A numerical investigation of performance and optimization trends of direct contact heat exchangers

A numerical model has been developed that can be used for industrial design of a wide range of direct contact heat exchangers (DCHXs). This model is built from some earlier work where a one-dimensional model was used to describe some very specific and limited DCHX spray-column configurations. Changes to the initial model are proposed to reflect more accurately the physics of the flows found in both two- and three-phase DCHXs. In addition, generalizations are incorporated into the model to be able to analyze a wide variety of fluid combinations and roles (either as the dispersed flow or as the continuous fluid). A major effort is directed to the development of an optimization that can handle the complete variety of fluids and configurations for spray columns. Parametric evaluations are then performed to demonstrate that the model does indeed perform appropriately, and comparisons are made to existing experimental data. Finally, an extension to a more complicated configuration is made where the two-dimensional effects of a sieve-tray-tower exchanger are incorporated. This latter aspect is the first step in developing multidimensional models