# Street Canyon Flow

 User Name Remember Me Password
 Register Blogs Members List Search Today's Posts Mark Forums Read

 September 26, 2000, 08:03 Street Canyon Flow #1 mapplekim Guest   Posts: n/a Dear all, I got some data for street canyon flows from numerical model. I found that there is large irregular variation in Reynolds number with increasing turbulent kinetic energy. Is there any other kind of Reynolds number definition? I hope to get your kind answers. Thanks in advance.

 September 26, 2000, 13:39 Re: Street Canyon Flow #2 Adrin Gharakhani Guest   Posts: n/a So long as the flow density and viscosity are constant, the "effective" Reynolds number is fixed. Period. Reynolds number is a scaling parameter that comes from non-dimensionalizing the Navier-Stokes equations. The very idea is so that we'll end up with these "constant" scaling parameters. If you are getting variations in Reynolds number then you are doing something fundamentally wrong in your preliminary analysis (non-dimensionality). Note I stress that the density and viscosity have to be constants. In the simplest case, if, say, you get a kinematic viscosity that is spatially invariant but changes in time, then you get an "effective" Reynolds number that changes in time as well. That is, in front of the Laplacian operator you'll have a term that involves a constant Reynolds number and a time dependent kinematic viscosity, such that their combination gives you a time-dependent Reynolds number. A "simple" example is the iso-thermal flow, say, in an IC engine (where the piston moves sinusoidally and thus the kinematic viscosity changes in time). In this flow, you can clearly see the "thinning" and "thickening" of the wall boundary layers as a function of time, in compliance with the increase and decrease, respectively, of the "effective" Reynolds number. In your canyon flow case I doubt you have a similar situation. Adrin Gharakhani

 September 10, 2013, 14:08 3D street canyon simulation #3 New Member   Prashant Thaker Join Date: Jul 2013 Location: guwahati, India Posts: 15 Rep Power: 4 Hello, i am a new user to Fluent. i am working on pollutant dispersion simulation for a 3D street canyon. Can anyone guide me regarding how to create the Geometry and the boundary conditions. Thanx in advance, prashnat

 Thread Tools Display Modes Linear Mode

 Posting Rules You may not post new threads You may not post replies You may not post attachments You may not edit your posts BB code is On Smilies are On [IMG] code is On HTML code is OffTrackbacks are On Pingbacks are On Refbacks are On Forum Rules

 Similar Threads Thread Thread Starter Forum Replies Last Post kevin FLUENT 8 August 11, 2015 13:00 goodegg Main CFD Forum 12 January 22, 2013 12:47 mireis FLUENT 1 July 28, 2010 05:22 diaw Main CFD Forum 104 February 16, 2006 06:44 L. Könözsy Main CFD Forum 0 April 17, 2000 13:16

All times are GMT -4. The time now is 03:43.

 Contact Us - CFD Online - Top