Abstract: An indirect evaporative cooler core is manufactured from a continuous sheet of hydrophobic material. Flocking is provided on at least a partial surface area of at least one side of the sheet, to render the flocked surface area wettable. Air flow guiding structures are formed upon at least one of the first side and the second side of the sheet. Fold lines are defined in the sheet defining plates extending between adjacent fold lines. Slits are formed along the fold lines. Accordion pleating the sheet at the fold lines forms alternating wet and dry passages between the plates, the wet passages formed between opposing wettable surfaces, the dry passages formed between non-flocked surfaces, and the accordion pleating causes the slits in the folds to open and form air inlets and outlets in communication with the air flow passages.

Abstract: An indirect evaporative cooling system with a core greatly reduced in size compared to conventional evaporative cooling systems The system has a heat exchanger core having heat exchange plates defining a plurality of wet air flow passages and a plurality of dry air flow passages. At least one fan drives air through the passages. The dry air passages have a small height and a short length, configured so that a substantially laminar airflow having a raised shear rate arises in the dry air passages, and so that a back pressure across a length of the dry air passages remains low.

Abstract: An indirect evaporative cooler core is manufactured from a continuous sheet of hydrophobic material. Flocking is provided on at least a partial surface area of at least one side of the sheet, to render the flocked surface area wettable. Air flow guiding structures are formed upon at least one of the first side and the second side of the sheet. Fold lines are defined in the sheet defining plates extending between adjacent fold lines. Slits are formed along the fold lines. Accordion pleating the sheet at the fold lines forms alternating wet and dry passages between the plates, the wet passages formed between opposing wettable surfaces, the dry passages formed between non-flocked surfaces, and the accordion pleating causes the slits in the folds to open and form air inlets and outlets in communication with the air flow passages.

Abstract: An indirect evaporative cooling system with a core greatly reduced in size compared to conventional evaporative cooling systems The system has a heat exchanger core having heat exchange plates defining a plurality of wet air flow passages and a plurality of dry air flow passages. At least one fan drives air through the passages. The dry air passages have a small height and a short length, configured so that a substantially laminar airflow having a raised shear rate arises in the dry air passages, and so that a back pressure across a length of the dry air passages remains low.