Reduced thermal expansion closure bars for a heat exchanger

Abstract

A plate fin heat exchanger is configured to receive hot flow from a hot source and cool flow from a cool source. The plate fin heat exchanger includes a plurality of plates arranged in parallel to define a plurality of flow passages therebetween, and a set of closure bars arranged at a first side of the plurality of plates to seal a first set of the flow passages against ingress of the hot flow, thereby directing the hot flow into a second set of the flow passages. Each respective closure bar includes an inner core formed of a first material having a first coefficient of thermal expansion and an outer cladding arranged about the inner core, the outer cladding formed of a second material having a second coefficient of thermal expansion. The first coefficient of thermal expansion is less than the second coefficient of thermal expansion.

1 . A closure bar for a plate fin heat exchanger, the closure bar comprising:
 a first end and a second end, opposite the first end, defining a first length therebetween;   a first major face and a second major face, opposite the first major face, defining a first thickness therebetween;   a first minor face and a second minor face, opposite the first minor face, defining a first width therebetween;   an inner core formed of a first material having a first coefficient of thermal expansion, the inner core having a second length that is less than the first length and a second width that is greater than half of the first width; and   an outer cladding arranged about the inner core and formed of a second material having a second coefficient of thermal expansion.   
     
     
         2 . The closure bar of  claim 1 ,
 wherein the first coefficient of thermal expansion is less than the second coefficient of thermal expansion.   
     
     
         3 . The closure bar of  claim 1 ,
 wherein the first material comprises titanium; and   wherein the second material comprises aluminum.   
     
     
         4 . The closure bar of  claim 1 ,
 wherein the inner core has a second thickness equal to the first thickness.   
     
     
         5 . The closure bar of  claim 1 ,
 wherein the inner core tapers from the second width toward at least one of the first and second ends of the closure bar.   
     
     
         6 . The closure bar of  claim 1 ,
 wherein the inner core tapers from the second width toward each of the first and second ends of the closure bar.   
     
     
         7 . A closure bar for a plate fin heat exchanger, the closure bar comprising:
 a first end and a second end, opposite the first end;   a first major face and a second major face, opposite the first major face;   a first minor face and a second minor face, opposite the first minor face;   an inner core formed of a first material having a first coefficient of thermal expansion, the inner core tapering from a maximum width of the inner core toward at least one of the first end and the second end of the inner core; and   an outer cladding arranged about the inner core, the outer cladding formed of a second material having a second coefficient of thermal expansion that is greater than the first coefficient of thermal expansion.   
     
     
         8 . The closure bar of  claim 7 ,
 wherein a length of the closure bar between the first end and the second end is greater than a length of the inner core.   
     
     
         9 . The closure bar of  claim 7 ,
 wherein a length of the closure bar between the first end and the second end is equal to a length of the inner core.   
     
     
         10 . The closure bar of  claim 7 ,
 wherein a thickness of the outer cladding is equal to a thickness of the inner core.   
     
     
         11 . The closure bar of  claim 7 ,
 wherein a thickness of the inner core is greater than half of a thickness of the closure bar between the first major face and the second major face.   
     
     
         12 . The closure bar of  claim 7 ,
 wherein the first material comprises titanium; and   wherein the second material comprises aluminum.