The paper presents a finite element model for the solution of the three-dimensional, time-dependent Navier-Stokes equations. Isoparametric brick elements are used, with tri-linear interpolation for both velocity and pressure. A fractional-step algorithm is applied, and the advection-diffusion part of the system is solved using a two-step Taylor-Galerkin formulation. The pressure is computed from a Poisson equation, which is solved numerically using a preconditioned conjugate gradient method.