US Patent 7228699 Plate heat and mass exchanger with edge extension

Heat exchanger plates for indirect evaporative coolers, of the type having a dry side having low permeability to an evaporative liquid and formed to allow a product fluid to flow over a heat transfer area of its surface, a wet side designed to have its surface wet by an evaporative liquid, and formed to allow a working gas to flow over its surface to evaporate the evaporative liquid, further include edge extensions formed beyond the heat exchange area of the plates to facilitate removal of excess evaporative liquid. The edge extensions may slant or curve away from the wet side of the plates to assist in liquid removal. The plates may be used in a variety of configurations.