PARAMETRIC STUDY OF PARTICLE DEPOSITION IN SINUSOIDAL PORES OF ARBITRARY ORIENTATION

A parametric study of particle deposition during flow of suspensions through single constricted pores is presented in order to identify the effects of the various forces acting on the particles on the simulated deposition rate and to assess the sensitivity of the filtration efficiency predictions on the uncertainty involved when evaluating the relevant parameters. The calculations of the impacted particle fraction are based on the calculation of 3-D particle trajectories in sinusoidal tubes under the action of hydrodynamic forces and torques, gravity, the double ionic layer force, and the London force. It is found that the five dimensionless parameter groups that enter the calculation of the surface forces affect the deposition rate in a similar manner. Two distinct regions can be identified for each group; in each region the impacted fraction remains almost insensitive to changes in the group value. However, transition from one region to the other causes a spectacular, abrupt change of the impacted fraction by more than five orders of magnitude. Among the main conclusions of this parametric analysis is that the determination of the filtration efficiency rests mainly on the easily measured gravitational group and is insensitive to the precise value of the five surface force parameter groups, as long as it is known that each of them is larger or smaller than a corresponding critical value given here. Finally, the impacted fraction up to various depths into a unit cell and the impacted fraction per unit length are calculated for vertical and horizontal cells and for variable particle size. © 1993 Academic Press, Inc.