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In the context of particulate motion the Péclet number has also been called Brenner number, with symbol Br, in honour of Howard Brenner. [ 2 ] The Péclet number also finds applications beyond transport phenomena, as a general measure for the relative importance of the random fluctuations and of the systematic average behavior in mesoscopic ...
Dimensionless numbers (or characteristic numbers) have an important role in analyzing the behavior of fluids and their flow as well as in other transport phenomena. [1] They include the Reynolds and the Mach numbers, which describe as ratios the relative magnitude of fluid and physical system characteristics, such as density, viscosity, speed of sound, and flow speed.
Small values of the Prandtl number, Pr ≪ 1, means the thermal diffusivity dominates. Whereas with large values, Pr ≫ 1, the momentum diffusivity dominates the behavior. For example, the listed value for liquid mercury indicates that the heat conduction is more significant compared to convection, so thermal diffusivity is dominant. However ...
Fig 2: The grid used for discretisation in Upwind Difference Scheme for positive Peclet number (Pe>0) Fig 3: The grid used for discretisation in Upwind Difference Scheme for negative Peclet number (Pe < 0) By putting these values in equation and rearranging we get the following result,
[1] [2] [3] The effect is named after the British fluid dynamicist G. I. Taylor, who described the shear-induced dispersion for large Peclet numbers. The analysis was later generalized by Rutherford Aris for arbitrary values of the Peclet number. The dispersion process is sometimes also referred to as the Taylor-Aris dispersion.
The turbulent Schmidt number is commonly used in turbulence research and is defined as: [3] = where: is the eddy viscosity in units of (m 2 /s); is the eddy diffusivity (m 2 /s).; The turbulent Schmidt number describes the ratio between the rates of turbulent transport of momentum and the turbulent transport of mass (or any passive scalar).
It requires that transportiveness changes according to magnitude of peclet number i.e. when pe is zero is spread in all directions equally and as Pe increases (convection > diffusion) at a point largely depends on upstream value and less on downstream value. But central differencing scheme does not possess transportiveness at higher pe since Φ ...
Is it worth saying that values of the Peclet number are typically very large in most engineering applications? 128.12.20.32 21:49, 21 February 2006 (UTC) []. Absolutely. I think that is a useful piece of information and I have added it to the article.