CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > Siemens > STAR-CCM+

Pressure Drop due to Friction

Register Blogs Members List Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   April 29, 2012, 23:22
Default Pressure Drop due to Friction
  #1
New Member
 
sam
Join Date: Nov 2011
Posts: 25
Rep Power: 13
Sam0508 is on a distinguished road
Hi,
Let me Explain the conditions of problem.

Pipe 4mm, Air velocity 50m/s, Turbulent flow, Dy viscosity 1.79E-5 N.S/m2, Density of Air 1.23kg/m3.Need of finding the Pressure Drop for 0.1m length.

The Calculation value is 1.076kPa,but in STAR CCM+ got value as 1.255kPa.In software i specified the B.C as Inlet-Velocity inlet 50m/s and outlet-massflow outlet -7.539E-9 kg/s and mentioned Roughness Height also for account of friction factor.

In physics continuum..Constant density/Segregated flow/Steady state/K-Epsilon Turbulence.

Can u tell me what i did wrong in software?



Thankyou,
Sam0508
__________________
Regards,
Sam
Sam0508 is offline   Reply With Quote

Old   April 30, 2012, 09:49
Default
  #2
Member
 
Ryan Coe
Join Date: Jun 2010
Location: Albuquerque, NM
Posts: 98
Rep Power: 14
ryancoe is on a distinguished road
What is your 'calculation' value (is it from an empirical experiment)? If so, the CFD and empirical calculation should not necessarily be expected to match exactly.
__________________
Ryan
ryancoe is offline   Reply With Quote

Old   May 2, 2012, 01:30
Default Pressure drop due to friction
  #3
New Member
 
sam
Join Date: Nov 2011
Posts: 25
Rep Power: 13
Sam0508 is on a distinguished road
Quote:
Originally Posted by ryancoe View Post
What is your 'calculation' value (is it from an empirical experiment)? If so, the CFD and empirical calculation should not necessarily be expected to match exactly.

----****----

Hi Ryan Coe,
It's not a experimental value, found by normal Dp(Pressure drop) Derived equation.i.e

Dp=(f*L*rho*V2)/(2*D) Dp units Pa
[f= friction factor(beased on Reynolds No and Relative Roughness), L=Pipe lenght 0.1m, rho=Density of Air, V= velocity of air 50m/s and D=Pipe diameter]

Why this values is not match with Theoritical data/Derived one.the difference(STAR CCM+ result Dp-Theoritical Dp result) is 170Pa,how we can accept? or What i did mistakes in this. Plz give ur feedback.Thankyou
__________________
Regards,
Sam
Sam0508 is offline   Reply With Quote

Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

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
Pressure drop due to contraction and a subsequent expansion lionel89 Main CFD Forum 0 February 13, 2012 06:34
Pressure drop? Munni FLUENT 4 March 25, 2010 14:21
Pressure drop match praveen.jpk FLUENT 3 September 11, 2009 03:36
Pressure Drop in outlet Vent Abdul FLUENT 2 October 28, 2008 12:13
Hydrostatic pressure in 2-phase flow modeling (CFX4.2) HB &DS CFX 0 January 9, 2000 13:19


All times are GMT -4. The time now is 04:24.