Pressure drop predictions on the shell side of a shell and tube heat exchanger (STHX) are investigated using the concept of Finite Element Method (FEM). In this model the shell side region is discretised into a number of elements and by taking into account the effect of flow pattern, the pressure drop on the shell side of a STHX is determined. The present method is simple to apply and the predictions agree reasonably well with a large number of experimental data available in the literature. The range of applicability of the present method extends beyond that used by others in the literature. The earlier predictions were restricted to tubes in the window region, however, the predictions of the present method are extended to the cases of no tubes in the window (NTIW) region also. (C) 2015 Elsevier Ltd. All rights reserved.