Transactions of the Korean hydrogen and new energy society (한국수소및신에너지학회논문집)

The Korean Hydrogen and New Energy Society (한국수소및신에너지학회)
권호 표지

Studies on a Micro Reformer System with a Two-staged Microcombustor

초소형 2단 연소기를 이용한 리포머 시스템에 관한 연구

  • Published : 2008.06.30
Download PDF
⟨ Previous Next ⟩

Abstract

A new micro reformer system consisted of a micro reformer, a microcombustor and a micro evaporator was studied experimentally and computationally. In order to satisfy the primary requirements for designing the microcombustor integrated with a micro evaporator, i.e. stable burning in a small confinement and maximum heat transfer through a wall, the present microcombustor is simply cylindrical to be easily fabricated but two-staged (expanding downstream) to feasibly control ignition and stable burning. Results show that the aspect ratio and wall thickness of the microcombustor substantially affect ignition and thermal characteristics. For the optimized design conditions, a premixed microflame was easily ignited in the expanded second stage combustor, moved into the smaller first stage combustor, and finally stabilized therein. A micro reformer system integrated with a modified microcombustor based on the optimized design condition was fabricated. For a typical operating condition, the designed micro reformer system produced 22.3 sccm hydrogen (3.61 W in LHV) in an overall efficiency of 12%.

Keywords

References

  1. Lu G. Q., and Wang C. Y., 'Development of micro direct methanol fuel cells for high power applications,' J. Power Sources, Vol. 144, 2005, pp. 141-145 https://doi.org/10.1016/j.jpowsour.2004.12.023
  2. Shioya M., 'Expectation of micro fuel cell technology,' 2nd Int. Hydrogen & Fuel Cell Expo, Tokyo, Japan, 2006, pp. 69-85
  3. Shin Y., Kim O., Hong J.-C., Oh J.-H., Kim W.-J., Haam S., and Chung C.-H., 'The development of micro-fuel processor using low temperature co-fired ceramic(LTCC)', Int. J. Hydrogen Energy., Vol. 31, 2006, pp. 1925-1933 https://doi.org/10.1016/j.ijhydene.2006.02.028
  4. Yoshida K., Tanaka S., Hiraki H., and Esashi M., 'A micro fuel reformer integrated with a combustor and a microchannel evaporator,' J. Micromech. Microeng., Vol. 16, 2006, pp. 191-197 https://doi.org/10.1088/0960-1317/16/2/001
  5. Fluent Inc., 'Fluent 6.2 User's Guide,' Fluent Inc., Lebanon, NH, USA., 2005
  6. Kee R. J., Rupley F. M., and Miller J. A., 'The CHEMKIN Thermodynamic Data Base,' Report No. SAND87-8215B, Sandia National Laboratories, Albuquerque, NM, USA., 1992
  7. Hautman D. J., Dryer F. L., Schug K. P., and Glassman I., 'A multiple-step overall kinetic mechanism for the oxidation of hydrocarbons,' Combust. Sci. Tech., Vol. 25, 1981, pp. 219-235 https://doi.org/10.1080/00102208108547504
  8. Peckner D., and Bernstein I. M., 'Handbook of Stainless Steels,' McGraw-Hill, New York, NY, USA. 1987, pp. 19.1-19.36
  9. Kim K. B., and Kwon O. C., 'Studies on a two-staged micro-combustor for a micro-reformer integrated with a micro-evaporator,' J. Power Sources, Vol. 182, 2008, pp. 609-615 https://doi.org/10.1016/j.jpowsour.2008.04.053
  10. Pina J., Bucalá V., and Borio D.O., 'Optimization of steam reformers: Heat flux distribution and carbon formation,' Int. J. Chem. Reactor Eng. Vol. 1, 2003, p. A25
  11. Tonkovich A.Y., Zilka J.L., Jimenez D.M., Lamont M.J., and Wegeng R.S., 'Microchannel Chemical Reactors for Fuel Processing', AIChE Spring National Meeting, New Orleans, USA, March 9-12, PNNL-SA-29747, 1998