Abstract
An analytic technique, namely the homotopy analysis method, is
applied to solve the Navier–Stokes equations governing unsteady viscous flows
due to a suddenly stretching surface in a rotating fluid. Unlike perturbation
methods, the current approach does not depend upon any small parameters at all.
Besides contrary to all other analytic techniques, it provides us with a simple
way to ensure the convergence of solution series. In contrast to perturbation
approximations which have about 40% average errors for the considered problem,
our series solutions agree well with numerical results in the whole time region
0⩽t<+∞.
Explicit analytic expressions of the skin friction coefficients are given, which
agree well with numerical results in the whole time region
0⩽t<+∞.
This analytic approach can be applied to solve some complicated
three-dimensional unsteady viscous flows governed by the Navier–Stokes
equations.