Review of Research on the Application of CNG Fuel in Vehicle Engines: Research Bibliography 2017–2021

Compressed Natural Gas (CNG) is an alternative fuel used to solve cleaner exhaust emissions, global warming, and limited world fossil oil production problems. It emits cleaner gases during combustion, is economical, can be applied to light/heavy vehicles, and has good adaptability to diesel/petrol engines. This research reviews the application of CNG in vehicle engine articles published from 2017 to 2021. There were 82 articles on CNG, while 38 were on CNG as vehicle fuel. The articles reviewed were classified in several focus areas of research, such as the development of the ignition system on the CNG engine, the injection method, the application of Exhaust Gas Recirculating (EGR) technology, variations in the compression ratio of the CNG engine combustion chamber, the application of Reactivity Controlled Compression Ignition Engine (RCCI) on CNG machine, system modeling, mixer and method. The results showed a lack of research on the development of CNG that integrates intelligent control systems. Therefore, further research is suggested to explore the potential effect of the next period.