» Research Note « Evaluation of FLOW-3D Numerical Model in Predicting the Morphological Changes at River Junction

Document Type : Technical Note


Associate Professor, Dept. of Irrigation and Reclamation Engineering, University of Tehran, Karaj, Iran.


Due to hydraulic complexity in confluences, the study of different features of these locations such as sedimentation, erosion, and environmental considerations are of high interests to many researchers. Although many laboratory researches have been carried out regarding erosion and sedimentation in confluences, little researches have been done numerically. In this research the features and performance of FLOW-3D numerical model to simulate the flow, erosion, and sediment transport patterns in a junction of 2 canals with different flow rates and constant sediment flow, are investigated by comparing the results obtained from the numerical model with those obtained from a laboratory model. The widths of the canals of the physical model were 15 and 50 centimeters. The comparison between numerical and physical models shows an average of 6.3% error between maximum sediment depth in the junction of lateral and main canal between two models. Moreover, according to the measured results of erosion depth at the right bank of the main canal at the junction, the numerical model can estimate the erosion at the bank with the average of 26% error. Furthermore, the numerical model was able to predict the water surface profile of the flow in the junction with an average error of 1% when sediment was not injected.


صاحباری، ج. آ. و برقعی، س. م. (1387). "بررسی آزمایشگاهی الگوی فرسایش و رسوب گذاری در محل اتصال کانال ها". چهارمین کنگره ملی مهندسی عمران، دانشگاه تهران، ص.ص. 45-53.
قبادیان، ر.؛ شفاعی بجستان، م. و موسوی جهرمی، ح (1385). "بررسی آزمایشگاهی جدایی جریان در محل تلاقی رودخانه‌ها برای شرایط جریان زیر بحرانی". تحقیقات منابع آب ایران، 2، ص.ص. 67-77.
Baghlani, A. and Talebbeydokhti N. (2013). "Hydrodynamics of right-angled channel confluences by a 2D numerical model", Transactions of Civil Engineering, 32(C2), pp. 271-283.
Best, J. L. (1988). "Sediment transport and bed morphology at river channel confluences", Sedimentology, 35, pp. 481-498.
Chanson, H.(2004). The hydraulics of open channel flow: An introducion, Elsevier Butterworth-Heinemann.
De Serres, B., Roy, A.G., Biron, P.M. and Best, J.L. (1999). "Three-dimentional structure of flow at a confluence of river channel with discordant beds", Geomorphology, 26, pp. 313-335.
Flow Science Inc. (2005). “Flow-3D Help”, Version 9.0.
Fujita, I. and Komura, S. (1989). "Visualization of the flow at a confluence, in refined flow modelling and turbulence measurements", Edited by Universal Academy Press, International Association of Hydraulic Research, Tokyo, Japan.
Hsu, C.C., Wu, F.S. and Lee, W.J. (1998). "Flow at 90 equal-width open-channel junction", Journal of Hydraulic Engineering, ASCE, 124(2), pp. 186-191.
Huang, J., Weber, J.L., and Lai, G.Y. (2002). "Three dimensional numerical study of flows in open-channel junctions", Journal of Hydraulic Engineering, ASCE, 128(3), pp. 268-280
Khan, A.A., Cadavid, A. and Wang, S.S.Y. (2000). "Simulation of channel confluence and bifurcation using the CCHE2D model", Proc. Instn. Civ. Engrs. Water & Mar. Engng, 142(2), pp. 97-102.
Mosley, M.P. (1976). "An experimental study of channel confluences", Journal of Geology, 84(5), pp. 535-562.
Ribeiro, M. L. (2011). "Influence of tributary widening on confluence morphodynamics", PhD Thesis, Lausanne, Swiss.
Shabayek, S., Steffler, P., and Hicks, F. (2002). "Dynamic model for subcritical combining flows in channel junctions", Journal of Hydraulic Engineering, 128(9), pp. 821-828.
Shakibainia, A., Tabatabai, M. R. M., and Zarrati, A. R. (2010). "Three-dimensional numerical study of flow structure in channel confluences", Canadian Journal of Civil Engineering, 37, pp. 772-781.
Subramanya, K. (1982). Flow in open channels, Tata McGraw-Hill Education, 360 pages.
Webber, N.B., and Greated, C.A. (1966). "An investigation of flow behavior at the junction of rectangular channel", Proceeding Institution of Civil Engineers, 34, pp. 321-334.
Weber, L.J., Schumate E.D., and Mawer, N. (2001). "Experiments on flow at a 90° open-channel junction", Journal of Hydraulic Engineering., 127(5), pp. 340-350.
Weiming, W. (2001). "CCHE2D: sediment transport model (Version 2, 1)", Tech. Report No. NCCHE-TR-2001-3, NCCHE, University of Mississippi.
  • Receive Date: 17 February 2015
  • Revise Date: 31 May 2015
  • Accept Date: 07 October 2015
  • First Publish Date: 07 October 2015