ORDERLY NATURE OF THE MOTION OF NONSPHERICAL AEROSOL-PARTICLES .2. INERTIAL COLLISION BETWEEN A SPHERICAL LARGE DROPLET AND AN AXIALLY SYMMETRICAL ELONGATED PARTICLE

The efficiency of inertial collision between prolate ellipsoidal particles and a spherical large droplet was calculated. The calculation was performed by simultaneously solving both the equation of translation and the equation of rotation of the spheroids for various initial orientations of the latter. The field of flow around the large droplet was acquired from a previous numerical solution of the Navier-Stokes equation, and the expression for the fluid dynamic torque was taken from Jeffery [Proc. Roy. Soc. 102A, 161-179 (1923)]. The results show a pronounced sensitivity to the initial conditions of orientation. If compared to the collisional efficiencies of a volumetrically equivalent sphere, the efficiencies of the ellipsoidal elongated particles in the investigated cases are up to about 3.5 times greater than the former. The calculational method is applicable to the inertial impaction of any aerosol particle of a general ellipsoid shape which may simulate straight fibers, needles, or oblate (atmospheric) particles of mineral origin. © 1979.