Novel measurement system for Particle Image Velocimetry based on three-color pulsed lamps and image processing

In the last few years Particle Image Velocimetry (PB) has become one of the most useful techniques for the study of flowfields. In 2D applications, it allows the simultaneous measurement of the velocity distribution on the whole acquisition area. Currently the main limits to a further diffusion of this technique are economic and safety issues. Laser illumination, commonly used for PIV measurement systems, is expensive and the use of laser beams is limited by a certain number of problems, mainly by safety and economical reasons. Other typical aspects of PIV techniques are its limits on the velocity range that can he measured simultaneously with adequate accuracy and the difficulty in using relatively thick light sheets. We propose a relatively new and nicely working PIV measurement system based on flashed lamps as light source and digital reconstruction of particle positions by linage processing. Three different colors are used In order to distinguish, on a same photograph, the corresponding positions of each moving particle at three different Instants of time. This solution can give significant advantages in several aerodynamic and hydrodynamic situations. In particular, it allows high flexibility for velocity measurements and independent setting of different acquisition parameters, like pulse powers and timing. Furthermore, the developed PIV measurement system is fully transportable, eye-safe, practical, and economical.