Abstract: Disclosed is a heat transfer assembly for a rotary regenerative preheater. The heat transfer assembly, includes, a plurality of heat transfer elements stacked in spaced relationship to each other in a manner such that each notch from a plurality of notches of one of the heat transfer element rests on respective flat sections from a plurality of flat sections of the adjacent heat transfer elements to configure a plurality of closed channels, each isolated from the other, wherein each of the channels has a configuration in a manner such that each of corrugation sections from a plurality of corrugation sections of one of the heat transfer elements faces respective undulation sections from a plurality of undulation sections of the adjacent heat transfer elements.

Abstract: A closed channel rotary regenerative air preheater includes element supporting baskets that have first heat transfer elements having first arches arranged in an alternating order with second heat transfer elements having second arches. Each of the first arches has a first apex and a concave segment extending therefrom and each of the second arches has a second apex and a convex segment extending therefrom. Each of the convex segments is nested in a respective one of the concave segments thereby defining a contact line therebetween which extends an entire length of the first heat transfer element and the second heat transfer element. Adjacent pairs of the contact lines define a closed passageway therebetween and between the first heat transfer element and the second heat transfer element for heat transfer fluid flow therethrough.

Abstract: A rotary regenerative heat exchanger (1) employs heat transfer elements (100) shaped to include notches (150), which provide spacing between adjacent elements (100), and undulations (corrugations) (165,185) in the sections between the notches 150. The elements (100) described herein include undulations (165,185) that differ in height and/or width.

Abstract: Disclosed is a heat transfer assembly for a rotary regenerative preheater. The heat transfer assembly, includes, a plurality of heat transfer elements stacked in spaced relationship to each other in a manner such that each notch from a plurality of notches of one of the heat transfer element rests on respective flat sections from a plurality of flat sections of the adjacent heat transfer elements to configure a plurality of closed channels, each isolated from the other, wherein each of the channels has a configuration in a manner such that each of corrugation sections from a plurality of corrugation sections of one of the heat transfer elements faces respective undulation sections from a plurality of undulation sections of the adjacent heat transfer elements.

Abstract: Disclosed is a heat transfer assembly for a rotary regenerative preheater. The heat transfer assembly, includes, a plurality of heat transfer elements stacked in spaced relationship to each other in a manner such that each notch from a plurality of notches of one of the heat transfer element rests on respective flat sections from a plurality of flat sections of the adjacent heat transfer elements to configure a plurality of closed channels, each isolated from the other, wherein each of the channels has a configuration in a manner such that each of corrugation sections from a plurality of corrugation sections of one of the heat transfer elements faces respective undulation sections from a plurality of undulation sections of the adjacent heat transfer elements.

Abstract: A closed channel rotary regenerative air preheater 110 employs differing heat transfer elements 186, 196, arranged in an alternating order to impart turbulence in fluid flowing in closed channels or passageways 164 between the heat transfer elements 186, 196, to maintain heat transfer properties with reduced pressure drop.

Abstract: A rotary regenerative heat exchanger [1] employs heat transfer elements [100] shaped to include notches [150], which provide spacing between adjacent elements [100], and undulations (corrugations) [165,185] in the sections between the notches 150. The elements [100] described herein include undulations [165,185] that differ in height and/or width. These impart turbulence in the air or flue gas flowing between the elements [100] to improve heat transfer.

Abstract: Disclosed is a heat transfer assembly for a rotary regenerative preheater. The heat transfer assembly, includes, a plurality of heat transfer elements stacked in spaced relationship to each other in a manner such that each notch from a plurality of notches of one of the heat transfer element rests on respective flat sections from a plurality of flat sections of the adjacent heat transfer elements to configure a plurality of closed channels, each isolated from the other, wherein each of the channels has a configuration in a manner such that each of corrugation sections from a plurality of corrugation sections of one of the heat transfer elements faces respective undulation sections from a plurality of undulation sections of the adjacent heat transfer elements.

Abstract: A rotary regenerative heat exchanger (1) employing heat transfer elements (100) is shaped to include notches (150), providing spacing between adjacent elements (100) and undulations (corrugations) (165, 185) in sections between the notches (150). Elements (100) include undulations (165, 185) differing in height and/or width. These differing undulations impart turbulence to air or flue gas flowing between the elements (100) for heat transfer thereto.

Abstract: A rotary regenerative heat exchanger [1] employs heat transfer elements [100] shaped to include notches [150], which provide spacing between adjacent elements [100], and undulations (corrugations) [165,185] in the sections between the notches 150. The elements [100] described herein include undulations [165,185] that differ in height and/or width. These impart turbulence in the air or flue gas flowing between the elements [100] to improve heat transfer.

Abstract: The flue gas temperature coming from an air preheater to a particulate collection device such as an electrostatic precipitation or fabric filter is reduced to improve the operation of the particulate collection device. This may be done by reducing the exit flue gas temperature from the air preheater or reducing the temperature after exiting. In one embodiment, air in excess of that needed for combustion is passed through the air preheater with the heated excess air either being dumped or used for a variety of purposes in the plant. A particular embodiment involves segmenting the air outlet side of a rotary regenerative air preheater and withdrawing the excess air from the segment where the dust loading is the lowest. Further, additional cooling of the flue gas can be provided by reducing the quantity of primary air that typically bypasses the air preheater and then providing other ways to control the primary air temperature to the pulverizers.

Abstract: Heat transfer elements for rotary regenerative heat exchangers are formed with spacing ridges or notches having flow-disrupting indentations in the peaks of the notches formed at selected intervals to project into the flow channels. These projections interrupt the boundary layer and cause turbulence and mixing to enhance the heat transfer. Various methods of forming the indentations are disclosed.

Abstract: Heat transfer elements for rotary regenerative heat exchangers are formed with spacing ridges or notches having flow-disrupting indentations in the peaks of the notches formed at selected intervals to project into the flow channels. These projections interrupt the boundary layer and cause turbulence and mixing to enhance the heat transfer. Various methods of forming the indentations are disclosed.

Abstract: A heat exchange element for an air preheater has first and second heat transfer elements arranged to form channels for the passage of a heat exchange media having a main flow direction. Each of the heat exchange plates has parallel straight ridges and flats between the ridges. The ridges alternate to extend transversely from opposite sides of each heat transfer plate. The ridges of the adjacent plates are oriented obliquely in opposite directions relative to the main flow direction and contact each other solely at points of intersection of the ridges.