DESIGNING AND DETAILING OF BUILDING SYSTEMS. MECHANICS IN CIVIL ENGINEERING

DEGREE-BASED VELOCITY DISTRIBUTION INSIDE FLAT AND ROUND TURBULENT FLOWS

Vestnik MGSU 7/2012
  • Skrebkov Gennadiy Petrovich - Chuvash State University named after I.N. Ul’yanov (ChGU) Candidate of Technical Sciences, Associate Professor, Department of Heat and Hydraulic Engineering; +7 (8352) 58-79-26, Chuvash State University named after I.N. Ul’yanov (ChGU), 15 Moskovskiy prospekt, Cheboksary, 428015, Russian Federation; This e-mail address is being protected from spambots. You need JavaScript enabled to view it .
  • Fedorov Nikolay Anfimovich - Chuvash State University named after I.N. Ul’yanov (ChGU) assistant lecturer, Department of Heat and Hydraulic Engineering; +7 (8352) 67-33-26, Chuvash State University named after I.N. Ul’yanov (ChGU), 15 Moskovskiy prospekt, Cheboksary, 428015, Russian Federation; This e-mail address is being protected from spambots. You need JavaScript enabled to view it .

Pages 90 - 95

The authors propose a general method of identification of exponent within the distribution of velocities of round and flat flows. Resulting formulas do not contain any empirical corrections, and they are confirmed by the experimental data.
Resulting degree-based velocity profiles comply with the results of measurements of flat flows, whereas any disagreement between experiment-based points and their analysis-based counterparts do not exceed any acceptable experimental errors.
The practical equivalence of degree-based and logarithmic velocity profiles may serve as a supplementary condition that makes it possible to identify the degree value without the involvement of any empirical corrections.
The degree-based velocity profile of round flows may be calculated according to the expression .\[n=0,9\sqrt{\lambda }\]. or \[n=1,25\sqrt{{{\lambda }_{\text{}}}},\].. the degree-based velocity profile of flat flows is equal to \[n=1,76\sqrt{{{\lambda }_{\text{}}}},\] as both formulas enjoy experimental and theoretical substantiations.

DOI: 10.22227/1997-0935.2012.7.90 - 95

References
  1. Schiller L. Dvizhenie zhidkostey v trubakh [Movement of Fluids in Pipes]. ONTI Publ., Moscow, 1936, p. 230.
  2. Shevelev F.A. Issledovanie osnovnykh gidravlicheskikh zakonomernostey turbulentnogo dvizheniya v trubakh [Investigation of Basic Hydraulic Laws of the Turbulent Flow in Pipes]. Gosstroyizdat Publ., Moscow, 1953, p. 208.
  3. Nunner W. W?rme?bergang und Druckabfall in rauhen R?hren,VDI Forschungsheft, 1956, no. 45.
  4. Al‘tshul‘ A.D. Gidravlicheskie poteri na trenie v truboprovodakh [Hydraulic Friction Loss in Pipes]. Moscow-Leningrad, Gosenergoizdat Publ., 1963, 256 p.
  5. Bryanskaya Yu.V., Markova I.M., Ostyakova A.V. Gidravlika vodnykh i vzvesenesushchikh potokov v zhestkikh i deformiruemykh granitsakh [Hydraulics of Water and Suspension Flows in Rigid and Deformable Boundaries]. Moscow, ASV Publ., 2009, 264 p.
  6. Loytsyanskiy L.G. Mekhanika zhidkosti i gaza [Fluid and Gas Mechanics]. Moscow, Nauka Publ., 1978, 736 p.
  7. Bogomolov A.I., Borovkov V.S. Mayranovskiy T.G. Vysokoskorostnye potoki so svobodnoy poverkhnost’yu [High-speed Flows with Free Surface]. Moscow, Stroyizdat Publ., 1979, p. 344.
  8. Skrebkov G.P. Parashchenko I.E. O velichine postoyannykh logarifmicheskogo profilya skorosti pri dvizhenii potoka mezhdu gladkimi stenkami [The Value of the Permanent Logarithmic Velocity Profile of the Flow between Smooth Walls]. Izvestiya vuzov. Stroitel’stvo i arkhitektura [Bulletin of Institutions of Higher Education. Construction and Architecture]. Novosibirsk, 1983, no. 2, pp. 88—92.
  9. Skrebkov G.P. O gidravlicheskom soprotivlenii rusel ploskomu potoku [About Hydraulic Resistance of Watercourses to Flat Flows]. Proceedings of VNIIG named after B.E. Vedeneeva, 1981, vol.145, pp. 87—92.
  10. Skrebkov G.P., Parashchenko I.E. Issledovanie kinematicheskoy struktury potoka i pristennogo treniya v trapetseidal’nykh kanalakh so stenkami odinakovoy i raznoy sherokhovatosti [Investigation of the Kinematic Structure of the Flow and Wall Friction in the Trapezoidal Channel with the Walls of Identical and Different Roughnesses]. Vodnye resursy [Aquatic Resources]. 1989, no. 2, pp. 91—96.
  11. Laufer J. Investigation of Turbulent Flow in a Two-Dimensional Channel. NACA, Rep. 1053, 1951, pp. 1—33.
  12. Subbotin V.N. Issledovanie osrednennykh gidrodinamicheskikh kharakteristik turbulentnogo potoka v pryamougol’nom kanale [The Study of Averaged Hydrodynamic Characteristics of the Turbulent Flow in a Rectangular Channel]. Obninsk, Institute of Physics and Power Engineering, Preprint, 1973, no. 455.

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Account for the surface tension in hydraulic modeling of the weir with a sharp threshold

Vestnik MGSU 9/2014
  • Medzveliya Manana Levanovna - Moscow State University of Civil Engineering (MGSU) Candidate of Technical Sciences, Associate Professor, Department of Hydraulic Engineering, 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 100-105

In the process of calculating and simulating water discharge in free channels it is necessary to know the flow features in case of small values of Reynolds and Weber numbers. The article considers the influence of viscosity and surface tension on the coefficient of a weir flow with sharp threshold. In the article the technique of carrying out experiments is stated, the equation is presented, which considers the influence of all factors: pressure over a spillway threshold, threshold height over a course bottom, speed of liquid, liquid density, dynamic viscosity, superficial tension, gravity acceleration, unit discharge, the width of the course. The surface tension and liquid density for the applied liquids changed a little. In the rectangular tray (6000x100x200) spillway with a sharp threshold was established. It is shown that weir flow coefficient depends on Reynolds number (in case Re < ~ 2000) and Webers number. A generalized expression for determining weir flow coefficient considering the influence of the forces of viscosity and surface tension is received.

DOI: 10.22227/1997-0935.2014.9.100-105

References
  1. Linford A. The Application of Models to Hydraulic Engineering – Reservoir Spillways. Water and Water Engineering. October, 1965, pp. 351—373.
  2. Engel F., Stainsby W. Weirs for Flow Measurement in Open Channels. Part 2. Water and Water Engineering. 1958, vol. 62, no. 747, pp. 190—197.
  3. Kindsvater C., Carter R. Discharge Characteristics of Rectangular Thin-plate Weirs. Transactions ASCE, 1957, vol. 122, pp. 772—822.
  4. Spronk R. Similitude des ecoulements Sur les deversoirs en mince paroi aux faibles charges. Rev. Univers. mines. 1953, vol. 3, no. 9, pp. 119—127.
  5. Hager W. Ausfluss durch vertikale offnungen. Wasser, Energ. Luft. 1988, vol. 80, no. 3—4, pp. 73—79.
  6. Al’tshul’ A.D., Medzveliya M.L. Ob usloviyakh otryva prilipshey strui na vodoslive s ostrym porogom [On the Conditions of Separating the Stuck Flood on the Weir with a Sharp Threshold]. Izvestiya vuzov: Stroitel’stvo [News of the Institutions of Higher Education]. 1991, no. 11, pp. 73—76.
  7. Medzveliya M.L., Pipiya V.V. Koeffitsient raskhoda vodosliva s shirokim porogom v oblasti malykh naporov [Discharge Ratio of the Broad-crested Weir Flow in the Low Head Area]. Vestnik MGSU [Proceedings of Moscow State University of Civil Engineering]. 2013, no. 4, pp. 167—171.
  8. Medzveliya M.L., Pipiya V.V. Usloviya obrazovaniya svobodnoy strui na vodoslive s ostrym porogom [Conditions of Formation of a Free Flow over a Sharp Crest Weir]. Vestnik MGSU [Proceedings of Moscow State University of Civil Engineering]. 2013, no. 1, pp. 185—189.
  9. Al’tshul’ A.D. Istechenie iz otverstiy zhidkostey s povyshennoy vyazkost’yu [Efflux of Liquids with Elevated Toughness]. Neftyanoe khozyaystvo [Oil Industry]. 1950, no. 2, pp. 55—60.
  10. Jameson A. Flow over Sharp-edged Weirs. Effect of Thickness of Crest . J. Inst. of Civil Engrs. Nov. 1948, vol. 31, no. 1, pp. 36—55. DOI: http://dx.doi.org/10.1680/IJOTI.1948.13377.
  11. D’Alpaos L. Sull’efflusso a stramazzo al di sopra di un bordo in parete sottile perpiccolshi valori del carico. Atti ist. Veneto sci lett. ed arti. Cl, sci mat. e natur. 1976—1977, vol. 135, pp. 169—190.
  12. Shchapov N.M. Gidrometriya gidrotekhnicheskikh sooruzheniy i gidromashin [Hydrometry of Hydraulic Engineering Structures and Hydraulic Units]. Moscow, Leningrad, Gosenergoizdat Publ., 1957, 235 p.
  13. Raju K.G.R., Asawa G.L. Viscosity And Surface Tension Effects On Weir Flow. J. of the Hydraulic Engineering, ASCE. 1977, vol. 103, no. 10, pp. 1227—1231.
  14. Rosanov N., Rosanova N. Some Problems of Modeling Water Outlet Structures with Free — Surface Flow. Proc. 19 IAHR congr. New-Delhi, 1981, vol. 5, pp. 81—91.
  15. Molitor D.A. Hydraulics of Rivers, Weirs and Sluices. 1st ed. New York : John Wiley & Sons; London : Chapman & Hall, Limited. 1908. 178 p.

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DISCHARGE RATIO OF THE BROAD-CRESTED WEIR FLOWIN THE LOW HEAD AREA

Vestnik MGSU 4/2013
  • Medzveliya Manana Levanovna - Moscow State University of Civil Engineering (MGSU) Candidate of Technical Sciences, Associate Professor, Department of Hydraulic Engineering, 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 .
  • Pipiya Valeriy Valerianovich - Breesize Trading Limited Candidate of Technical Sciences, Senior Project Engineer, Breesize Trading Limited, 42 Mosfil’movskaya St., Moscow, 119285, Russian Federation; This e-mail address is being protected from spambots. You need JavaScript enabled to view it .

Pages 167-171

The authors consider the influence of the Reynolds number on the discharge ratio of the broad-crested weir. The authors provide an overview of their experiment in thearticle. They provide the equation that takes account of each factor of influence, including H — pressure over the broad-crested weir, P — weir height above the bottom, v — liquid velocity, ρ — liquid density, μ — dynamic viscosity, g — superficial tension, σ — gravity acceleration, q — per-unit weir flow, B — width of the weir, L — length of the weir. Superficial tension and liquid density values have minor differences for different fluids.A broad-crested weir flow was organized in the rectangular tray (6,000×100×200). The flow had the following dimensions: weir length L = 40 mm, weir height P = 50 mm, weir width B = 100 mm. The findings of the experiment have proven that the increase in the Reynolds number causes the increase in the broad-crested weir flow discharge ratio (at the pre-set relative pressure) and it approaches the constant value at Re ≈ 2000.

DOI: 10.22227/1997-0935.2013.4.167-171

References
  1. Chugaev R.R. Gidravlika [Hydraulics]. Moscow, Energiya Publ., 1975, 671 p.
  2. Linford A. The Application of Models to Hydraulic Engineering-reservoir Spillways. Water and Water engn. October 1965, pp. 411—417.
  3. Al’tshul’ A.D. Istechenie iz otverstiy zhidkostey s povyshennoy vyazkost’yu [Outflows of Hyper-viscosity Liquids through Holes]. Neftyanoe khozyaystvo [Crude Oil Economy]. 1950, no. 2, pp. 55—60.
  4. Zegzhda A.P. Teoriya podobiya i metodika rascheta gidrotekhnicheskikh modeley [Similarity Theory and Methodology of Analysis of Hydraulic Engineering Models]. Moscow, Gosstroyizdat Publ., 1938, 220 p.
  5. Kisilev P.G. Osnovy mekhaniki zhidkosti [Fundamentals of Liquid Mechanics]. Moscow, Energiya Publ., 1980, 337 p.
  6. Medzveliya M.L., Pipiya V.V. Usloviya obrazovaniya svobodnoy strui na vodoslive s ostrym porogom [Conditions of Formation of a Free Flow over a Sharp Crest Weir]. Vestnik MGSU [Proceedings of Moscow State University of Civil Engineering]. 2013, no. 1, pp. 185—189.
  7. Berezinskiy A.R. Propusknaya sposobnost’ vodosliva s shirokim porogom [Throughput of a Broad-crested Weir]. Moscow – Leningrad, Stroyizdat Publ., 1950, 149 p.
  8. Al’tshul’ A.D. Gidravlicheskie soprotivleniya [Hydraulic Resistances]. Moscow, Nedra Publ., 1982, 223 p.

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Hydraulic resistancein channels having rough bottoms

Vestnik MGSU 9/2013
  • Medzveliya Manana Levanovna - Moscow State University of Civil Engineering (MGSU) Candidate of Technical Sciences, Associate Professor, Department of Hydraulic Engineering, 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 .
  • Pipiya Valeriy Valerianovich - Breesize Trading Limited Candidate of Technical Sciences, Senior Project Engineer, Breesize Trading Limited, 42 Mosfil’movskaya St., Moscow, 119285, Russian Federation; This e-mail address is being protected from spambots. You need JavaScript enabled to view it .

Pages 95-100

The authors study the dependence of the hydraulic friction coefficient on the Froude number for open steady uniform flows in channels having a high relative roughness. In the article, the authors provide the equation, which describes the hydraulic resistance in open channels having rough bottoms.Experiments were conducted in the rectangular tray (6,000×100×200 mm). Metal balls having the diameter of 15.1 mm were used to simulate uniform roughness. Aqueous solutions of glycerol were added as operating fluids. Average roughness was identified as k = 0.8d. The range of values of the main factors was as follows: inclination 0.011 —0.06; the Froude number 0.13 — 6.02; relative smoothness 0.3 — 1.36. The authors have proven that the value of the coefficient of hydraulic friction in the zone of the laminar flow is not dependent on the Froude number.The influence of the Froude number on the hydraulic friction is manifested in the areas of the turbulent flow.

DOI: 10.22227/1997-0935.2013.9.95-100

References
  1. Zegzhda A.P. Gidravlicheskie poteri na trenie v kanalakh i truboprovodakh [Hydraulic Friction Losses in Channels and Pipelines]. Moscow, 1967, 282 p.
  2. Reinius R. Steady Uniform Flow in Open Channel. Stokholm, Tekniska Hogskola, no. 5. Handlinger Sweden. 1961, 179, pp. 3—46.
  3. Homma M. Fluid Resistance in Water Flow of High Froud Number. Proc. and Japan Nat. Congr. Appl. Mech. 1952, Sci. Council, Japan, Tokyo, 1953, pp. 251—254.
  4. Kirschmer O. Reibungsverluste in Rohren und Kanalen. Gas- und Wasserfach. 1966, vol. 107, no. 50, pp. 1405—1416.
  5. Rouse H., Koloseus. The Role of Froude Number in Open Channel Resistance. Hydr. Research. IANR. Holland. 1963, vol.1, no. 1.
  6. Rouse H. Critical Analysis of Open Channel Resistance. J. Hydr. Div. Proc. ASCE. 1965, no. 4, 91, part 1, pp. 1—25.
  7. Al'tshul' A.D. Gidravlicheskie soprotivleniya [Hydraulic Resistances]. Moscow, Nedra Publ., 1982, 223 p.
  8. Al'tshul' A.D., Lyapin V.Yu., Al'kheder B. O vliyanii formy secheniya rusla na gidrodinamicheskie kharakteristiki turbulentnykh potokov [On the Influence of the Shape of the Channel Section on Hydro-dynamic Characteristics of Turbulent Flows]. Izvestiya vuzov. Energetika [News of Institutions of Higher Education. Power Engineering]. 1992, no. 4, pp. 91—94.
  9. Medzveliya M.L., Pipiya V.V. Faktory, vliyayushchie na koeffitsient gidravlicheskogo treniya ravnomernykh otkrytykh potokov [Factors of Influence on the Coefficient of Hydraulic Friction for Open Uniform Flows]. Vestnik MGSU [Proceedings of Moscow State University of Civil Engineering]. 2011, no. 8, pp. 398—402.
  10. Al'tshul' A.D. Gazogidravlicheskaya analogiya N.E. Zhukovskogo i ee znachenie dlya gidrotekhniki [N.E. Zhukovskiy’s Gas-hydraulic Analogy and Its Significance for Hydraulic Engineering]. Gidrotekhnicheskoe stroitel'stvo [Hydraulic Engineering Construction]. 1948, no. 8, pp. 14—19.
  11. Poltavtsev V.I., Efremov V.I. Ob osobennostyakh gidravlicheskogo soprotivleniya otkrytykh potokov pri bol'shoy sherokhovatosti rusla [On Features of Hydraulic Resistance of Open Flows in Case of High Roughness of the Channel]. Trudy LGMI [Works of the Leningrad Institute of Hydrometeorology]. 1967, no. 25, pp. 5—12.

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The coefficientof hydraulic friction of laminar open flows in smooth channels

Vestnik MGSU 5/2015
  • Medzveliya Manana Levanovna - Moscow State University of Civil Engineering (MGSU) Candidate of Technical Sci- ences, Associate Professor, Department of Hydraulics, 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 .
  • Borovkov Valeriy Stepanovich - Moscow State University of Civil Engineering (MGSU) Doctor of Technical Sciences, Professor, Department of Hydraulics, Moscow State University of Civil Engineering (MGSU), 26 Yaroslavskoe shosse, Moscow, 129337, Russian Federation; mgsu-hydraulic@ yandex.ru; This e-mail address is being protected from spambots. You need JavaScript enabled to view it .

Pages 86-92

The article examines the dependence of the hydraulic friction coefficient of open laminar uniform streams on the relative width of channels with smooth bottom. The article presents the functional dependence that describes the hydraulic resistance in open channels with smooth bottoms.The experiments were carried out in a rectangular tray (6000×100×200). Aqueous solutions of glycerol were used as working fluids. The superficial tension and liquid density for the used liquids changed a little. The article declares that the coefficient of hydraulic friction λ in the zone of the laminar flow depends on the relative width of the channels with smooth bottom. In the article it is also shown that the Charny formula satisfactorily agrees with the theoretical formula and with the experimental data.

DOI: 10.22227/1997-0935.2015.5.86-92

References
  1. Orellana J., Chang P. Limitations of Chézy’s Equation in River Hydraulics as It Relates to Channel Geometry and Flow Properties. Proceedings, Annual Conference — Canadian Society for Civil Engineering. 2012, vol. 1, pp. 318—324.
  2. Dolgopolova E.N. Energy Losses and Hydraulic Friction of Open and Ice-Covered River Flow. Power Technology and Engineering. 2011, vol. 45, no. 1, pp. 17—24. DOI: http://dx.doi.org.10.1007/s10749-011-0218-4.
  3. Di Cristo C., Iervolino M., Vacca A., Zanuttigh B. Influence of Relative Roughness and Reynolds Number on the Roll-Waves Spatial Evolution. Journal of Hydraulic Engineering. 2010, vol. 136, no. 1, pp. 24—33. DOI: http://dx.doi.org/10.1061/(ASCE)HY.1943-7900.0000139.
  4. Zhang K., Wang G., Sun X., Yang F., Lü H. Experiment on Hydraulic Characteristics of Shallow Open Channel Flow on Slope. Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering. 2014, vol. 30, no. 15, pp. 182—189. DOI: http://dx.doi.org/10.3969/j.issn.1002-6819.2014.15.024.
  5. Roche N., Daïan J.-F., Lawrence D.S.L. Hydraulic Modeling of Runoff over a Rough Surface under Partial Inundation. Water Resources Research. 2007, vol. 43, no. 8. Available at: http://onlinelibrary.wiley.com/doi/10.1029/2006WR005484/full#publication-history/. Date of access: 20.02.2015. DOI: http://dx.doi.org/10.1029/2006wr005484.
  6. Al’tshul’ A.D., Pulyaevskiy A.M. O gidravlicheskikh soprotivleniyakh v ruslakh s usilennoy sherokhovatost’yu [On Hydraulic Resistance in Channels with Increased Unevenness]. Gidrotekhnicheskoe stroitel’stvo [Hydraulic Engineering]. 1974, no. 7, pp. 27—29. (In Russian)
  7. Reinius R. Steady Uniform Flow in Open Channel. Division of Hydraulics, Royal Institute of Technology, Stockholm, Sweden, 1961, bulletin 60, 46 p.
  8. Tracy H.J., Lester C.M. Resistance Coefficient and Velocity Distribution in Smooth Rectangular Channel. Geological Survey Water-Supply Paper 1592-A. Washington, US Government printing office, 1961, 18 p.
  9. Al’tshul’ A.D. Gazogidravlicheskaya analogiya N.E. Zhukovskogo i ee znachenie dlya gidrotekhniki [Hydraulic Analogy of N.E. Zhukovsky and its Role in Hydraulic Engineering]. Gidrotekhnicheskoe stroitel’stvo [Hydraulic Engineering]. 1948, no. 8, pp. 14—19. (In Russian)
  10. Medzveliya M.L., Pipiya V.V. Faktory, vliyayushchie na koeffitsient gidravlicheskogo treniya ravnomernykh otkrytykh potokov [The Factors Influencing the Pipe Friction Number of Uniform Open Channels]. Vestnik MGSU [Proceedings of Moscow State University of Civil Engineering]. 2011, no. 8, pp. 398—402. (In Russian)
  11. Al’tshul’ A.D., Lyapin V.Yu., Medzveliya M.L. Vliyanie chisla Fruda na koeffitsient gidravlicheskogo treniya ravnomernykh otkrytykh potokov [The Influence of Froude Number on the Pipe Friction Number of Uniform Open Channels]. Izvestiya vysshikh uchebnykh zavedeniy. Stroitel’stvo [News of the Institutions of Higher Education. Construction]. 1991, no. 11, pp. 102—105. (In Russian)
  12. Medzveliya M.L., Pipiya V.V. Gidravlicheskoe soprotivlenie lotkov s sherokhovatym dnom [Hydraulic Resistance in Channels Having Rough Bottoms]. Vestnik MGSU [Proceedings of Moscow State University of Civil Engineering]. 2013, no. 9, pp. 95—100. (In Russian)
  13. Straub L.G., Silberman E., Nelson H.C. Some Observations on Open Channel Flow at Small Reynolds Numbers. J. eng. mech. div ASCE. 1956, vol. 82, no. 3, pp. 1—28.
  14. Al’tshul’ A.D., Lyapin V.Yu., Al Heder B. O vliyanii formy secheniya rusla na gidrodinamicheskie kharakteristiki turbulentnykh potokov [On the Influence of the Shape of the Channel Section on Hydro-dynamic Characteristics of Turbulent Flows]. Izvestiya vuzov. Energetika [News of Institutions of Higher Education. Power Engineering]. 1992, no. 4, pp. 91—94. (In Russian)
  15. Kruger F. Der Einfluss der Querschnittsform auf den Fliesswiderstand offener Rechteckgerinne. Wasserwirtschaft-Wassertechnik. 1989, Jg. 39, Nr. 1, S. 19—20.
  16. Rabinovich E.Z. Gidravlika [Hydraulics]. 2nd edition. Moscow, Nedra Publ., 1977, 266 p. (In Russian)

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