Nox emission from a spark ignition engine using 30% iso-butanol-gasoline blend: Part 1 - Preheating inlet air

This research investigated the effect of using a 30% iso-butanol-gasoline blend on NOx emission in a spark ignition engine. The influence of preheating inlet air on NOx emission was also investigated at different fuel/air equivalence ratio. A single cylinder Hydra research engine was used, running at 1500 rpm over a wide range of fuel/air equivalence ratio (0.7-1.1). It was observed that by using the 30% iso-butanol-gasoline blend, the maximum level of NOx emission is reduced by 9% compared to gasoline and the reduction of NOx level was evident in the rich region. The experimental investigations were performed under different values of inlet air temperatures. Preheating the inlet air above ambient temperature causes the NOx emission level to increase for all fuel/air equivalence ratios. At Phi = 0.90, a 10% increase in NOx was observed when the inlet air temperature increased from 40 to 60 degrees C. For 30% iso-butanol-gasoline blend experimental results show that preheating inlet air causes knock and misfire to occur at less advanced ignition timing. (C) 1998 Elsevier Science Ltd. All rights reserved.