CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > General Forums > Main CFD Forum

pressure modeling on Microcantilever

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   February 7, 2007, 15:50
Default pressure modeling on Microcantilever
  #1
Hadi Yagubizade
Guest
 
Posts: n/a
I have a problem in my project and is : I have a microcantilever beam that is in plat.i have two force that act to this beam, 1. magnetic force from bottom and 2. flow drag force that act to cantilever when it bend in effect of magnetic force. i can model the magnetic force and is non-linear , for this matter i must model drag effect and after that i solve that in same time. but i can't model the drag force on microcantilever beam. in your opinion how can i model drag force.?

thanks

  Reply With Quote

Old   February 7, 2007, 17:00
Default Re: pressure modeling on Microcantilever
  #2
Harish
Guest
 
Posts: n/a
You can compute the drag force with a flat plate approximation.But since your problem is a microcantilevel, you might need to include a partial slip correction at the boundary for the computed drag.Have a look at any book on microflows to calculate slip correction.The drag on a flat plate can be found in any fluid mechanics book.

  Reply With Quote

Old   March 6, 2007, 02:44
Default Re: pressure modeling on Microcantilever
  #3
H. Yagubizade
Guest
 
Posts: n/a
Thanks for your answer. I want to discribe more about my problem. with attention to this point that my microcantilever is horizontal and the flow also is, and with out of magnetic force i don't have drag force on it becouse the cantilever is prallel with flow, but after bending with magnetic force from bottom, now we have drag force, similar that i take quarter cylinder on opposite of flow in boundary layer(becouse is Micro). i want that you help me more, if possible and i can't find any reference , if you have any reference , i wait you.

sincerly

  Reply With Quote

Old   March 6, 2007, 09:34
Default Re: pressure modeling on Microcantilever
  #4
Harish
Guest
 
Posts: n/a
when you have flow over the cantilever, you have the skin friction drag even without the magnetic force.So I assume that the drag might be a sum of skin friction drag and drag due to the bending caused by magnetic forces.You can obtain the drag for microflows by replacing u with u+alpha*du/dn,where du/dn is to account for the partial slip which happens in microflows.More about it can be found in Microflows book by Karniadakis and Beskok.Regarding the magnectic part,look into the book of lifshitz,"Fluid mechanics".He might have given some analytical solution for magnetic drag.

  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 Inlet" Boundary Setup Wijaya FLUENT 15 May 18, 2016 11:08
Pressure Rise Error emueller CFX 0 May 5, 2009 12:08
cavitation modeling and pressure distribution arazgaldy FLUENT 2 July 26, 2006 03:29
Gas pressure question Dan Moskal Main CFD Forum 0 October 24, 2002 23:02
Definition of pressure Ola Nordblom FLUENT 1 August 16, 2001 16:58


All times are GMT -4. The time now is 17:34.