THE SUMMARIZED FORMULA FOR VELOCITY OF TURBULENT AND LAMINAR FLOWS IN PIPES
https://doi.org/10.30724/1998-9903-2018-20-7-8-136-146
Abstract
On the basis of the solution of the equation of the movement (in conception of «vortex backfill”) offered earlier, the generalized formula for a profile of speed of a turbulent and laminar current in pipes is received. The formula has binomial power shape. The received solution allows to consider speed of a turbulent kernel of a stream, or, more precisely, averaged on time value of axial component of this speed, as the sum of three items - carrying, parabolic and power but not parabolic. It is shown that the profile of turbulent speed of the basic part of a stream is described by the parabolic component. Transformation of the equation of movement in which solutions both laminar, and turbulent profiles of speeds (in the basic part of a stream) are direct lines (or very close to them) is offered. Some features of turbulent flow, similar to currents in a granular layer are noted.
Keywords
turbulence,
pipes,
an equation of motion,
interior resistance,
a profile of velocities,
the power formula
Supporting agencies: Russian fund of basic researches (RFFI, the project №18-08-00051а)
About the Authors
L. E. Melamed
Closed joint-stock company "Intelligence", Moscow
Russian Federation
Russian Federation
Lev Emmanuilovich Melamed – Dr. Sci. (Techn.), chief scientist of closed joint-stock company “Intelligence”, 117246 Moscow
G. A. Filippov
Department of power, mechanical engineering, mechanics and control processes of Russian Academy of Sciences, Moscow
Russian Federation
Russian Federation
Gennady Alekseevich Filippov – Dr. Sci. (Techn.), professor, member of Russian Academy of Sciences, Department of power, mechanical engineering, mechanics and control processes, 119991 Moscow
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Review
For citations:
Melamed L.E., Filippov G.A. THE SUMMARIZED FORMULA FOR VELOCITY OF TURBULENT AND LAMINAR FLOWS IN PIPES. Power engineering: research, equipment, technology. 2018;20(7-8):136-146. (In Russ.) https://doi.org/10.30724/1998-9903-2018-20-7-8-136-146
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