Patent ID: 6840313

Claim:
A plate fin heat exchanger for high temperature comprising a plurality of core assembly elements, each said core assembly element including first and second tube plates, low-temperature fins disposed between the first and second tube plates for defining low-temperature fluid channels, the low-temperature fins being unaffixed to the first tube plate, an inlet and an outlet to the low-temperature fluid channels being defined on a first side of the core assembly element, spacers disposed between the tube plates, said spacers being secured to both the first and second tube plates along the first side of the core assembly element, all other of said spacers being unaffixed to at least one of said tube plates so that said tube plates are cantilevered from the spacer along the first side of the core assembly element, each said core assembly element further comprising at least one array of high temperature fins secured to at least one of said first and second tube plates on a side thereof opposite the low-temperature fluid channels, the core assembly elements being disposed in a stacked array so that high-temperature fluid channels are defined between adjacent core assembly elements in the stacked array and so that the high temperature fins are in the high-temperature fluid channels, the high-temperature fins being unaffixed to the adjacent core assembly element in the stack array, whereby the cantilevered extension of the tube plates from the spacer at the first side avoids of thermal stress.