Heat exchangers are components used to transfer heat between fluid streams at different temperatures. These are important in refrigeration systems because they are associated with irreversibilities, that must be minimized in order to maintain an optimal thermodynamic performance of the system.
The effectiveness of the condensers and evaporators affects directly the performance of the refrigeration system. Such effectiveness depends, basically, on the technology, the geometry and the convection mode: natural or forced. Natural convection heat exchangers are usually larger, since there is no fan attached to it. On the other hand, forced-draft condensers are compact, with high heat transfer rate per volume.
The forced-draft fin-on-tube evaporators are extensively used in no-frost household refrigerators. Natural-draft condensers, such as skin or wire-on-tube, or forced-draft condensers, such as wire-on-tube or micro channel, are also commonly used in this kind of appliance.
The research projects at POLO are dedicated to the development and evaluation of new geometries of heat exchangers with objectives of increasing performance and reducing material and manufacturing costs.