Shake-The-Box particle tracking with variable time-steps in flows with high velocity range (VT-STB)

We present a novel evaluation mode for Lagrangian Particle Tracking methods in general, applied to the Shake-The-Box method specifically. The aim is to attain high levels of accuracy and a removal of false (‘ghost’) tracks in flow situations, where significant amounts of particles show small relative movement with respect to each other in consecutive time-steps. An iterative approach using variable time separations is employed, which starts by tracking particles at high timeseparations, followed by an iterative reduction of time separation, while feeding the particle tracked within the previous iterations. The process allows for applying tracking parameters fine-tuned to the different flow regimes tracked within each iteration. Experimental validation was performed using a dataset on impinging jet flow, created in collaboration with the School of Mechanical Engineering of Pusan National University. Evaluation of this flow with high velocity range shows distinct advantages in reduction of ghost tracks and in tracking accuracy.