BigPatents India

The thermal performance of the heat transfer element assemblies (40) for rotary regenerative air preheaters (10) is optimized to provide a desired level of heat transfer and pressure drop with a reduced volume and weight. The heat transfer plates (44, 46, 48) in the assemblies (50) have notches (50) for maintaining plate spacing and oblique undulations (58) between the notches (50). The undulations (58) on adjacent plates (44, 46, 48) extend at opposite oblique angles. The ratio of the openings of the undulations (58) to the openings of the notches (50) is greater than two inches and the angle of the undulations (58) with respect to the notches (50) is greater than 20° and less than 40° . (FIG. 3)