265662 Studies On a Micro-Thermophotovoltaic Device with a H2-NH3-Fueled Micro-Emitter

Thursday, November 1, 2012: 4:55 PM
322 (Convention Center )
Sang Ik Lee1, Hu Wu2, Dong Hyun Um2 and Oh Chae Kwon2, (1)Hyundai Dymos Inc., Hwaseong, South Korea, (2)School of Mechanical Engineering, Sungkyunkwan University, Suwon, South Korea

The potential of hydrogen (H2)-ammonia (NH3) blends as a carbon-free, green fuel in a 1–10 W micro-thermophotovoltaic (micro-TPV) device is evaluated experimentally. When H2-NH3 blends are used directly (without any modification) in a micro-TPV configuration that was developed for hydrocarbon fuel, applying a heat-recirculation concept and having an installation of gallium antimonide photovoltaic cells, low temperature on the micro-emitter outer surface are observed, generating a secondary flame at the micro-emitter outlet. To remove the secondary flame, satisfying the primary requirements for designing the micro-emitter (stable burning in the small confinement and uniform and high temperature along the walls), cyclone and helical adapters are installed at the fuel-air mixture inlet and upstream the main combustion zone, respectively. Also, the micro-emitter is extended to enhance the heat-recirculation effects. The helical adaptor with a large helix angle yields better performance, increasing the micro-emitter temperature. Under optimized design and operating conditions, the micro-TPV device produces 5.2 W with an overall efficiency of 0.87% and an emitter efficiency of 14%, indicating the maximum temperature of the micro-emitter outer surface up to 1408 K. Thus, the feasibility of H2-NH3 blends in practical micro power-generation devices has been demonstrated, implying the potential of partial NH3 substitution to improve the safety of H2 use with no carbon generation.

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See more of this Session: Alternative Fuels and Enabling Technologies III
See more of this Group/Topical: Fuels and Petrochemicals Division