[thosmith87]

Hey Guys,

Does any one know the way tecplot calculates the streamlines? I can't figure out how it selects the velocity vectors, or once it selects a vector how it moves to the next vector.

Thanks

[scott_rumage]

Tecplot has some notes on its web-site that may help in this area.

From Tecplot's Knowledge Base http://kb.tecplottalk.com/products/t...e-calculation/ (which has been recently improved) is this note:

Problem: How does Tecplot calculate streamtraces?
Solution: Calculation of streamtraces in Tecplot uses a two-step second-order Runge-Kutta method which may be summarized as follows:
1. The velocity vector direction is calculated at the current particle position.
2. A small step is made (configurable by the user) and the velocity vector direction is calculated at the new location. If necessary the step size is reduced so that no more than one cell is skipped over by the step. The step size is also reduced if a zone boundary is encountered.
3. The vectors obtained in 1 & 2 are averaged and the resulting vector is re-applied at the initial position. The weights of this averaging enforce formal second-order accuracy. To calculate velocities at each point bi- or tri-linear interpolation is used. Refer to the Knowledge Base item on Probing for more details on this interpolation.

A demonstration of calculating streaklines and particles is detailed in this blog entry: http://www.tecplot.com/Community/Blo...reaklines.aspx

Does this answer your question?

Regards,
Scott

[thosmith87]

i had the high concept down, but thank you for the detailed explanation!