本研究使用商用流體力學軟體Fluent 6.3.26進行模擬分析一自熱式甲醇噴霧重組器，目的在於利用噴霧之特性，使重組反應快速啟動，並且於重組器內置入火星塞點燃甲醇噴霧，使觸媒溫度能快速提高至重組反應所需要之溫度。研究中探討甲醇噴霧接觸到觸媒層之模式，當使用Trap作為碰撞觸媒的模式時能正確模擬物理性質。接著針對甲醇自熱式重組器的冷啟動暫態比對，由結果顯示當反應至280秒時，反應達穩態，且出口產物與實驗結果一致。再來調整側邊入口的甲醇量，發現在適當的甲醇流率下，能夠使觸媒溫度在最短時間內達到所需的反應溫度；而當噴霧入口的壓力提高時，也可將產氫達穩態的時間提前，產氫量也會上升。而文獻多使用氣態進入，需費時10分鐘以上。故使用噴霧結合火星塞點火，可有效縮短甲醇重組器之冷啟動時間

The cold start of an autothermal reformer using methanol sprays combined with spark ignition is simulated by using the commercial CFD software FLUENT. A spark plug is used in the reformer to ignite the spray of methanol. In the present study, we used four effects of different modes of the methanol spray touching on the catalyst, and we found that trap mode can describe certainly of the physical phenomena. The most appropriate mode is thus selected. The unsteady autothermal reforming is tested in the next step. By the simulation, it is found that when the time reached 280 seconds, the reforming is going to be steady state. Then we adjust the flow rate of the methanol at the side inlet and the pressure of spray nozzle inlet to optimize the cold start. The numerical results show that the cold start efficiency of an autothermal reformer can be improved by increasing the pressure of spray inlet, and there is an appropriate flow rate of methanol can let catalyst temperature reach the require temperature in the shortest time. Since using the methanol vapor to start the reformer may take more than 10 minutes, using the methanol spray combined with the spark ignition is able to reduce the start-up time significantly.

【1】 Hohlein, B., Boe, M., Bogild-Hansen, J., Brockerhoff, P., Colsman, G., and Emonts, B., “Hydrogen from methanol for fuel cells in mobile systems: development of a compact reformer,” Jouranl of Power Sources, Vol. 61, pp.143-147, 1996.
【2】 Emonts, B., Hansen, J.B., Schmidt, H., Grude, T., Hohlein, B. and Peters, R., “Fuel cell drive system with hydrogen in test,” Journal of Power Sourses, Vol. 86, pp. 228-236, 2000.
【3】 Emonts, B., Hansen, J.B., Jorgensen, S.L., Hohlein, B and Peters, R., “Compact methanol reformer test for fuel-cell-powered light-duty vehicles,” Journal of Power Sources, Vol. 71, pp.288-293, 1998.
【4】 宋隆裕，“燃料電池用甲醇重組器之測試研究”，能源季刊，第二十四卷，第一期，pp.69-88，1993。
【5】 Han, J., S., Kim, I., S., and Choi, K., S., “Purifier-integrate methanol reformer for fuel cell vehicles,” Journal of Power Sources, Vol. 86, pp. 223-227, 2000.
【6】 Peters, R., Dusterward, H.G. and Hohlein, B., “Investigation of a methanol reformer concept considering the particular impact of dynamics and long-term stability for use in a fuel-cell-powered passenger car,” Journal of Power Sources, Vol. 86, pp.507-514, 2000.
【7】 Choi, Y. and Stenger, H.G., “Fuel cell grade hydrogen from methanol on a commercial Cu/Zn/Al2O3 catalyst,” Applied Catalysis B: Environmental, Vol. 38, pp.259-269, 2002.
【8】 Wiese, W., Emonts, B., and Peters, R., “Methanol steam reforming in a fuel cell drive system,” Journal of Power Sources, Vol. 84, pp.187-193, 1999.
【9】 Fu, C. H., and Wu, J. C. S., “Mathematical simulation of hydrogen production via methanol steam reforming using double-jacketed membrane reactor,” International Journal of Hydrogen Energy, Vol. 32, pp. 4830-4839, 2007.
【10】 Liu, N., Yuan, Z., Wang, C., Pan, L., Wang, S., Li, S., Li, D., and Wang, S., “Bench-scale methanol autothermal reformer for distributed hydrogen production,” Chemical Engineering Journal, Vol. 139, pp. 56-62, 2008.
【11】 Suh, J., Lee, M., Greif, R., and Grigoropoulos, C. P., “A study of steam methanol reforming in a microreactor,” Journal of Power Sources, Vol. 173, pp. 458-466, 2007.
【12】 Wang, S., and Wang, S., “Thermodynamic equilibrium composition analysis of methanol autothermal reforming for PEMFC based on FLUENT Software,” Journal of Power Sources, Vol. 185, pp. 451-458, 2008.
【13】 Sattereld, C. N., “Heterogeneous catalysis in industrial practice,” New York, McGraw-Hill Inc., 1991
【14】 Yong, S. T., Hidajat, K., and Kawi, S., “Reaction study of auto thermal steam reforming of methanol to hydrogen using a novel nano CuZnAl-catalyst,” Journal of Power Sources, Vol. 131, pp.91-95, 2004.
【15】 Specchia, S., Galletti, C., Fiorot, S., Saracco, G., and Specchia, V., “CO preferential oxidation over Rh-supported catalyst in H2-rich gas for fuel cell applications,” Fuel Cell Seminar, Vol. 5, pp.677-685, 2006.
【16】 Dupont, N., Germani, G., Veen, A. C. V., Schuurman, Y., Schafer, G.., and Mirodatos, C., “Specificities of micro-structured reactors for hydrogen production andpurification,” International Journal of Hydrogen Energy, Vol. 32, pp. 1443–1449, 2007.
【17】 Kawamura, Y., Ogura, N., Yamamoto, T., and Igarashi, A., “A miniaturized methanol reformer with Si-based microreactor for a small PEMFC,” Chemical Engineering Science, Vol. 61, pp. 1092-1101, 2006.
【18】 Lee, S., Ahmed, S., and Ahluwalia, R., “Steam reforming of ethanol at elevated pressure for hydrogen production,” Fuel Cell Seminar, 2006.
【19】 Moon, D., Ryu, J., Choi, E., Lee, Y., Yoo, K., and Lee, S., “Studies on the development of high performance WGS catalyst for fuel processor applications,” Fuel Cell Seminar, 2006.
【20】 Pino, L., Vita, A., Cipitì, F., Laganà, M., and Recupero, V., “Comparative analysis of catalysts for CO preferential oxidation,” Fuel Cell Seminar, 2006.
【21】 Horng, R. F., Chen, C. R., Wu, T. S., and Chan, C. H., “Cold start response of a small methanol reformer by partial oxidation reforming of hydrogen for fuel cell,” Applied Thermal Engineering, Vol. 26, pp. 1115-1124, 2006.
【22】 Peppley, B.A., Amphlett, J.C., Kearns, L.M., Mann, R.F., “Methanol-steam reforming on Cu/ZnO/Al2O3 catalyst: Part1: the reaction network,” Applied Catalyst A: Genernal (1-2), 21-29, 1999b.
【23】 Peppley, B.A., Amphlett, J.C., Kearns, L.M., Mann, R.F., “Methanol-steam reforming on Cu/ZnO/Al2O3 catalyst: Part 2: A comprehensive kinetic model,” Applied Catalyst A: General 179(1-2), 31-49
【24】 Fukahori, S., Kitaoka, T., Tomoda, A., Suzuki, R., and Wariishi, H., “Methanol steam reforming over paper-like composites of Cu/ZnO catalyst and ceramic fiber,” Applied Catalysis A: General, Vol. 300, pp. 155–161, 2006.
【25】 Koga, H., Fukahori, S., Kitaoka, T., Tomoda, A., Suzuki, R., and Wariishi, H., “Autothermal reforming of methanol using paper-like Cu/ZnO catalyst composites prepared by a papermaking technique,” Applied Catalysis A: General, Vol. 309, pp263–269, 2006.
【26】 Fukahori, S., Koga, H., Kitaoka, T., Tomoda, A., Suzuki, R., and Wariishi, H., “Hydrogen production from methanol using a SiC fibercontaining paper composite impregnated with Cu/ZnO catalyst,” Applied Catalysis A: General, Vol. 310, pp. 138–144, 2006.
【27】 Koga, H., Fukahori, S., Kitaoka, T., Mitsuyoshi, N., and Wariishi, H., “Paper-structured catalyst with porous fiber-network microstructure for autothermal hydrogen production,” Chemical Engineering Journal, Vol. 139, pp. 408-415, 2008.
【28】 Fukahori, S., Koga, H., Kitaoka, T., Nakamura, M., and Wariishi, H., “Steam reforming behavior of methanol using paper-structured catalysts: Experimental and computational fluid dynamic analysis,” International Journal of Hydrogen Energy, Vol. 33, pp. 1661-1670, 2008.
【29】 Choi, K.S., Kim, H.M., Yoon, H.C., “Equilibrium model validation through the experiments of methanol autothermal reformation.” International Journal of Hydrogen Energy, Vol. 33, pp. 7039-7047, 2008.
【30】 Chuang, C. C., Chen, Y. H., Ward, J. D., Yu, C. C., Liu, Y.C., and Lee, C. H., “Optimal design of an experimental methanol fuel reformer,” International Journal of Hydrogen Eneragy, Vol. 33, pp. 7062-7073, 2008.
【31】 Nilsson, M., Karatzas, X., Lindstrom, B., and Pettersson, L. J., “Assessing the adaptability to varying fuel supply of an autothermal reformer,” Chemical Engineering Journal, Vol. 142, pp. 309–317, 2008.
【32】 Ahmet K. Avcı, Z. lsen Önsan, David L. Trimm, “On-board fuel conversion for hydrogen fuel cells: comparison of different fuels by computer simulations”, Applied Catalysis A: General, Vol. 216, pp. 243-256, 2001.
【33】 Metghalchi, M., and Keck, J. C., “Burning velocities of mixtures of air with methanol, isooctane and indolene at high pressures and temperatures,” Combustion and Flame, Vol. 48, pp. 191-210, 1982.
【34】 Fluent 6.3 User’s Guide, 2006.