Effects of Reynolds Number and Aspect Ratio on the Deposition of Airborne Particles on a Quadrilateral Prism

Abstract

Gas velocity distributions around a collector of a large aspect ratio were estimated at different Reynolds numbers from 10 up to 10000. The leading edge separation bubble sizes that were obtained agreed well with the results observated in the literature. The fluctuation in the calculated collection efficiency due to unsteady flow at a high Reynolds number remained witin 16%. The inertial collection efficiency increased with the increase in the Reynolds number, and some increase was even recognized when the Reynolds number was beyond 1000.
Gas velocity distributions around a prism with a medium aspect ratio 0.4 were also calculated at different Reynolds numbers 2, 10 and 50. Although inertial collection efficiencies increased with the increase in the Reynolds number, the increase was found to be slight at Reynolds numbers beyond 10. Inertial collection efficiencies were also found to increase as the aspect ratio increases.
The effects of the Reynolds number and aspect ratio on the gravitational collection efficiency were found to be insignificant. The calculated collection efficiencies were verified experimentally,