PT123: A Multi-Dimensional Particle Tracking Computer Program, Version 1.0

• Main Authors: Cheng, Hwai-Ping, Farthing, Matthew W, Winters, Kevin D, Howington, Stacy E, Cheng, Jing-Ru C, Hines, Amanda
• Format: Report
• Language: English
• Subjects: ADAPTIVE SYSTEMS; ADAPTIVE TIME INTEGRATION; Computer Programming and Software; COMPUTER PROGRAMS; ELEMENT-BY-ELEMENT TRACKING; MESH; MULTI-DIMENSIONAL TRACKING; NON-ELEMENT-BY-ELEMENT TRACKING; PARTICLE TRACKING; PARTICLES; PT123; RUNGE KUTTA METHOD; TRACKING; TRACKING ALONG CLOSED BOUNDARIES; UNSTRUCTURED MESHES; USER NEEDS; VELOCITY

This report describes a particle tracking computer program named PT123. The development of PT123 was supported in part by the Civil Works Basic Research project entitled Efficient Resolution of Complex Transport Phenomena Using Eulerian-Lagrangian Techniques and in part by the System-Wide Water Resources Program (SWWRP). Given velocities, PT123 can track massless particles in 1-, 2-, and 3-D unstructured or converted structured meshes. The elements used to construct PT123 meshes are line elements in 1-D, triangular and/or quadrilateral elements in 2-D, and tetrahedral, triangular prism, and/or hexahedral elements in 3-D. One adaptive (embedded 4th- and 5th-order) and three non-adaptive (1st-, 2nd-, and 4th-order) Runge-Kutta (RK) methods are included in PT123 to solve the ordinary differential equations describing the motion of particles. The adaptive RK method allows the user to control tracking accuracy with specified error tolerances. The nonadaptive RK methods provide the user options to balance computational efficiency and accuracy by using lower order schemes for smooth velocity fields and higher order schemes for complex velocity fields. Both elementby- element (EBE) and non-element-by-element (NEBE) tracking approaches are incorporated into PT123. The original document contains color images.