This paper reports the computational fluid dynamics and experimental fluid dynamics studies conducted for the measurement of release by a composite broad-crested (CBC) weir. Studies conducted thus far depict that manufacturing composite weirs for precise discharge measurement is a demanding field. The performance of composite broad crested weirs as flow measuring devices depends on the weir width (b), height of the weir and upstream flow over the weir crest (h). Thus, a change in the geometry of the weir for a given flume will determine the flow characteristics, mainly the discharge coefficient (Cd), which changes according to the h/b ratio. At present, researchers have maintained an average range of Cd for various h/b ratios. This study is related to CFD investigations regarding hydraulic properties to determine optimized weir geometry. FLOW 3D deploys accuracy in free surface simulations where the model employs a renormalized group (RNG) approach with volume of fluid (VOF). To validate the CFD model, laboratory models were used. In this research, flow depth parameters on the weir crest and velocity distribution on a composite broad-crested weir were evaluated. The experimental observations were used to validate the 3-D CFD models, and then the geometry of the composite broad-crested weir was optimized to obtain a constant Cd. The results of both the performance of the CBC weir for precise measurement of a wide range of discharges are confirmed by numerical models and experimental observations by fairly maintaining a constant design input value of the discharge coefficient of 0.6. Compared to empirical methods, optimization of the weir geometry through CFD definitely yields the correct model prediction. Furthermore, additive manufacturing of this optimized model with poly lactic acid plastic material validated the weir performance with accurate estimations between theoretical, experimental, and CFD outputs. The applications of the proposed method from the energy aspect are highlighted.


Composite Broad Crested Weir, Coefficient of Discharge, Flow 3D, 3D printer, Energy

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ACKERS P., WHITE W.R., HARRISON A.J.M. (1978). Weirs and flumes for flow measurement, Wiley, New York, USA.

AMIR HOSSEIN A., RAJARATNAM N. (2009). Discharge characteristics of weirs of finite crest length, Journal of Hydraulic Engineering, Vol. 135, Issue 12, pp. 1081-1085.

ACHOUR B., AMARA L. (2022). Accurate discharge coefficient relationship for the crump weir, Larhyss Journal, No 52, pp. 93-115.

ACHOUR B., AMARA L., MEHTA D., BALAGANESAN P. (2022a). Compactness of Hydraulic Jump Rectangular Stilling Basins Using a Broad-Crested Sill, Larhyss Journal, No. 51, pp. 31-41.

ACHOUR B., AMARA L., MEHTA, D. (2022b). Control of the hydraulic jump by a thin crested sill in a rectangular channel, new experimental consideration, Larhyss Journal, No 50, pp. 31-48.

ACHOUR B., AMARA L., MEHTA, D. (2022c). New theoretical considerations on the gradually varied flow in a triangular channel, Larhyss Journal, No. 50, pp. 7-29.

AZAMATHULLA H.M., HAGHIABI A.H., PARSAIE A. (2016). Prediction of side weir discharge coefficient by support vector machine technique, Water Science and Technology: Water Supply, Vol. 16, Issue 4, pp. 1002-1016.

BIJANKHAN M., Di STEFANO C., FERRO V., KOUCHAKZADEH S. (2014). New stage discharge relationship for weirs of finite crest length, Journal of Irrigation and Drainage Engineering, Vol. 140, Issue 3, 06013006.

BILHAN O., AYDIN M.C., EMIROGLU M.E., MILLER C.J. (2018). Experimental and CFD Analysis of Circular Labyrinth Weirs, Journal of Irrigation and Drainage Engineering, ASCE, Vol. 144, Issue 6, 04018007.

BOITEN W., PITLO H.R. (1982). The V- shaped broad-crested weir, Journal of Irrigation and Drainage Engineering, Vol. 108, Issue 2, pp. 142-160.

BOS M.G. (1989). Discharge Measurement Structures. 3rd edition, International Institute for Land Reclamation and Improvement, Publication 20, Wageningen, The Netherlands.

FARZIN SALMASI, SANAZ POORESCANDAR, ALI HOSSEINZADEH DALIR, DAVOOD FARSADI ZADEH, 2012. Discharge relations for rectangular broad crested weirs, Journal of Agricultural Sciences, No 17, pp. 324-336.

GOGUS M., DEFNE Z., OZKANDEMIR V. (2006). Broad-crested weirs with rectangular compound cross sections, Journal of Irrigation and Drainage Engineering, Vol. 132, Issue 3, pp. 272–280.

HAGER W.H., SCHWALT M. (1994). Broad – crested weir, Journal of Irrigation and Drainage Engineering, Vol. 120, Issue 1, pp. 13 - 25.

HARRISON A.J.M. (1967). The streamlined broad-crested weir, Proceedings of the Institution of Civil Engineers, Vol. 38, pp. 657-678.

HINGE G.A., BALKRISHNA S., KHARE K.C. (2010). Improved Design of Stilling Basin for Deficient Tail Water, Journal of Basic and Applied Scientific Research, Vol. 1, Issue 1, pp. 31-40.

HINGE G.A., BALKRISHNA S., KHARE K.C. (2011). Experimental and Numerical Study of Compound Broad Crested Weir, International Journal of Fluids Engineering, Vol. 3, Issue 2, pp. 197-202.

HORTON R.E. (1907). Weir experiments, coefficients, and formulas, Dept. of the Interior, U.S. Geological Survey, Water-Supply and Irrigation Paper 200. Government Printing Office, Washington, D.C.

ISSAM A. AL-KHATIB, MUSTAFA GOGUS (2014). Prediction models for discharge estimation in rectangular compound broad-crested weirs, Flow Measurement and Instrumentation, Vol. 36, pp. 1-8.

KHAN L.A., WICKLEIN E.A., TEIXEIRA E.C. (2006). Validation of a Three-Dimensional Computational Fluid Dynamics Model of a Contact Tank, Journal of Hydraulic Engineering, American Society of Civil Engineers, ASCE, Vol. 132, Issue 7, pp. 741- 746.

KINDSVATER C.E., CARTER R.W. (1959). Discharge Characteristics of Rectangular Thin-Plate Weirs, Paper No 3001, Transactions, American Society of Civil Engineers, ASCE, No 124.

KULIN G., COMPTON P.R. (1975). A Guide to Methods and Standards for the Measurement of Water Flow, Special Publication 421, National Bureau of Standards.

KULKARNI K.H., HINGE G.A. (2017). Compound Broad Crested Weir for Measurement of Discharge – A Novel Approach, Proceedings, International Conference organized by Indian Society of Hydraulics – ISH HYDRO. 21 – 23 Dec 2017, India, pp. 678 – 687.

KULKARNI K.H., HINGE G.A. (2020). Experimental study for measuring discharge through compound broad crested weir, Flow Measurement and Instrumentation. Elsevier, Vol. 75, Paper 101803.

KULKARNI K.H., HINGE G.A. (2021). Performance Enhancement in Discharge Measurement by Compound Broad Crested Weir with Additive Manufacturing.Larhyss Journal, No 48, pp. 169-188.

KULKARNI K.H., HINGE G.A. (2021). Comparative study of experimental and CFD analysis for predicting discharge coefficient of compound broad crested weir. Water Supply – Water Science and Technology, IWA Publishing, Vol 22, No 3, pp. 3283-3296.

MUSTAFA GOGUS, ISSAM A. AL-KHATIB, AHMET E. ATALAY, JUMANA I. KHATIB (2016). Discharge prediction in flow measurement flumes with different downstream transition slopes, Flow measurement and Instrumentation, Vol. 47, pp. 28-34.

PARSAIE, A., AZAMATHULLA, H.M., HAGHIABI, A.H. (2018). Prediction of discharge coefficient of cylindrical weir–gate using GMDH-PSO, ISH Journal of Hydraulic Engineering, Vol. 24, Issue 2, pp. 116-123.

RANGA RAJU K.G. (1981). Flow through open channels, McGraw-Hill, New York.

REDA M. ABD EL-HADY RADY (2011). 2D 3D Modeling of flow over sharp crested weir, Journal of Applied Sciences Research, Vol. 7, Issue 12, pp. 2495-2505.

SAFARZADEH A., MOHAJERI S.H. (2018). Hydrodynamics of Rectangular Broad-Crested Porous Weir, Journal of Irrigation and Drainage Engineering, ASCE, Vol. 144, Issue 10, 04018028

SAMADI A., ARVANAGHI H. (2014). CFD Simulation of Flow over Contracted compound Arched Rectangular Sharp Crested Weirs, International Journal of Optimization in Civil Engineering, Vol. 4, Issue 4, pp. 549-560.

SAVAGE B.M., JOHNSON M.C. (2001). Flow Over Ogee Spillway: Physical and Numerical Model Case Study, Journal of Hydraulic Engineering, ASCE, Vol. 127, Issue 8, pp. 640-649.

SWAMEE P.K. (1988). Generalized rectangular weir equations, Journal of Hydraulic Engineering, ASCE, Vol. 114, Issue 8, pp. 945–952.

The United States Bureau of Reclamation (USBR) Water Measurement Manual, Chapter 7 – Weirs. U.S. Government Printing Office, Washington, DC 20402. 2001. Retrieved from http://www/

ZAHIRI A., AZAMATHULLA H.M. (2014). Comparison between linear genetic programming and M5 tree models to predict flow discharge in compound channels, Neural Computing and Application, Vol. 24, No. 2, pp. 413-420.


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