Studies on the Mint Oil and its Application to Spark Ignition Engine (Part 2)

Air-Fuel Ratio, Ignition Timing and Exhaust NOx Emission

Abstract

The purpose of the present study is focused on determining the proper mixture ratio of blended fuels and proper ignition timing, when a small ignition engine for farm use is operated with 20% by volume peppermint oil blended gasoline and 20% by volume spearmint oil blended gasoline, respectively. It has been confirmed that regarding BSFC as important equivalent ratio is desired 0.9, and regarding BHP as important equivalece ratio is 1.1. It was observed that an appropriate ignition timing were at BTDC 20° CA. This ignition timing showed little difference from originally set value of the engine. For the spark ignition timing it can be seen that conventional ignition system used for commercial ones are well matched to these two fuels. It was also found that on BSFC these 3 tested fuels including neat regular gasoline with lead free agreed very much. However, BMEP for P20 and for S20 are 5.7% and 3.7%, respectively, and it was increased than that of G100. This was also observed from NOx emission obtained to operate the engine with these 3 tested fuels under MBT operating condition.