Couple stress fluid past a contaminated fluid sphere with slip condition

In this article, an exact solution for couple stress fluid flow past a contaminated fluid sphere, filled with couple stress fluid was formed by using interfacial slip boundary condition. It's involved with internal and external cap and no cap regions. The velocity is expressed in terms of stream function. The external velocity and internal velocity are obtained. The Drag coefficient is computed. The special cases of a viscous fluid with a no-slip condition, solid sphere case are evaluated. The obtained results are in good agreement with the results from the literature. Additionally studied viscous fluid past a contaminated couple stress fluid sphere and couple stress fluid past a contaminated viscous sphere, also done. The results of special cases are also agreeing with the results from the literature.(c) 2023 Published by Elsevier Inc.