World Environmental and Water Resources Congress 2020
An Experimental Study: Effects of Boulder Spacing on Mean and Turbulent Flow Characteristics
Publication: World Environmental and Water Resources Congress 2020: Hydraulics, Waterways, and Water Distribution Systems Analysis
ABSTRACT
An experimental study was conducted to investigate effect of adding boulders with different boulder spacing (8D, 6D, and 4D) on mean and turbulent flow characteristics. Measurement points were selected at centerline and side of the flume. Mean flow depth did not vary significantly in different scenarios but mean streamwise velocity decreased at centerline after adding boulders especially at shorter spacing. It appeared flow regime for all of the scenarios is isolated-roughness flow. For centerline points, root-mean squared velocity, turbulent kinetic energy, and turbulence intensity increased after adding boulders and by decreasing boulder spacing however, integral scale parameters decreased after adding boulders and did not change significantly by decreasing boulder spacing. Also, relationships between time-averaged streamwise velocity and normalized turbulence intensity was found for each scenario.
Get full access to this article
View all available purchase options and get full access to this chapter.
REFERENCES
Baki, A.B.M., Zhu, D.Z., and Rajaratnam, N. (2014). Mean flow characteristics in a rock-ramp-type fish pass. Journal of Hydraulic Engineering 140(2), 156–168.
Baki, A.B.M., Zhu, D.Z. and Rajaratnam, N., 2015. Turbulence characteristics in a rock-ramp-type fish pass. Journal of Hydraulic Engineering, 141(2), p.04014075.
Baki, A.B.M., Zhang, W., Zhu, D.Z., and Rajaratnam, N. (2016). Flow Structures in the Vicinity of a Submerged Boulder within a Boulder Array. Journal of Hydraulic Engineering 143(5), 04016104.
Dey, S., Sarkar, S., Bose, S.K., Tait, S., and Castro-Orgaz, O. (2011). Wall-wake flows downstream of a sphere placed on a plane rough wall. Journal of Hydraulic Engineering 137(10), 1173–1189.
Goring, D.G., and Nikora, V.I. (2002). Despiking acoustic Doppler velocimeter data. Journal of Hydraulic Engineering 128(1), 117–126.
Fang, H.W., Liu, Y., and Stoesser, T. (2017). Influence of Boulder Concentration on Turbulence and Sediment Transport in Open-Channel Flow over Submerged Boulders. Journal of Geophysical Research: Earth Surface 122(12), 2392–2410.
Lacey, R.W.J., and Roy, A.G. (2008). The spatial characterization of turbulence around large roughness elements in a gravel-bed river. Geomorphology 102(3), 542–553.
Lacey, R.J. and Rennie, C.D., 2011. Laboratory investigation of turbulent flow structure around a bed-mounted cube at multiple flow stages. Journal of Hydraulic Engineering, 138(1), pp.71-84.
Marriner, B.A., Baki, A.B., Zhu, D.Z., Cooke, S.J. and Katopodis, C., 2016. The hydraulics of a vertical slot fishway: A case study on the multi-species Vianney-Legendre fishway in Quebec, Canada. Ecological Engineering, 90, 190-202.
Papanicolaou, A.N., Diplas, P., Dancey, C.L., and Balakrishnan, M. (2001). Surface Roughness Effects in Near-Bed Turbulence: Implications to Sediment Entrainment. Journal of Engineering Mechanics 127(3), 211–218.
Papanicolaou, A.N., Kramer, C.M., Tsakiris, A.G., Stoesser, T., Bomminayuni, S., and Chen, Z. (2012). Effects of a fully submerged boulder within a boulder array on the mean and turbulent flow fields: Implications to bedload transport. Acta Geophys. 60(6), 1502–1546.
Sadeque, M.F., Rajaratnam, N., and Loewen, M.R. (2009). Shallow turbulent wakes behind bed-mounted cylinders in open channels. Journal of Hydraulic Research 47(6), 727–743.
Sarkar, S., Papanicolaou, A.N. and Dey, S., 2016. Turbulence in a gravel-bed stream with an array of large gravel obstacles. Journal of Hydraulic Engineering, 142(11), p.04016052.
Information & Authors
Information
Published In
World Environmental and Water Resources Congress 2020: Hydraulics, Waterways, and Water Distribution Systems Analysis
Pages: 31 - 42
Editors: Sajjad Ahmad, Ph.D., and Regan Murray, Ph.D.
ISBN (Online): 978-0-7844-8297-1
Copyright
© 2020 American Society of Civil Engineers.
History
Published online: May 14, 2020
Published in print: May 14, 2020
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.