TriStream

Compute streamlines on triangular mesh

TRISTREAM Trace streamlines on a triangular mesh using nodal velocities

FlowP=TriStream(tri,x,y,u,v,x0,y0) computes streamlines on the triangular mesh specified by tri with nodal coordinates [x,y]. Streamlines are traced using the nodal velocities u and v, and one streamline is produced for each seed point in the input vectors [x0,y0]. Streamlines are traced until one of four conditions is met: 1) The particle travels beyond the mesh. 2) The particle intersects its own path, creating a cycle. 3) The particle enters a stagnant zone (U~V~0). 4) A maximum number of iterations is exceeded. The output of TRISTREAM is a structure array, FlowP, containing particle flowpaths, and can be displayed using PLOTTRISTREAM.

Algorithm:
TRISTREAM follows the approach outlined in the paper "Efficient Streamline Computations on Unstructured Grids" by Mihai Dorobantu
http://citeseer.ist.psu.edu/40044.html
This algorithm uses a second-order Runge-Kutta method to integrate particle paths with adaptive pseudo-time-stepping.