Trefry, M.G., and Townley, L.R. (1996). Tools for empirical analysis of steady flux fields: PTRACK and STREAMv2.0. CSIRO Division of Water Resources Technical Memorandum 96/13, 64pp., June.

The lack of a uniquely defined streamfunction for solutions to the threeÐdimensional Laplace and Poisson equations forces the use of less direct methods in classifying and quantifying the topologies of the solution flow regimes. Particle tracking techniques, using advecting massless point particles, are commonly used in such circumstances. This report describes the development and application of two tools based on such particle tracking techniques. The first, PTRACK, is a simple Eulerian particle tracking code designed to handle input velocity distributions calculated by standard finite difference codes. The second, STREAMv2.0, is a superset of PTRACK with built-in logic for locating dividing streamsurfaces and storing their geometries in ASCII form for later imaging/rendering. Whilst each tool is written to handle specific input and output file formats, the modular nature of the code ensures that the task of altering the code to handle new formats is quite small. Applications of the two tools are discussed and results are presented.