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

Womersley pulsatile boundary condition for blood flow.

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   August 5, 2011, 02:03
Default Womersley pulsatile boundary condition for blood flow.
  #1
Member
 
Guifan Li
Join Date: Apr 2011
Location: New York City, U.S.
Posts: 96
Rep Power: 15
liguifan is on a distinguished road
Dear all,

I know this topic is discussed before, but I didn't find solutions. So please bear with me.

I try to use groovyBC to implement this function but:

The womersley formula include a Bessel function which need to be passed into a imaginary complex number. To my knowledge, Bessel function under OpenFOAM J0(s) can only solve the real number. And I don't know how to transfer womersley function to real domain.

I write a matlab code to simulate the womersley pulsatile flow that I want. (besselj can resolve imaginary complex number). But that's it, no idea how to corporate my mat-lab data with OpenFOAM since the data is dependent on both t (time) and y (position).

I have beening struggling with this for a while and quite frustrated...

Can anyone give some help or hint please?
liguifan is offline   Reply With Quote

Old   August 5, 2011, 03:47
Default
  #2
Senior Member
 
Elvis
Join Date: Mar 2009
Location: Sindelfingen, Germany
Posts: 620
Blog Entries: 6
Rep Power: 24
elvis will become famous soon enough
Hello,

have you tried to play around with pythonflu?
http://pythonflu.wikidot.com/ maybe it gives you some opportunities that might be of value to you.
elvis is offline   Reply With Quote

Old   August 5, 2011, 06:02
Default
  #3
Member
 
Guifan Li
Join Date: Apr 2011
Location: New York City, U.S.
Posts: 96
Rep Power: 15
liguifan is on a distinguished road
Quote:
Originally Posted by elvis View Post
Hello,

have you tried to play around with pythonflu?
http://pythonflu.wikidot.com/ maybe it gives you some opportunities that might be of value to you.
Hi elvis,

Thanks for your reply, I went to pythonflu, is seems like can integrate with Matlab results. But I didn't find any manual of pythonflu.

Can you please suggest me in some details how to solve womersley inlet in pythonflu. Do I need to import data from matlab or I can just write some function in pythonflu?

Cheers!
liguifan is offline   Reply With Quote

Old   August 5, 2011, 07:06
Default
  #4
Assistant Moderator
 
Bernhard Gschaider
Join Date: Mar 2009
Posts: 4,225
Rep Power: 51
gschaider will become famous soon enoughgschaider will become famous soon enough
Quote:
Originally Posted by elvis View Post
Hello,

have you tried to play around with pythonflu?
http://pythonflu.wikidot.com/ maybe it gives you some opportunities that might be of value to you.
But it will only help him if he manages to interface to Matlab as pythonflu is "only" a wrapper around OpenFOAM it won't be able to calculate the complex Bessel-Function
gschaider is offline   Reply With Quote

Old   August 5, 2011, 07:32
Default
  #5
Member
 
Guifan Li
Join Date: Apr 2011
Location: New York City, U.S.
Posts: 96
Rep Power: 15
liguifan is on a distinguished road
I forgot to say is that the Womersley number is known in my experiment.
Attached Images
File Type: jpg womersleyformula.jpg (43.3 KB, 140 views)

Last edited by liguifan; August 5, 2011 at 09:56.
liguifan is offline   Reply With Quote

Old   August 5, 2011, 09:55
Default
  #6
Member
 
Guifan Li
Join Date: Apr 2011
Location: New York City, U.S.
Posts: 96
Rep Power: 15
liguifan is on a distinguished road
Quote:
Originally Posted by gschaider View Post
But it will only help him if he manages to interface to Matlab as pythonflu is "only" a wrapper around OpenFOAM it won't be able to calculate the complex Bessel-Function
Hi Bernhard,

Do you think I can use the following formula which which is in real domain to implement the Womersley solution so that I can pass into groovyBC.

Many thanks
Attached Images
File Type: jpg womersleyformula.jpg (43.3 KB, 56 views)
liguifan is offline   Reply With Quote

Old   August 8, 2011, 05:40
Default
  #7
Assistant Moderator
 
Bernhard Gschaider
Join Date: Mar 2009
Posts: 4,225
Rep Power: 51
gschaider will become famous soon enoughgschaider will become famous soon enough
Quote:
Originally Posted by liguifan View Post
Hi Bernhard,

Do you think I can use the following formula which which is in real domain to implement the Womersley solution so that I can pass into groovyBC.

Many thanks
If the computer algebra program of your choice (or you calculating by hand) gives back a reasonable expression for the closed part (like "Re[u[y,t]]" in Mathematica) there should be no problem. I only glanced at your formula and I don't quite get what sould make it complex anyway (if t and y are real)
gschaider is offline   Reply With Quote

Old   August 10, 2011, 06:59
Default
  #8
Member
 
Guifan Li
Join Date: Apr 2011
Location: New York City, U.S.
Posts: 96
Rep Power: 15
liguifan is on a distinguished road
Quote:
Originally Posted by gschaider View Post
If the computer algebra program of your choice (or you calculating by hand) gives back a reasonable expression for the closed part (like "Re[u[y,t]]" in Mathematica) there should be no problem. I only glanced at your formula and I don't quite get what sould make it complex anyway (if t and y are real)
Thanks for the explanation, I find the formula from somewhere else. I havn't aprove the validation of that one, but I got a parabolic velocity inlet varying with time, which is quite good. I try the Mathematica, but it can not give you expression when input something like
"FullSimplify[Re[u[y,t]]]" , the return value is still in the form of "Re[...]". I will put more time on this see whether can I get a nice derivation.

Thanks again for your help!
liguifan 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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Wind turbine simulation Saturn CFX 58 July 3, 2020 01:13
mass flow in is not equal to mass flow out saii CFX 12 March 19, 2018 05:21
Need Help on boundary condition in Multi-Phase flow creddy_trddc CFX 0 December 9, 2010 07:53
Swirling flow as a boundary condition hami9293 FLUENT 0 November 2, 2010 07:09
Convective Heat Transfer - Heat Exchanger Mark CFX 6 November 15, 2004 15:55


All times are GMT -4. The time now is 11:37.