Single-cylinder 125 CC stepped piston engine for mobility and portable power generation applications

Abstract

Two-stroke engines is far simpler than four-stroke version from its physical perspective. For a given brake output, two-stroke is lighter, easier to work on, and provide higher power-to-weight ratio than the four-stroke, making it suitable for small platform applications. However a conventional two-stroke engine has a reputation for generating smoke and unburned fuel, a situation which does not meet many emissions regulations, now enforced around the world. Thus for many decades two-stroke engines were not favored, giving ways to four-stroke engines to dominate applications, especially for mobile power-generation purposes. In the quest to improve the potential of such an engine, a group of researchers from the Automotive Development Centre (ADC), Universiti Teknologi Malaysia (UTM) has come up with a 125 cc, air-cooled stepped-piston engine to demonstrate the higher power-to-weight ratio feature, apart from overcoming emission reduction. The engine is designed to mitigate the problem of mixture short circuiting, which is the major hindrance to combustion efficiency, and for this to happen they have incorporated a three-port stratification strategy onto the engine. This paper provides the overview related to the earlier work done to infuse the necessary features and highlights some of the performance features of this unique engine design.