The flow characteristics between two interactive spheres

The influences of a surrounding sphere of different size, located at various distances and angles, on the drag and the flow characteristics of a test sphere have been experimentally investigated. The liquid viscosity is increased in an effort to enlarge the magnitudes of drag to a measurable range. The drags of an interactive particle can then be actually determined by the help of a:precise electronic balance. Flow-field measurements are conducted using a non-intrusive LDA system. The refractive index matching technique is applied to overcome the optical difficulty caused by the passage of a laser beam through a curve surface. Empirical correlations are developed to calculate both the form and the friction drags of an interactive particle. Flow properties under different interactive conditions are closely related. (C) 1999 Elsevier Science Ltd. All rights reserved.