Compressed natural gas as an alternative fuel in diesel engines

Abstract

This project investigates the engine performance and exhaust emission of dual-fuel operation on a single cylinder compression ignition engine. Natural gas is used as the main gaseous fuel with diesel as the pilot fuel to provide a source of ignition. The high compression ratios of diesel engines can be achieved without loss in power together with substantial cost reduction in fuel and conversion kits. Comparative results of dual-fuel operation with conventional diesel fuel through experimental results demonstrated its benefits both in the fields of performance and emission. The engine torque and brake power output show vast improvement and dual-fuel operation is able to achieve a higher thermal efficiency under all operating conditions. The emission levels of polluting gases such as carbon monoxide, oxides of nitrogen (NOx) and carbon dioxide also records an enormous decrease.