Positron Emission Particle Tracking (PEPT) Validation for Jet Flow

Abstract

Positron Emission Particle Tracking (PEPT) generates 4D Lagrangian particle trajectories and is increasingly used to evaluate flow in granular media and complex geometries where optical interrogation methods are not possible. A Multi-Particle PEPT (Multi-PEPT) approach was developed capable of finding and tracking many particles simultaneously to extend the utility of the PEPT method. This paper compares 4,014 trajectories generated using the Multi-PEPT method with 3,055 trajectories generated from High Speed Video (HSV) data. All trajectories are taken in an acrylic test section with water flow using resin beads. The flow geometry includes a flow restriction producing a jet of Reynolds number 23,500 ±800, with peak velocity near 2 m/s, and two recirculation zones. Variation between measurement outcomes is generally less than 0.1 m/s, and measured variations fall within measurement uncertainties. Data co-location uncertainty contributes to larger variations between Multi-PEPT and HSV velocities in regions of steep gradients.

A feature point identification method for positron emission particle tracking with multiple tracers

“…Experimental testing has begun using the Siemens Inveon PET scanner [10]. Experiments will be conducted to test the performance of our current methods for flow characterization.…”

“…Since the acquisition of the above data, a Siemens Inveon prelinical PET scanner has been acquired by the University of Tennessee, and PEPT experiments have been conducted using this machine [10]. Similar to the P4, the Inveon is made up of 64 detector modules arranged in a cylinder of diameter 16.1 cm and length 12.7 cm.…”

“…In order to achieve this, higher activity tracer particles are used in physical measurements. In this experiment, the sources were of activity only 7 μCi, whereas in physical flow experiments, tracers used are of activity of order 1 mCi [9,10].…”

“…Such a measurement technique could be used for Lagrangian flow measurements in which multiple tracer particles can pass through a test section as part of a recirculating flow loop. Wiggins, et al [8] developed such a method for multiple particle tracking, and this has been used to study both vortical flow in a transparent test section [9] and jet flow induced between baffle plates [10]. In this paper, a new method for multiple particle tracking is introduced and compared to the previous.…”