Effect of a cylindrical boundary on a fixed rigid sphere in a moving viscous fluid

In this investigation of the effect of a cylindrical boundary on a spherical particle suspended in a moving viscous fluid the pressure drop due to the motion of fluid past a stationary sphere and the drag on the sphere are independently measured, and the sphere- to-cylinder-diameter ratios varying from 0.1250 to 0.3125 are studied at different positions of eccentricity. The investigation shows that in the range of Reynolds numbers from 0.1 to 40.0, based on the approach velocity to the sphere and the diameter of the sphere, the pressure drop due to the presence of a sphere and the drag on it can be represented by a semiempirical relationship containing two terms. One term, owing to the effect of the cylindrical boundary, is derived theoretically from the creeping-motion equations which neglect inertial effects. The second term, owing to the inertial effects, is established from data on the drag coefficient of a sphere in on unbounded medium.