Counter-flow energy recovery ventilator (erv) core

Abstract

A heat and humidity exchanger has example application in exchanging heat and water vapor between fresh air entering a building and air being vented from the building. The heat and humidity exchanger has a self-supporting core formed from layered sheets of a moisture-permeable material. Plenums are arranged to direct fluid streams into and out of the core. The plenums may be on opposing sides of the core to permit counterflow exchange of heat and water vapor.

What is claimed is: 
     
         1 . A heat and humidity exchanger core comprising:
 a plurality of water vapor-permeable layers stacked and joined together;   at least some of the water vapor-permeable layers comprising molded sheets, the molded sheets comprising a sheet of a composite material comprising a porous formable support layer and an air-impermeable and water-vapor-permeable coating supported by the support layer wherein the sheet of composite material is formed to include out-of-plane features, the molded sheet having a central section and first and second manifold regions, the out-of-plane features in the central section configured to, together with adjacent ones of the layers of the core, define a first plurality of channels extending between the first and second manifold regions on a first face of the molded sheet and a second plurality of channels extending between the first and second manifold regions on a second first face of the molded sheet opposed to the first face when the molded sheet is stacked between the adjacent ones of the layers of the core, the channels of the first and second pluralities of channels having heights of at least 2 mm, the heights of the plurality of channels determined at least in part by dimensions of the out-of-plane features of the central section,   an inlet plenum and an outlet plenum between each adjacent pair of the stacked layers, the inlet plenum defined at least in part by the first manifold region of one of the stacked molded sheets, and the outlet plenum defined at least in part by the second manifold region of the one of the stacked molded sheets, the plurality of channels fluidly connecting the inlet plenum to the outlet plenum, the manifold regions configured such that the inlet and outlet plenums each fluidly connect the first plurality of channels, the inlet plenum is arranged to direct a first flow into the plurality of channels at one side of the central section and the outlet plenum is arranged to receive the first flow on the other side of the central section.   
     
     
         2 . The heat and humidity exchanger core of  claim 1  wherein the molded sheets are hexagonal, the central section of each molded sheet is rectangular and extends between opposing edges of the hexagonal sheet, and the first and second manifold regions of each molded sheet are triangular. 
     
     
         3 . The heat and humidity exchanger core of  claim 1  wherein each of the plurality of water vapor-permeable layers comprises one of the molded sheets. 
     
     
         4 . The heat and humidity exchanger core of  claim 3  wherein each of the plurality of channels is defined between the central sections of an adjacent pair of the stacked molded sheets and each of the plurality of channels is quadrilateral in cross-section. 
     
     
         5 . The heat and humidity exchanger core of  claim 3  wherein each of the plurality of channels defined by the central sections of adjacent pairs of stacked molded sheets is rectangular in cross-section and the channels have widths of at least 2 mm. 
     
     
         6 . The heat and humidity exchanger core of  claim 1  wherein the molded sheets make up alternate ones of the stacked layers and flat water-vapor-permeable sheets make up alternate ones of the stacked layers. 
     
     
         7 . The heat and humidity exchanger core of  claim 6  wherein each of the plurality of channels is defined between the central section of one of the molded sheets and a flat surface of one of the flat sheets and the channels of the plurality of channels are triangular in cross-section. 
     
     
         8 . The heat and humidity exchanger core of  claim 6  wherein the flat sheets are made from the same material as the molded water vapor-permeable sheets. 
     
     
         9 . The heat and humidity exchanger core of  claim 1  wherein the support layer of the molded water vapor-permeable sheets comprises a non-woven fabric and the molded water vapor-permeable sheets comprise a nanofibrous layer on the nonwoven fabric. 
     
     
         10 . The heat and humidity exchanger core of  claim 1  wherein the molded sheets are formed to provide out-of-plane features in the first and second manifold regions. 
     
     
         11 . The heat and humidity exchanger core of  claim 10  wherein the out-of-plane features in each of the first and second manifold regions comprise walls defining a periphery of a corresponding one of the plenums. 
     
     
         12 . The heat and humidity exchanger core of  claim 10  wherein the out-of-plane features in the first and second manifold regions comprise a plurality of ribs formed in each of the first and second manifold regions. 
     
     
         13 . The heat and humidity exchanger core of  claim 1  wherein the core is potted with a sealant material on at least two faces of the core, whereby adjacent ones of the stacked layers are joined together by the sealant material. 
     
     
         14 . The heat and humidity exchanger core of  claim 1  wherein the molded sheets are stamped. 
     
     
         15 . The heat and humidity exchanger core of  claim 1  wherein the central sections of the molded sheets are formed to provide parallel corrugations.