What is laminar: Definition and 67 Discussions

In fluid dynamics, laminar flow is characterized by fluid particles following smooth paths in layers, with each layer moving smoothly past the adjacent layers with little or no mixing. At low velocities, the fluid tends to flow without lateral mixing, and adjacent layers slide past one another like playing cards. There are no cross-currents perpendicular to the direction of flow, nor eddies or swirls of fluids. In laminar flow, the motion of the particles of the fluid is very orderly with particles close to a solid surface moving in straight lines parallel to that surface.
Laminar flow is a flow regime characterized by high momentum diffusion and low momentum convection.
When a fluid is flowing through a closed channel such as a pipe or between two flat plates, either of two types of flow may occur depending on the velocity and viscosity of the fluid: laminar flow or turbulent flow. Laminar flow occurs at lower velocities, below a threshold at which the flow becomes turbulent. The threshold velocity is determined by a dimensionless parameter characterizing the flow called the Reynolds number, which also depends on the viscosity and density of the fluid and dimensions of the channel. Turbulent flow is a less orderly flow regime that is characterized by eddies or small packets of fluid particles, which result in lateral mixing. In non-scientific terms, laminar flow is smooth, while turbulent flow is rough.

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  1. H

    B Some Questions About Drag (for ships in water and airplanes in air)

    I'm interested in the very basics of drag, both for ships in water and airplanes in air. Here's what I have so far : Flow of the medium can be laminar or turbulent. As the relative speed of the vessel increases, the more likely the flow is to be turbulent. Laminar drag increases linearly...
  2. S

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  3. FebinThomas

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  4. L

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  5. R

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  6. G

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  7. G

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  8. A

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  9. H

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  10. M

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  11. T

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  12. M

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  13. S

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  14. jdawg

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  15. A

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  16. W

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  17. F

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  18. H

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  19. M

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  20. E

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    < Mentor Note -- please remember to use the Homework Help Template when posting schoolwork questions > Consider the fully developed laminar flow due to gravity of water in a vertical circular tube. Assume atmospheric pressure at inlet and outlet. Show that the relationship between diameter and...
  21. Dong Aleta

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  22. V

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  23. R

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  24. throneoo

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  25. arthurchen

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  26. D

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  27. R

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  28. J

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  29. C

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  30. N

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  31. J

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  32. A

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  33. P

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  34. S

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  35. B

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  36. K

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  37. P

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  38. M

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  39. E

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  40. A

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  41. S

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  42. F

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  43. F

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  44. W

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  45. R

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  46. T

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  47. V

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  48. S

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