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The Péclet number (Pe) is a class of dimensionless numbers relevant in the study of transport phenomena in a continuum. It is named after the French physicist Jean Claude Eugène Péclet . It is defined to be the ratio of the rate of advection of a physical quantity by the flow to the rate of diffusion of the same quantity driven by an appropriate gradient.

It is named after J. Péclet. References. J. M. Kay, R. M. Nedderman, "An Introduction to Fluid Mechanics and Heat Transfer", 3rd ed., Cambridge University Press (1974) ISBN 0-521-20533-6 Zbl The Péclet number (Pe) is a class of dimensionless numbers relevant in the study of transport phenomena in a continuum. It is named after the French physicist Jean Claude Eugène Péclet. It is defined to be the ratio of the rate of advection of a physical quantity by the flow to the rate of diffusion of the same quantity driven by an appropriate gradient. Peclet number is the ratio of the heat transferred by convection to the heat transferred by conduction.

Peclet number

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A criterion based on a Péclet number is often used to decide whether transport by advection should be considered. A Péclet number is a dimensionless number than can relate the effectiveness of mass transport by advection to the effectiveness of mass transport by either dispersion or diffusion (Fetter 1999). Usually, diffusion is considered as the dominant The Peclet number (Pe), a dimensionless number that characterizes the relative importance of diffusion to convection, is often used in the context of mixing of continuously flowing streams. The Peclet number is given by . l. 2. D. t Pe = = = diff.

17 Nov 2012 File:Diagram showing the variation of any property (Ø) along the length (L) at different Peclet numbers (Pe)..png · Captions · SummaryEdit 

It is named after the French physicist Jean Claude Eugène Péclet. It is defined to be the ratio of the rate of advection of a physical quantity by the flow to the rate of diffusion of the same quantity driven by an appropriate gradient. A criterion based on a Péclet number is often used to decide whether transport by advection should be considered. A Péclet number is a dimensionless number than can relate the effectiveness of mass transport by advection to the effectiveness of mass transport by either dispersion or diffusion (Fetter 1999).

Peclet number

Does the finite element method also have a numerical stability criteria with respect to the Peclet number? If so what are the standard techniques to maintain  

The Péclet number is defined as the ratio of the rate of advection of a physical quantity by the flow to the rate of diffusion (matter or heat) of the same quantity driven by an appropriate gradient. Therefore we must distinguish between Peclet number for mass transfer and heat transfer. Peclet number, Pe, is a dimensionless group representing the ratio of heat transfer by motion of a fluid to heat transfer by thermal conduction. The Péclet number characterizes the relation between the convective and molecular heat-transport processes in a flow of liquid: $$ \mathrm{Pe} = \frac{v l}{\alpha} = \frac{C_p \rho v}{\lambda/l} $$ where $l$ is the characteristic linear scale of the heat-transfer surface, $v$ is the velocity of the liquid relative to that surface, $\alpha$ is thermal diffusion coefficient, $C_p$ is the heat capacity at constant pressure, $\rho$ is the density, and $\lambda$ is the thermal conductivity The Péclet number (Pe) is a dimensionless number that represents the ratio of the convection rate over the diffusion rate in the a convection-diffusion transport system. [1][2] [math]\displaystyle{ Pe = \frac{(Convection \, rate)}{(Diffusion \, rate)} = \frac {UL}{D} }[/math] Peclet Number is a dimensionless number relating the rate of advection of a flow to its rate of diffusion, often thermal diffusion. Here we can calculate for Peclet Number, Velocity, Density, Heat Capacity, Characteristic Length, Thermal Conductivity.

Péclet number Two important mechanisms: displacement owing to Brownian motion and shear flow L L timeL/DV=L/Lg=g -1..
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Definition på engelska: Peclet Number Peclet number (PeL) Equation Peclet number (PeL) is the product of Reynolds and the Prandtl number. The Peclet number define the ratio between the advective transport rate and the diffusive transport rate. Giona, M, Adrover, A, Cerbelli, S & Garofalo, F 2009, ' Laminar dispersion at high Péclet numbers in finite-length channels: Effects of the near-wall velocity profile and connection with the generalized Leveque problem ', Physics of Fluids, vol.

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Peclet number Pe = 1/Dispersion number = uL/D. According to dispersion model, dimensionless variance = variance/(mean residence time)^2 = (2/Pe) -(2*(1-e^-Pe)/Pe^2) Please post for further queries

TRW Systems, Redondo Beach, Calif. LOW PECLET NUMBERS FOR THE SOLUTION OF based on its relationship with low Peclet number. alternative to that of low Peclet number based grid.


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It is well known that the Peclet number ( Peclet = u dx / u) must be smaller than 2.0 to maintain numerical stability in a linear convective-diffusive problem, where the convective velocity remains constant. However for a nonlinear problem such as boundary layer flows, as the flow goes away from the wall, the local velocity is increased.

D. is diffusivity, l. is the characteristic length scale (typically channel height) and . U. is the The Kubo number and Peclet number ranges are 1.2–64 and 10–250, respectively.

should be considered. A Péclet number is a dimensionless number than can relate the effectiveness of mass transport by advection to the effectiveness of mass transport by either dispersion or diffusion (Fetter 1999). Usually, diffusion is considered as the dominant transport mechanism for Péclet numbers …

The Péclet number (Pe) is a class of dimensionless numbers relevant in the study of transport phenomena in a continuum. It is named after the French physicist Jean Claude Eugène Péclet. It is defined to be the ratio of the rate of advection of a physical quantity by the flow to the rate of diffusion of the same quantity driven by an appropriate gradient. In the context of species or mass Péclet number Two important mechanisms: displacement owing to Brownian motion and shear flow L L timeL/DV=L/Lg=g -1.. time 2a /D 0 Péclet number = Pe =(a2/D 0)/(g -1) = 6ph 0ga3/kT.

html. Skapa Stäng. A note on electrolysis with forced convection at large peclet number in a channel and an excess of supporting electrolyte  Péclet nummer - Péclet number. Från Wikipedia, den fria encyklopedin. Den Péclet numret ( Pe ) är en klass av dimensionslösa tal relevanta i  forced convection at large Peclet number in a channel with an excess of supporting electrolyte. Russian Journal of Electrochemistry 44 470-478 (Publicerad). in the filtrate, the dispersion coefficients and the Peclet number could be determined; these values were used to calculate local displacement curves.