE]= 0.013 and R2 = 0.970 for the test stage). Nonetheless, sensitivity analysis showed that Froude number and head water ratio are the most influential parameters on discharge coefficients of the labyrinth and arced labyrinth weirs, respectively.

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Discussion of “Gene expression programming analysis of implicit Colebrook–White equation in turbulent flow friction factor calculation” by Saeed Samadianfard [J. Pet. Sci. Eng. 92-93 (2012), 48-55]

10.31219/osf.io/zpr2e ◽

2017 ◽

Author(s):

Dejan Brkić ◽

Brkic Dejan

Keyword(s):

Gene Expression ◽

Turbulent Flow ◽

Friction Factor ◽

Relative Error ◽

Energy Security ◽

Gene Expression Programming ◽

Security Systems ◽

Flow Friction ◽

Programming Analysis ◽

Maximal Relative Error

Maximal relative error of the explicit approximation to the Colebrook equation for flow friction presented in the discussed paper by Saeed Samadianfard [J. Pet. Sci. Eng. 92-93 (2012), 48-55; doi. 10.1016/j.petrol.2012.06.005] is investigated. Samadianfard claims that his approximation is very accurate with the maximal relative error of no more than 0.08152%. Here is shown that this error is about 7%. Related comments about the paper are also enclosed. ; JRC.F.3-Energy Security, Systems and Market

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