Reynolds Number

Reynolds number (Re) is an experimental number used to predict the flow velocity in fluid flow at which turbulence will occur. It is a non-dimensional velocity can be defined as the ratio of a fluid’s inertia force to the viscous forces.

Reynolds number formula

ρ = mass density of the fluid,
v = Velocity of the fluid,
L = The characteristic linear dimension, (traveled length of the fluid; hydraulic diameter when dealing with river systems),
μ = Dynamic viscosity of the fluid,
v = Kinematic viscosity of the fluid.

Reynolds number is used to determine whether a flow of a fluid will be laminar, turbulent or transitional flow. Below a critical Reynolds number, flow will be laminar. Above a critical Reynolds number, flow will be turbulent.

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All Comments

  • Good and helpful website

    lekan Apr 19, 2016 11:24 pm Reply
  • NICE

    KRISH Aug 23, 2016 6:22 pm Reply
  • Very precise.

    Kiran kumar Oct 6, 2017 11:40 am Reply

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