A simple numerical approach for the optimal design of an extrusion die

A simple numerical approach that is based on the lubrication approximation is developed for the optimal design of a linearly tapered coat-hanger die. This approach does not require the analytic pressure drop / flow rate equations for flow in the manifold and in the slot section, therefore any generalized Newtonian fluid model can be easily incorporated. Example calculations have demonstrated that the predictions based on this approach are reasonably accurate as compared with those from the complete 3-D finite element simulations.