Corrugated walls are commonly used as passive devices for heat and mass transfer enhancement, being most effective in applications operated at transitional and turbulent Reynolds numbers. The plate heat exchanger (PHE) is an example of this application. In this thesis work, numerical simulation is used to investigate the heat transfer and pressure drop in plate heat exchangers, with the intention of determining the effect of channel geometry and flow conditions on the heat transfer of the exchangers. In this work two PHEs, one with a wave geometry, and one with a ‘chevron’ design was studied using Fluent as the CFD tool and Gambit as the preprocessor. In both cases, the temperature of the wall was kept constant, water was used as the working fluid, and the mass flow rate varied to study the effect of Reynolds number. The Reynolds number range simulated is 100-25,600.

As shown from the study, different geometries give different results at different flow conditions (Reynolds number/ mass-flow rate). The choice of appropriate plate geometry does not always depend on high Nusselt number values, but predictability and almost constant behaviour through a large Reynolds number range, plays an important role as shown by the chevron design.