IEVref:113-03-36ID:
Language:enStatus: Standard
Term: Reynolds number
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Symbol: Re
Definition: quantity of dimension 1 characterizing the flow of a fluid in a given configuration characterized by a specified length l, defined by Re= ρvl η = vl ν MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqk0di9Wr=fpeei0di9v8qiW7rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaeaaciWacmGadaGadeaabaGaaqaaaOqaaiaadkfacaaMb8Uaam yzaiaaykW7cqGH9aqpcaaMc8+aaSaaaeaacqaHbpGCruGqV92AGeKB 0LwC1fgaiuGacaWF2bGaamiBaaqaaiabeE7aObaacaaMc8Uaeyypa0 JaaGPaVpaalaaabaGaa8NDaiaadYgaaeaacqaH9oGBaaaaaa@5207@ , where the fluid is described by its mass density ρ, speed v, dynamic viscosity η, and kinematic viscosity ν

NOTE 1 The Reynolds number characterizes the relative importance of inertia and viscosity in a fluid flow.

NOTE 2 When the Reynolds number is less than a critical value Recrit, laminar flow is stable. For higher values of Re, laminar flow becomes unstable. The critical value depends on the configuration.

NOTE 3 In case of a fluid flowing through a circular tube with diameter d, the specified length is l = d, and the critical value of the Reynolds number is Recrit ≈ 2 300.


Publication date:2011-04
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Internal notes:2017-06-02: Cleanup - Remove Attached Image 113-03-36en.gif
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