Hydrogen-enriched hydrocarbon fuels are widely used in internal combustion engines, and exhaust gas recirculation is one of the most effective ways to decrease NOx emission from internal combustion engines. In order to investigate the effect of CO2 in exhaust gas on combustion characteristics of hydrocarbon fuels with hydrogen addition, the laminar combustion characteristics of hydrogen-air-CO2 mixtures are studied at different equivalence ratios (φ=0.6-1.4) and different CO2 diluent ratios (0%-40%). The results indicated that both flame propagation speed and the Markstein length of hydrogen-air mixtures increases with the increase of equivalence ratio. By increasing diluent ratio, the unstretched flame propagation speed Sl decreases obviously. The effects of diluent gas on flame stability are also discussed in this paper. A polynomial fit to the data from experiments is also obtained, which can be used to calculate the unstretched laminar burning velocity of hydrogen-air-CO2 mixture.
|Number of pages
|Ranshao Kexue Yu Jishu/Journal of Combustion Science and Technology
|Published - 1 Aug 2009