# Purpose of streamlines in unsteady flow

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

 January 31, 2011, 18:29 Purpose of streamlines in unsteady flow #1 Senior Member   TWB Join Date: Mar 2009 Posts: 148 Rep Power: 10 Hi, I have seen diagrams of airfoil with streamlines drawn. It helps to show the velocity vectors of the flow around the airfoil. However, does streamlines help in the analysis of unsteady flows, such as an airfoil moving up and down? Is there any useful information which can be extracted? Thanks!

 February 1, 2011, 11:30 #2 Member   private Join Date: Mar 2009 Posts: 74 Rep Power: 10 Streak lines can be useful for visualization. One way: Create an imaginary particle at points of interest (x, y). Follow the particle in a Lagrangian frame. Example: Dx/Dt = u, Dy/Dt = v, Dz/Dt = w so x(t+dt) = x(t) + u*Dt, etc. following the particle through the flow. The three equations can be integrated explicitly [use u(x, t)], implicitly [use some combination of u(x,t) and u(x+dx, t+dt) estimates]. The u's, v's and w's are interpolated from your CFD solutions at the various (x,y,z,t). Implicit schemes and various Runge-Kutta schemes are available. I'm sure other folks will correct, extend, and clarify this outline! otd

 Thread Tools Display Modes Linear Mode

 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 OffTrackbacks are On Pingbacks are On Refbacks are On Forum Rules

 Similar Threads Thread Thread Starter Forum Replies Last Post Ben CFX 5 January 17, 2008 18:04 HT Main CFD Forum 1 February 25, 2004 13:29 wieke Main CFD Forum 0 September 30, 2003 04:40 faithkim Main CFD Forum 3 September 14, 1999 20:57 Tylor Xie Main CFD Forum 0 June 9, 1999 07:33

All times are GMT -4. The time now is 17:35.