CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > SU2

Confused by the Reynolds_length and Reynolds_number

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   November 29, 2015, 02:52
Default Confused by the Reynolds_length and Reynolds_number
  #1
New Member
 
Boping M.
Join Date: Aug 2014
Location: China
Posts: 11
Rep Power: 11
BopngMa is on a distinguished road
Hello,

Currently I am using the SU2 to do some tests. And some configure confused me, so I need your help.

First, for the Reynold number setting, the newest version SU2 gives this:

% Reynolds number (non-dimensional, based on the free-stream values)
REYNOLDS_NUMBER= 6.5E6
%
% Reynolds length (1 m by default)
REYNOLDS_LENGTH= 1.0

and since the equation to get Reynold number is Re=rho*v*L/viscousity, the value of the Reference length “L” in this equation is set by users? For example, I am doing a 3 dimensional computation, the model is the Lockheed Seeb-ALR. I generated two grid of the model, with the model length being 17.68in and 1768mm, and for the first situation, I set the Reynolds_length as 1.0 and set the Reynolds_number to 3.63E5 (which is from 6.42/17.68) and for the second condition I set Reynolds_length to 100, and set the same Reynolds_number. Is it ok?

Actually, in the second situation, I used the reynolds_length as a scale. How will this influence the result?

Thanks
Attached Images
File Type: png 1.png (126.8 KB, 16 views)
File Type: png 2.png (27.2 KB, 10 views)

Last edited by BopngMa; November 29, 2015 at 02:53. Reason: correction spelling
BopngMa is offline   Reply With Quote

Old   February 23, 2016, 11:59
Default
  #2
hlk
Senior Member
 
Heather Kline
Join Date: Jun 2013
Posts: 309
Rep Power: 13
hlk is on a distinguished road
Quote:
Originally Posted by BopngMa View Post
Hello,

Currently I am using the SU2 to do some tests. And some configure confused me, so I need your help.

First, for the Reynold number setting, the newest version SU2 gives this:

% Reynolds number (non-dimensional, based on the free-stream values)
REYNOLDS_NUMBER= 6.5E6
%
% Reynolds length (1 m by default)
REYNOLDS_LENGTH= 1.0

and since the equation to get Reynold number is Re=rho*v*L/viscousity, the value of the Reference length “L” in this equation is set by users? For example, I am doing a 3 dimensional computation, the model is the Lockheed Seeb-ALR. I generated two grid of the model, with the model length being 17.68in and 1768mm, and for the first situation, I set the Reynolds_length as 1.0 and set the Reynolds_number to 3.63E5 (which is from 6.42/17.68) and for the second condition I set Reynolds_length to 100, and set the same Reynolds_number. Is it ok?

Actually, in the second situation, I used the reynolds_length as a scale. How will this influence the result?

Thanks
Please see:
http://www.cfd-online.com/Forums/su2...enght-su2.html
hlk is offline   Reply With Quote

Reply


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 Off
Trackbacks are Off
Pingbacks are On
Refbacks are On



All times are GMT -4. The time now is 10:17.