Experimental Study on the Flow Characteristics of ￢-Type Groyne
- 1
- 2
Abstract
A hydraulic model test for ￢-type groynes (with “￢” shape) was conducted to analyze the flow characteristics around these groynes. The results of the model tests are expected to be used as fundamental information in designing the ￢-type groyne constructed in the field. Main hydraulic factors such as velocity and thalweg line changes in the main channel and separation area were analyzed in this study. The thalweg line is a stream line where the maximum velocity occurs, whereas the separation area is the boundary between the main flow and the recirculation zone. Model tests with 5 different arm lengths of the ￢-type groynes were conducted by changing the velocity. The LSPIV (Large-Scale Particle Image Velocimetry) technique was used to measure and analyze flow variation around the ￢-type groynes. The velocity in the main channel measured to be increased by 1.5 times. The velocity variation on groyne arm length is little. The width of the thalweg lines (<i>T<sub>CL</sub></i>) was changed to 55 - 57% of the channel width. The Froude number did not affect the thalweg line (<i>T<sub>CL</sub></i>) and separation line (<i>S<sub>h</sub></i>) changes, however.
- J. R. Francis, A. Pattanick and S. Wearne, “Observations of Flow Patterns around Some Simplified Groyne Structures in Channels,” Technical Note No. 8, Proceedings of Institution of Civil Engineers, London, December 1968, pp. 829-846.
- N. Rajaratnam and B. Nwachukwu, “Flow Near Groyne- Dike Structures,” Journal of the Hydraulics Division, ASCE, Vol. 109, No. HY3, 1983, pp. 463-480. doi:10.1061/(ASCE)0733-9429(1983)109:3(463)
- T. Tingsanchali and S. Maheswaran, “2D Depth-Averaged Flow Computation Near Groyne,” Journal of Hydraulic Engineering, ASCE, Vol. 116, No. 1, 1990, pp. 71-86. doi:10.1061/(ASCE)0733-9429(1990)116:1(71)
- R. Ettema and M. Muste, “Scale Effects in Flume Experiments on Flow around a Spur Dike in Flatbed Channel,” Journal of Hydraulic Engineering, ASCE, Vol. 130, No. 7, 2004, pp. 635-646. doi:10.1061/(ASCE)0733-9429(2004)130:7(635)
- W. S. J. Uijttewaal, “Effects of Groyne Layout on the Flow in Groyne Fields: Laboratory Experiments,” Journal of Hydraulic Engineering, ASCE, Vol. 131, No. 9, 2005, pp. 782-791. doi:10.1061/(ASCE)0733-9429(2005)131:9(782)
- J. G. Kang, H. K. Yeo and S. J. Kim, “An Experimental Study on Tip Velocity and Downstream Recirculation Zone of Single Groyne Conditions,” KWRA, Vol. 38, No. 2, 2005, pp. 143-153
- H. K. Yeo, Y. S. Roh, J. G. Kang and S. J. Kim, “Varia-tions of Flow Thalweg Alignment and Separation Region around a Groyne,” KWRA, Vol. 39, No. 4, 2006, pp. 313-320.
- M. P. Lloyd, et al., “Unsteady Surface-Velocity Field Measurement Using Particle Tracking Velocimery,” Journal of Hydraulic Research, Vol. 33, No. 4, 1995, pp. 519-534. doi:10.1080/00221689509498658
- I. Fujita, et al., “Large-Scale Particle Image Velocimetry for Flow Analysis in Hydraulic Applications,” Journal of Hydraulic Research, Vol. 36, No. 3, 1998, pp. 397-414. doi:10.1080/00221689809498626
- M. Muste, et al., “Large-Scale Particle Image Velocimetry: A Reliable Tool for Physical Modeling,” Pro- ceedings of ASCE 2000 Joint Conference on Water Re- sources Engineering and Water Re-sources Planning & Management, Minneapolis, 30 July-2 Au-gust 2000.