An Ammonia/Hydrogen-Fueled Micro-Thermophotovoltaic Device Integrated with a Micro-reformer

摘要

The potential of ammonia (NH_3)-hydrogen (H_2) blends as a carbon-free fuel in a micro-thermophotovoltaic (micro-TPV) device integrated with a micro-reformer is evaluated experimentally. A micro-emitter as a thermal heat source is a simple cylinder with an annular-type shield to adopt a heat-recirculation concept and an expanded exhaust outlet to control ignition, which provides stable burning in a small confinement and uniform distribution of temperature along the outer wall. The micro-emitter is surrounded with a micro-reformer for converting NH_3 to H_2 using ruthenium as a catalyst. The micro-reformer is surrounded by a chamber, the inner and outer walls of which have installations of gallium antimonide (GaSb) photovoltaic cells and cooling fins, respectively. Under optimized design and operating conditions, the micro-TPV device integrated with the micro-reformer shows the emitter efficiency up to 37 % with the maximum temperature of the micro-emitter outer surface up to 1468 K and the conversion rate of NH_3 to H_2 up to 96.0% in the micro-reformer. Thus, the feasibility of using NH_3H_2 blends in practical micro power and H_2 generation devices has been demonstrated, implying the potential of partial NH_3 substitution to improve the safety of pure H_2 use with no carbon generation.