Patent ID: 7011148

Claim:
A heat exchanger comprising: an air flow structure that has a top surface, a bottom surface, a width, a length, a first edge that runs along the width, a second edge that runs along the width, a plurality of first grooves in the top surface, and a plurality of second grooves in the bottom surface, the first and second grooves extending along the length between the first and second edges; a first wall that contacts substantially all of the first edge of the air flow structure, the first wall having a plurality of openings that extend through the first wall such that each opening is surrounded by the first wall, no portion of the first wall extending into the plurality of first grooves, the first wall preventing a fluid in the first grooves from flowing past the first edge, the plurality of openings allowing a fluid in the second grooves to flow past the first edge; and a second wall that contacts substantially all of the second edge of the air flow structure, the second wall having a plurality of openings that extend through the second wall such that each opening in the second wall is surrounded by the second wall, no portion of the second wall extending into the plurality of first grooves, the second wall preventing a fluid in the second grooves from flowing past the second edge, the plurality of openings in the second wall allowing a fluid in the first grooves to flow past the second edge.