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

Smooth rectabgular duct - Simulation vs. Literature correlations

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   July 7, 2011, 06:59
Default Smooth rectabgular duct - Simulation vs. Literature correlations
  #1
Member
 
Luca
Join Date: Mar 2011
Location: Italy
Posts: 62
Rep Power: 15
marluc is on a distinguished road
Hallo,

I have done simulations of a turbulent air flow in a smooth rectangular duct. I compared my numerical results of pressure drop (friction factor) with literature correlations.

Here follows a brief summary of my simulation (because of symmetry I have only simulated one-fourth of the duct):

Fluid: air with costant properties
Turb model: k-w standard
y+: everywhere below 2.5 and above 0.8
Inlet B.C.: mass flow inlet
Outlet B.C.: outflow
Reynolds number: 7666

I compared my results for the pressure drop (or friction factor) with some literature correlations, e.g. f=(1.82*log_10 Re -1.64)^-2 (Gnielinski) and I have foud a mean discrepancy of 12%.

I have also performed a sensitivity analysis on the grid but the results do not change.

Can anyone inform me if such a discrepancy is acceptable or if it is typically possible to obtain a better agreement between numerical simulation and literature correlation for the friction factor (or pressure drop)?

Thank you in advance,
marluc
marluc is offline   Reply With Quote

Old   September 22, 2023, 08:07
Default
  #2
New Member
 
Alex Lee
Join Date: Aug 2023
Posts: 7
Rep Power: 3
CFDbeginer is on a distinguished road
Hello, I'm sorry to bother you. Although this has been a post for many years, I have also encountered similar situations. Can you tell me how you resolved this issue in the end?
CFDbeginer is offline   Reply With Quote

Old   September 25, 2023, 12:36
Default
  #3
Senior Member
 
Erik
Join Date: Feb 2011
Location: Earth (Land portion)
Posts: 1,183
Rep Power: 23
evcelica is on a distinguished road
You have to make sure you are comparing apples to apples.
Make sure your inlet or outlet effects are not influencing your results comparisons, and total pressure effects from changing cross sections or compressible flows are also considered correctly in the comparison.
evcelica is offline   Reply With Quote

Reply

Tags
pressure drop, smooth duct, turbulent flow, validation


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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Fabric Duct Modeling Dan FLUENT 1 September 27, 2024 04:43
Sample simulation of axial flow impeller in a duct Vashishth CFX 1 November 16, 2008 20:34
2D simulation of circular and rectangular duct mvee FLUENT 4 March 24, 2007 00:40
flow simulation across a small fan jane luo Main CFD Forum 15 April 12, 2004 18:49
2D diverging duct simulation venugopal Main CFD Forum 0 November 2, 2001 19:49


All times are GMT -4. The time now is 05:27.