Applied Research in Water Engineering

Applied Research in Water Engineering

Estimating the discharge coefficient of piano key weirs using soft computing models

Document Type : Original Article

Authors
Department of Hydraulic Structures Engineering, Faculty of Water and Environmental Engineering, Shahid Chamran University, Ahvaz, Iran.
Abstract
In this study, the discharge coefficient (Cd) of piano key weirs was estimated using the Support Vector Machine (SVM) model, and its performance was subsequently compared with the Multilayer Perceptron Neural Network (MLPNN) model. For this purpose, the parameters of the upstream head-to-weir height ratio (h⁄P), the inlet-to-outlet width ratio (w_i⁄w_o), the key length-to-width ratio (L_cy⁄w_cy), and the number of keys (N) were considered as inputs, with Cd as the output. The results indicated that the minimum value of the R2 statistical index and the maximum value of the RMSE for the mentioned models during the validation phase were R2=0.99 and RMSE=0.01, respectively. The developed MLPNN model consisted of two hidden layers, with four neurons in the first layer and two neurons in the second layer, both utilizing the sigmoid tangent activation function. The SVM model employed a radial basis function (RBF) kernel. Sensitivity analysis of the models revealed that the most influential parameters in modeling and estimating the discharge coefficient were h_o⁄P.
Keywords
Subjects

Volume 2, Issue 2
March 2024
Pages 239-248

  • Receive Date 03 February 2025
  • Revise Date 05 March 2025
  • Accept Date 15 March 2025