The coagulation rate of a dilute polydisperse aerosol dispersion of particles is considered for small Peclet number, which provides a measure of the ratio of the relative sheareinduced motion to Brownian motion betWee...The coagulation rate of a dilute polydisperse aerosol dispersion of particles is considered for small Peclet number, which provides a measure of the ratio of the relative sheareinduced motion to Brownian motion betWeen two rigid spherical aerosol particles.The asymptotic form of the relative velocity of tWo unequal particles immerse in a simple shear flow when they are far apart is obtained.Using a singular pertllrbation method,a tWo term expansion for the dimensionless coagulation rate(Nusselt number) as function of the Peclet number is developed.In the limit of the radius of one of the two spheres becoming small,the result agrees with the dimensionless mass transfer rat6 to an aerosol particle at small Peclet number.展开更多
文摘The coagulation rate of a dilute polydisperse aerosol dispersion of particles is considered for small Peclet number, which provides a measure of the ratio of the relative sheareinduced motion to Brownian motion betWeen two rigid spherical aerosol particles.The asymptotic form of the relative velocity of tWo unequal particles immerse in a simple shear flow when they are far apart is obtained.Using a singular pertllrbation method,a tWo term expansion for the dimensionless coagulation rate(Nusselt number) as function of the Peclet number is developed.In the limit of the radius of one of the two spheres becoming small,the result agrees with the dimensionless mass transfer rat6 to an aerosol particle at small Peclet number.