Patent ID: 7415837
Filing Date: 2008-08-26
Classification: F24F,F28D,F28F,Y02B

Abstract:
1. Dewpoint cooler, comprising: a first medium circuit and a second medium circuit thermally coupled thereto via an at least partially heat-conducting wall, through which two circuits two respective media can flow in counterflow, wherein at least the second medium contains a gas, for instance air, with a relative humidity of less than 100%; which heat-conducting wall has break-up means for breaking up at least the thermal boundary layer, the laminar boundary layer and the relative humidity boundary layer at the position of at least active zones for heat transfer in at least the primary medium, which break-up means comprise heat-conducting protrusions which enlarge the effective heat-conducting surface area of said wall; wherein the heat-conducting surfaces of said wall and the break-up means are at least partially covered at least in the area of the secondary medium with a hydrophilic, for instance hygroscopic coating, which coating is for instance porous and/or can absorb an evaporable liquid, for instance water, by capillary action, retain it and relinquish it again through evaporation, such that the wetted coating, and thereby also the heat-conducting surfaces and the break-up means, are cooled; primary drive means based on pressure difference, for instance a fan or pump, for the primary medium; secondary drive means based on pressure difference, for instance a fan, for the secondary medium; a wetting unit for subjecting the secondary medium to wetting by the evaporable liquid by evaporating liquid from the coating such that the evaporated liquid entrained by the secondary medium extracts heat from the primary medium via the heat-conducting wall; and wherein the coating consists of a porous technical ceramic material, for instance a burnt layer, a cement such as a Portland cement, or a fibrous material, for instance a mineral wool such as rockwool; and wherein the coefficient of heat transfer of the whole wall amounts to a minimum of 1 W/m