Patent ID: 8163047

Claim:
A method of cooling fluid flowing through a chamber, said method comprising: channeling a hot fluid downwardly from a combustion zone to a first passage surrounding the combustion zone, wherein the combustion zone is defined within a refractory wall, and the first passage is defined between the refractory wall and an outer wall spaced radially outwardly from the refractory wall; channeling the hot fluid upwardly through the first passage to a second passage surrounding the first passage; channeling cooling fluid through a plurality of cooling tubes positioned within the first passage, wherein the cooling fluid is channeled into an inlet extending through an outer wall of the chamber, through a plurality of cooling tubes coupled to the inlet, and through an outlet extending through the chamber outer wall, each cooling tube of the plurality of cooling tubes including a first end coupled to the inlet, a second end coupled to the outlet, and an outer surface that extends between the first end and the second end, wherein each cooling tube extends through the first passage such that the plurality of cooling tubes are spaced circumferentially about the combustion zone; circulating the hot fluid flowing within the first passage around each cooling tube using at least one fluid diverter coupled to each cooling tube such that the hot fluid is channeled from the combustion zone across each cooling tube outer surface from the first end towards the second end; and channeling the cooling hot fluid downwardly through the second passage towards an outlet.