A simple analytical solution for the steady flow of a third grade fluid in a porous half space

We solve the governing equations for the flow of a third grade fluid in a porous half space. We find a simple expression which describes the solution accurately over the whole domain [0,∞)[0,∞). The rate of exponential decay of the flow is independent of the parameters which characterize the nonlinear part of a third grade fluid. Coefficients in a series expansion depend only on a single material constant.