What is Turbulent flow: Definition and 51 Discussions

In fluid dynamics, turbulence or turbulent flow is fluid motion characterized by chaotic changes in pressure and flow velocity. It is in contrast to a laminar flow, which occurs when a fluid flows in parallel layers, with no disruption between those layers.Turbulence is commonly observed in everyday phenomena such as surf, fast flowing rivers, billowing storm clouds, or smoke from a chimney, and most fluid flows occurring in nature or created in engineering applications are turbulent. Turbulence is caused by excessive kinetic energy in parts of a fluid flow, which overcomes the damping effect of the fluid's viscosity. For this reason turbulence is commonly realized in low viscosity fluids. In general terms, in turbulent flow, unsteady vortices appear of many sizes which interact with each other, consequently drag due to friction effects increases. This increases the energy needed to pump fluid through a pipe.
The onset of turbulence can be predicted by the dimensionless Reynolds number, the ratio of kinetic energy to viscous damping in a fluid flow. However, turbulence has long resisted detailed physical analysis, and the interactions within turbulence create a very complex phenomenon. Richard Feynman has described turbulence as the most important unsolved problem in classical physics.

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  1. Y

    I Force applied on sphere by turbulent flow

    Hello everybody, I am thinking of the following problem: A sphere a radius r is in a much larger container of radius R. In this container, a fluid continuously flows with turbulent conditions from bottom to top. I would like to approximate the force pushing the sphere up. Some calculations I...
  2. R

    Programs Universities for Research in Dynamical Systems of Fluids

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  3. axelb

    I How is the Reynolds number derived (is my derivation wrong)?

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  4. T

    What is the better way to create less turbulent flow with a blower?

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  5. FebinThomas

    I Regarding when to consider both laminar and turbulent flow

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  6. G

    I Geometric Interpretation of Turbulence

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  7. M

    Finding height of buffer regions and viscous sublayer turbulent flow

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  8. M

    I What is the purpose of the Prandtl Mixing Length for turbulent flow?

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  9. A

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  10. E

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  11. T

    I Can Turbulent Flow Be Predicted?

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  12. Domenico94

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  13. C

    Would there be turbulence around objects w/o boundary layers

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  14. A

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  15. jamalkoiyess

    A Modeling and simulating a 2D Turbulent flow

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  16. H

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  17. S

    A Can the wave function show turbulence?

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  18. F

    Nusselt number for a developing turbulent flow in the entrance region

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  19. Kevin Halagan

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  20. R

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  21. Jehannum

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  22. W

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  23. G

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  24. N

    Is Turbulence at Point A Isotropic? Calculation Help

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  25. R

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  26. S

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  27. J

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  28. S

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  29. B

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  30. K

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  31. P

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  32. H

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  33. T

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  34. S

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  35. S

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  36. S

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  37. 1

    Fluid Mechanics - Turbulent flow velocity profile

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  38. C

    Drag (Turbulent Flow) Question

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  39. D

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  40. R

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  41. M

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  42. 1

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  43. P

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  44. wolram

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  45. G

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  46. G

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  47. T

    Taphonomy and turbulent flow dynamics

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  48. wolram

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  49. S

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  50. S

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