Experimental studies and model development of flow over Arched Labyrinth Weirs using GMDH method

Arched labyrinth weir is a special type of weir in which the crest length is increased by arch action with/without providing notches. Effects of various parameters on the coefficient of discharge of the arched labyrinth weir are established using experimental data obtained in the present study. A comparative study of discharge for different crest lengths of weir has also been presented. A new model is developed for coefficient of discharge of the arched labyrinth weir using the non-linear regression method (R = 0.8951, MAPE = 7.6037 AAD = 7.5997 and RMSE = 0.0509). Generalized models for predicting the coefficient of discharge using GMDH network have also been developed. The prediction based on the GMDH model (R = 0.9691, MAPE = 3.9453.6037 AAD = 3.7035 and RMSE = 0.0283) is more satisfactory than those given by traditional regression equations. Flow pattern in the vicinity of main channel of upstream of the arched labyrinth weir is also observed.