DESIGNING AND DETAILING OF BUILDING SYSTEMS. MECHANICS IN CIVIL ENGINEERING

Intensity and probability-related properties of turbulence of steady river flows

Vestnik MGSU 9/2012
  • Volynov Mikhail Anatolevich - All-Russian Research Institute of Hydraulic Engineering and Land Reclamation named after A.N. Kostyakov (VNIIGIM) Candidate of Technical Sciences, Associate Professor, Head of Department of Water Resources Management, All-Russian Research Institute of Hydraulic Engineering and Land Reclamation named after A.N. Kostyakov (VNIIGIM), 44 Bolshaya Akademicheskaya st., Moscow, 127550, Russian Federation; This e-mail address is being protected from spambots. You need JavaScript enabled to view it .
  • Pisarev Denis Vladlenovich - Moscow State University of Civil Engineering (MGSU) Assistant Lecturer, Department of Hydraulics 8 (499) 261-39-12, Moscow State University of Civil Engineering (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation; This e-mail address is being protected from spambots. You need JavaScript enabled to view it .

Pages 89 - 94

The article represents an overview of the field studies of the intensity and distribution of probability
of longitudinal turbulent velocity fluctuations in river flows with different sizes of beds and
hydrological characteristics. The authors demonstrate that the normalizing transformation of velocity
fluctuations performed by the local friction velocity makes it possible to get the changes of velocity
fluctuations deep inside the flow close to universal.
The authors have also identified that the intensity of turbulent velocity fluctuations exceeds
the friction velocity 2.5-3-fold in the area close to the river bottom, while their intensities demonstrate
their gradual decline closer to the surface of the flow. The authors have derived an approximation
formula, describing the change of the intensity of longitudinal velocity fluctuations
deep inside river flows.
Probability distributions of longitudinal velocity fluctuations were compared to those based on
the law of Gauss. It is proven that they have a kurtosis of a frequency curve as well as an asymmetry
in comparison with the distribution of Gauss, which are most vivid in the area close to the bottom of the flow. Due to the fact that the coefficient of asymmetry includes a third degree of velocity fluctuations,
and a kurtosis of the frequency curve, experimental identification of these characteristics
is problematic for the reason of their instability. The new information concerning the intensity and
probability properties of the river flow turbulence can be used in projecting the mixture formation and
mass exchange processes ongoing inside river flows.

DOI: 10.22227/1997-0935.2012.9.89 - 94

References
  1. Kukolevskiy G.A. Gidravliko-veroyatnostnye kharakteristiki ruslovykh protsessov [Hydraulic and Probablistic Characteristics of River Bed Processes]. Works of the 5th National Hydrology Congress. Leningrad, Gidrometeoizdat Publ., 1988, vol. 10, Book 1, pp. 98—103.
  2. Harvey A.M. Some Aspects of the Relation between Channel Characteristics and Riffle Spacing in Meandering Channels. Wn. J. Sci., 1975, vol. 275, pp. 470—478.
  3. Bågin Z.B. Relationship between Flow Shear Stress and Stream Patterns. J. Hydrol. 1981, no. 3-4, pp. 307—319.
  4. Bryanskaya Yu.V., Baykov V.N., Volynov M.A. Raspredelenie skorostey i gidravlicheskoe soprotivlenie pri techenii v trubakh, kanalakh i rechnykh ruslakh [Velocity Distribution and Hydraulic Resistance of Flows in Pipes, Channels and River Beds]. Gidrotekhnicheskoe stroitel’stvo [Hydraulic Engineering]. 2011, no. 3, pp. 37—39.
  5. Davies T.R., Sutherland A.J. Resistance to Flow Past Deformable Boundaries. Earth Surf. Processes, 1980, vol. S, pp. 175—179.
  6. Kont-Bello Zh. Turbulentnoe techenie v kanale s parallel’nymi stenkami [Turbulent Flow in the Parallel Wall Channel]. Moscow, Mir Publ., 1968, 325 p.
  7. Hanjalic K., Launder B. Fully Developed Asymmetric Flow in Plane Channel. J. Fluid Mech., vol. 51, part 2, 1972.
  8. Berkovich K.M., Chalov R.S. Ruslovoy rezhim rek i printsipy ego regulirovaniya pri razvitii volnovogo transporta [Regimen of River Beds and Principles of Its Regulation with Reference to Water Transport Development]. Geografi ya i prirodnye resursy [Geography and Natural Resources]. 1993, no. 1, pp. 10—17.

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