摘要：Considering the importance of alternative fuels in IC engines for environment safety, compressed natural gas has been
extensively employed in SI engines. However, scarce efforts have been made to investigate the effect of compressed
natural gas on engine lubricant oil for a long duration. In this regard, a comprehensive analysis has been made on the
engine performance, emissions, and lubricant oil conditions using gasoline (G) 92 and compressed natural gas at different
operating conditions using reliable sampling methods. The key parameters of the engine performance like brake power
and brake-specific energy consumption were investigated at 80% throttle opening within 1500–4500 range of r/min. For
the sake of emission tests, speed was varied uniformly by varying the load at a constant throttle. Furthermore, the
engine was run at high and low loads for lubricant oil comparison. Although compressed natural gas showed a decrease
in brake-specific energy consumption (7.94%) and emissions content, (G) 92 performed relatively better in the case of
brake power (39.93% increase). Moreover, a significant improvement was observed for wear debris, lubricant oil
physiochemical characteristics, and additives depletion in the case of compressed natural gas than those of (G) 92 . The
contents of metallic particles were decreased by 23.58%, 36.25%, 42.42%, and 66.67% for iron, aluminum, copper, and
lead, respectively, for compressed natural gas.
