A computer algorithm was developed to simulate two- and three-dimensional fluid flow and heat transfer in the shell-side of single- and two-phase shell-and-tube heat exchangers.

The governing equations are solved in primitive variable form using a semi-implicit consistent formulation in which a segregated pressure correction linked algorithm is employed.

Numerical predictions are obtained for isothermal, two-dimensional, axisymmetric, turbulent flow in a single-phase experimental disc-and-doughnut heat exchanger. The system consists of alternating and equi-spaced doughnut and disc baffles located in a pipe with water flowing in turbulent regime. The two-equation (k-e) turbulence model as proposed by Nagano and Hishida is modified to accommodate disc and doughnut baffles.

The proposed modified Nagano and Hishida's (k-e) model leads to considerable computer time saving and better predictive capability when compared to original Nagano and Hishida's (k-e) model for the fluid flow in multibaffled regions.

Also, four different types of two-phase shell-and-tube heat exchangers, steum condensers, are modelled;​ the numerical predictions are critically assessed by comparison against available data for an experimental condenser and a power plant condenser. The results indicate that solutions obtained by employing the numerical technique developed in this study are in good agreement with experimental data.