Patent ID: 7895823

Claim:
A heat exchanger comprising: an inner hollow liner forming a duct coupled to a rocket engine exhaust system for flow of exhaust gas therethrough, the inner hollow liner having an outer periphery and a plurality of transverse fins disposed in the duct and extending thereacross, each of the fins having a fluid passage therethrough with opposite ends in communication with the outer periphery of the inner hollow liner; an outer jacket joined to the inner hollow liner, the outer jacket having an inlet for entry of a fluid to be heated and an outlet for exit of the fluid to be heated; and a fluid path formed between the inner hollow liner and the outer jacket, the fluid path having a portion extending from the inlet of the outer jacket to an end of the fluid passage in one of the fins, a portion extending from the opposite end of said fluid passage in said one of the fins and from there to an end of the fluid passage in another of the fins, and a portion extending from the opposite end of said fluid passage of said another of the fins to the outlet of the outer jacket, whereby fluid introduced into the inlet of the outer jacket is conveyed between the outer jacket and the inner hollow liner, through each of the fins, and to the outlet of the outer jacket for heating of the fluid.