Laboratory and Numerical Investigation of Hyporheic Flow in Riffle-pool Bed Form | ||
| مجله اکوهیدرولوژی | ||
| Article 16, Volume 6, Issue 1, April 2019, Pages 191-204 PDF (1.39 M) | ||
| Document Type: Research Article | ||
| DOI: 10.22059/ije.2019.270596.992 | ||
| Authors | ||
| Neshat Movahedi1; Amir Ahmad Dehghani* 2; Nico Trauth3; Mehdi Meftah Halaghi2 | ||
| 1PhD Student, Department of Water and Soil, Gorgan University of Agricultural Sciences and Natural Resources | ||
| 2Associate Professor, Department of Water and Soil, Gorgan University of Agricultural Sciences and Natural Resources | ||
| 3Researcher, Department of Hydrogeology, Helmholtz Center for Environmental Research | ||
| Abstract | ||
| Hyporheic zone is related to the saturated zone beneath the river which has an important role in ecology. In this zone, part of surface water, transfer oxygen and nutrients to the organism and then returns to the surface water after certain amount of time. Hyporheic exchanges between surface flow and flow in porous media can be created due to the different bed forms of river. Riffle-pools are topographical features found in straight, meander and braided rivers. Variation of pressure along these bed forms lead hyporheic exchanges. The precise estimation of hyporheic exchanges and residence time can be useful for rivers restoration projects. So, in this paper, in addition to laboratory investigation of hyporheic exchanges along riffle-pool bed forms, the variation of pressure along bed surface has been simulated numerically by Large Eddy Simulation (LES) model and then a groundwater model and particle tracking method have been applied to simulate the flow within the hyporheic zone. The results show that the interFoam solver with LES model is able to model laboratory conditions accurately. The mean percentage error of water surface profile was 1.8% for present laboratory study, which leads to an accurate estimation of pressure along the bed form and as a result an accurate prediction of hyporheic exchanges. The results of hyporheic characteristics show that as Reynolds number increases, the hyporheic exchanges increase and the residence time decreases. The results also show that the residence time distribution follows generalized extreme value distribution. In this study, on average, 20 percent of surface flow exchange with sub-surface flow. | ||
| Keywords | ||
| Riffle-pool; Hyporheic Exchanges; OpenFOAM; Residence Time | ||
| References | ||
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[1]. Boano F, Harvey JW, Marion A, Packman AI, Revelli R, Ridolfi L, Wörman A. Hyporheic flow and transport processes: Mechanisms, models, and biogeochemical implications. Reviews of Geophysics. 2014: 52(4), 603-679. [2]. Tonina D, Buffington JM. Hyporheic exchange in mountain rivers I: Mechanics and environmental effects. Geography Compass. 2009: 3(3), 1063-1086. [3]. Buffington JM, and Tonina D. Hyporheic exchange in mountain rivers II: Effects of Channel Morphology on Mechanics, Scales, and Rates of Exchange. Geography Compass. 2009: 3(3), 1038-1062. [4]. Stonedahl SH. Investigation of the Effect Multiple Scales of Topography on Hyporheic Exchange. PhD Dissertation, Northwestern University, 2011. [5]. Biddulph M. Hyporheic Zone: In Situ Sampling, Geomorphological Techniques. Chapter 3, Section 11.1, 2015. [6]. Thibodeaux LJ, Boyle JD. Bedform-generated convective transport in bottom sediment. Nature. 1987: 325(6102), 341-343. [7]. Elliott AH, Brooks NH. Transfer of nonsorbing solutes to a streambed with bed forms: Laboratory experiments. Water Resources Research. 1997: 33(1), 137-151. [8]. Packman AI, Salehin M, Zaramella M. Hyporheic exchange with gravel beds: basic hydrodynamic interactions and bedform-induced advective flows. Journal of Hydraulic Engineering. 2004: 130(7), 647-656. [9]. Fox A, Boano F, Arnon S. Impact of losing and gaining streamflow conditions on hyporheic exchange fluxes induced by dune shaped bed forms. Water Resources Research. 2014: 50(3), 1895-1907. [10]. Cardenas MB, Wilson JL. The influence of ambient groundwater discharge on hyporheic zones induced by current-bedform interactions. Journal of Hydrology. 2006: 331, 103–109. [11]. Cardenas MB, Wilson JL. Dunes, turbulent eddies, and interfacial exchange with permeable sediments. Water Resource Research. 2007: 43(8). [12]. Blois G, Best JL, Sambrook Smith GH, Hardy RJ. Effect of bed permeability and hyporheic flow on turbulent flow over bed forms. Geophysical Research Letters. 2014: 41(18), 6435-6442. [13]. Lee DH, Kim YJ, Lee S. Numerical modeling of bed form induced hyporheic exchange. Paddy and Water Environment. 2014: 12(1): 89-97. [14]. Chen X, Cardenas MB, Chen L. Three‐dimensional versus two‐dimensional bed form‐induced hyporheic exchange. Water Resources Research. 2015: 51(4), 2923-2936. [15]. Rodríguez JF, García CM, García MH. Three‐dimensional flow in centered pool‐riffle sequences. Water Resources Research. 2013: 49(1), 202-215. [16]. Tonina D, Buffington JM. Hyporheic exchange in gravel bed rivers with pool‐riffle morphology: Laboratory experiments and three‐dimensional modeling. Water Resources Research. 2007: 43(1). [17]. Zhou T, Endreny T A. Reshaping of the hyporheic zone beneath river restoration structures: Flume and hydrodynamic experiments. Water Resources Research. 2013: 49(8), 5009-5020 [18]. Trauth N, Schmidt C, Maier U, Vieweg M, Fleckenstein JH. Coupled 3‐D stream flow and hyporheic flow model under varying stream and ambient groundwater flow conditions in a pool‐riffle system. Water Resources Research. 2013: 49(9), 5834-5850 [19]. Buffington JM, Montgomery DR. Effects of hydraulic roughness on surface textures of gravel-bed rivers. Water Resources Research. 1999: 35, 3507– 3521. [20]. McSherry RJ, Chua KV, Stoesser T. Large eddy simulation of free-surface flows. Journal of Hydrodynamics. 2017, 29(1): 1-12. [21]. Rodi W, Constantinescu G, Stoesser T. Large eddy simulation in hydraulics. IAHR Monograph, London, UK: CRC Press, Taylor & Francis Group, 2013. [22]. Huang P, May Chui, TFM. Empirical Equations to Predict the Characteristics of Hyporheic Exchange in a Pool Riffle Sequence. Groundwater. 2018: 56(6), 947-958. | ||
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