Experimental study of two phase Air-water Flow Parameters in Hydraulic Jumps with vegetated Rough Bed

Document Type : Research Article

Authors

1 Faculty of Water and Environmental Engineering,, Department of Hydraulic Structures, Shahid Chamran University of Ahvaz.

2 Associate Professor. Faculty of Water and Environmental Engineering, Department of Hydraulic Structures, Shahid Chamran University of Ahvaz

3 Professor. Faculty of Water and Environmental Engineering, Department of Hydraulic Structures, Shahid Chamran University of Ahvaz

Abstract

Hydraulic jumping is a complex three-dimensional phenomenon which is frequently observed in open channel flow such as rivers. The hydraulic resistance of vegetation plays a major role in the hydrodynamics of rivers with extensive natural floodplains. Vegetation penetrates the flow field and creates resistant force and, consequently, energy dissipation. In this study, the effect of vegetation density and height on flow in a hydraulic jump and parameters related to two phase Air-water flow are examined using cylindrical elements made of galvanized iron with a homogeneous diameter of 7 mm as vegetation. Thus, neither the effects of plant diversity nor flexibility have been considered. For this purpose, four forms of rough bed were used in two modes of staggered and collocated grid roughness with two heights of 1.5 and 3 cm, and the results were compared with data on smooth bed as a reference. Experiments were conducted in a horizontal rectangular flume with a width of 30 cm, in the range of upstream Froude numbers between 1.5 Fr1 5.5. Air-water flow measurements were conducted with a dual-tip conductivity probe, which was designed, developed and calibrated in this research. The results of this study showed that the presence of vegetation increases aeration by increasing the void fraction in a jump roller. And on the other hand, increasing the resistant force and shear stress in the bed reduces conjugate depths and roller length. This increase and decrease depends on the upstream Froude numbers, height and density of vegetation.

Keywords

References

  • Bélanger J. Notes sur l'Hydraulique. Ecole Royale des Ponts et Chaussées, Paris, France, session. 1841;1842:223.
  • Cummings PD, Chanson H. Air Entrainment in the Developing Flow Region of Plunging Jets—Part 1: Theoretical Development. Journal of Fluids Engineering‌ـ transactions of The Asme. 1997;119:597‌ـ
  • Chanson H, Brattberg T. Air Entrainment by Two‌ـ Dimensional Plunging Jets: the Impingement Region and the Very‌ـ Near Flow Field. Proceedings of 1998 ASME Fluids Engineering Conference. 1998:8.
  • Chanson H. Advective diffusion of air bubbles in hydraulic jumps with large Froude numbers: an experimental study. 2009a.
  • Wang H. Turbulence and air entrainment in hydraulic jumps. 2014.
  • Cain P, Wood IR. Measurements of self‌ـ aerated flow on a spillway. Journal of the Hydraulics Division. 1981;107(11):1425‌ـ
  • Hager W, Sinniger R. Flow characteristics of the hydraulic jump in a stilling basin with an abrupt bottom rise. Journal of Hydraulic Research. 1985;23(2):101‌ـ
  • Rajaratnam N. Hydraulic jumps. Advances in hydroscience. 4: Elsevier; 1967. p. 197‌ـ
  • Ead S, Rajaratnam N. Hydraulic jumps on corrugated beds. Journal of Hydraulic Engineering. 2002;128(7):656‌ـ
  • Hughes WC, Flack JE. Hydraulic jump properties over a rough bed. Journal of Hydraulic engineering. 1984;110(12):1755‌ـ
  • Abel R, Resch FJ. A method for the analysis of hot‌ـ film anemometer signals in two‌ـ phase flows. International Journal of Multiphase Flow. 1978;4(5):523‌ـ
  • Resch FJ, Leutheusser HJ, Alemu S. Bubbly two‌ـ phase flow in hydraulic jump. Journal of the Hydraulics Division. 1974;100(1):137‌ـ
  • Lee B. Review of the present status of optical fiber sensors. Optical fiber technology. 2003;9(2):57‌ـ
  • Chanson H. Phase‌ـ detection measurements in free‌ـ surface turbulent shear flows. Journal of Geophysics and Engineering. 2016;13(2):S74‌ـ
  • Neal LG, Bankoff S. A high resolution resistivity probe for determination of local void properties in ga“ liquid flow. Aiche Journal. 1963;9:490‌ـ
  • Felder S, Chanson H. Air–water flow patterns of hydraulic jumps on uniform beds macroroughness. Journal of Hydraulic Engineering. 2018;144(3):04017068.
  • Pagliara S, Carnacina I, Roshni T. Air‐water flows in the presence of staggered and row boulders under macroroughness conditions. Water Resources Research. 2010;46(8).
  • Pagliara S, Roshni T, Carnacina I. Turbulence, aeration and bubble features of air‌ـ water flows in macro‌ـ and intermediate roughness conditions. Water Science and Engineering. 2011;4(2):170‌ـ
  • Pagliara S, Palermo M. Hydraulic jumps on rough and smooth beds: aggregate approach for horizontal and adverse‌ـ sloped beds. Journal of Hydraulic Research. 2015;53(2):243‌ـ
  • Felder S, Chanson H. An experimental study of air‌ـ water flows in hydraulic jumps with channel bed roughness. 2016.
  • Chanson H, Carosi G. Advanced post‌ـ processing and correlation analyses in high‌ـ velocity air–water flows. Environmental Fluid Mechanics. 2007a;7(6):495‌ـ
  • Chanson H. Momentum considerations in hydraulic jumps and bores. Journal of Irrigation and Drainage Engineering. 2012;138(4):382‌ـ
  • Kucukali S, Chanson H. Turbulence measurements in the bubbly flow region of hydraulic jumps. Experimental Thermal and Fluid Science. 2008;33(1):41‌ـ
  • Bahmanpouri F. Experimental study of air entrainment in hydraulic jump on pebbled rough bed. PhD thesis: Civil, Architectural and Environmental Engineering Department, The University of Napoli Federico II; 2019.
  • Chachereau Y, Chanson H. Free‌ـ surface fluctuations and turbulence in hydraulic jumps. Experimental Thermal and Fluid Science. 2011b;35(6):896‌ـ
  • Murzyn F, Mouazé D, Chaplin J. Air–water interface dynamic and free surface features in hydraulic jumps. Journal of Hydraulic Research. 2007;45(5):679‌ـ
  • Carollo FG, Ferro V, Pampalone V. Hydraulic jumps on rough beds. Journal of Hydraulic Engineering. 2007;133(9):989‌ـ
  • Murzyn F, Chanson H. Experimental investigation of bubbly flow and turbulence in hydraulic jumps. Environmental Fluid Mechanics. 2009;9(2):143‌ـ
  • Chanson H. Convective transport of air bubbles in strong hydraulic jumps. International Journal of Multiphase Flow. 2010;36(10):798‌ـ
  • Crank J. The mathematics of diffusion: Oxford university press; 1979.
  • Chanson H. Air entrainment in two‌ـ dimensional turbulent shear flows with partially developed inflow conditions. International Journal of Multiphase Flow. 1995;21(6):1107‌ـ
  • Chanson H. Air bubble entrainment in free‌ـ surface turbulent shear flows: Elsevier; 1997a.
  • Chanson H. Study of air entrainment and aeration devices. Journal of Hydraulic research. 1989;27(3):301‌ـ
  • Brattberg T, Chanson H, Toombes L. Experimental investigations of free‌ـ surface aeration in the developing flow of two‌ـ dimensional water jets. 1998.
  • Murzyn F, Mouazé D, Chaplin J. Optical fibre probe measurements of bubbly flow in hydraulic jumps. International Journal of Multiphase Flow. 2005;31(1):141‌ـ
  • Chachereau Y, Chanson H. Bubbly flow measurements in hydraulic jumps with small inflow Froude numbers. International Journal of Multiphase Flow. 2011;37(6):555‌ـ
Iranian journal of Ecohydrology
Volume 8, Issue 3
October 2021
Pages 763-775

Files

History

  • Receive Date: 22 May 2021
  • Revise Date: 28 August 2021
  • Accept Date: 16 August 2021
  • First Publish Date: 23 September 2021
  • Publish Date: 23 September 2021

Share

How to cite

Statistics