Grant: Research Tools and Instruments

Multiphase flows and specifically sprays have been acknowledged as an important phenomenon integral to many technological and natural systems. Among them are agricultural sprays, inhaled drug delivery systems, thermal spray coating, etc. One of the most effective instruments available for characterizing the droplet size and velocity distribution in such systems is a two-component Phase Doppler Particle Analyzer (PDPA). The Phase Doppler Method is based upon the principles of light scattering interferometry. Measurements are made at a small, non-intrusive optical probe volume defined by the intersection of two laser beams. The intersection of the two beams creates a fringe pattern within the probe volume. As a droplet (or particle) passes through the probe volume, it scatters light from the beams and projects the fringe pattern. The application of the proposed equipment is for the research on i) the development of functional and environmental protective coatings produced by the emerging suspension thermal spray processes, ii) advancement of the liquid accelerated cold spray (LACS) deposition system, iii) design the next-generation spray nozzles for more efficient injection and transportation of suspensions and complex fluids of nanoparticles in high speed flows, and iv) study of the COVID-19 transmission via respiratory droplets. By measuring the particle velocity and size distributions, we will develop correlations relating these parameters to the spray nozzle design, the inlet flow conditions as well as risk of transmission of the COVID-19 virus through respiratory droplets. Such correlations will not only be used by industry and health sectors, but will allow us to validate our numerical results and better understand the relationship between various governing parameters and the spray characteristics. The results of this study will facilitate manufacturing of key aerospace, automotive, and biomedical components, all of which are important to the Canadian economy.