Fuel cell reformer

An improved multiple-tube catalytic reformer comprising a tubular body containing a radiator core having a plurality of longitudinal cells for low-pressure flow-through of combustion gases, the core being formed preferably either by winding of corrugated metal or as an extruded metal monolith. A plurality of reformer tubes, preferably non-cylindrical, containing hydrocarbon catalyst are arrayed in longitudinal openings within the radiator core and preferably are brazed thereto to maximize heat transfer from the radiator core to the reformer tubes. During manufacture, the metal radiator core is economically bored by laser cutting to form the openings to admit the reformer tubes for brazing. Preferably, the reformer tubes are numbered, sized, shaped, and arrayed to minimize the longest conduction path in the radiator core to the center of any reformer tube.