Investigations on a Spark Ignition Engine, Part I: Fuelled With Biogas Extracted From Sewage

Abstract

In this study, experiments were conducted on a single-cylinder, four-stroke modified diesel engine into a spark ignition engine using biogas from sewage sludge as fuel. The engine was operated at 1500 revolutions per minute at a compression ratio of 13:1. The throttle was set to 25% and 100% to operate the engine at various equivalence ratios to study the combustion, performance, and emissions. At various equivalence ratios and throttle openings, the effects of cycle-by-cycle variation were studied and compared. The brake thermal efficiency and brake power reached their highest values at an equivalence ratio of 0.95 and 1.01 respectively. At these equivalence ratios, carbon monoxide and hydrocarbon emissions were minimal but nitric oxide levels were high. When the mixture becomes lean, the coefficient of variation of the mean effective pressure increases considerably on both throttles. When the engine is running in steady conditions far from the lean limit, the cycle-by-cycle variation is stochastic in nature. Prior cycle impacts and cycle-by-cycle variation occur when the engine is running lean, and they are deterministic. Part II of this study represents the effect of hydrogen addition and change in compression ratio in the performance of spark ignition engines fueled with biogas.

Acknowledgements

The authors wish to thank Vellore Institute of Technology, Vellore for the financial support extended in carrying out this project.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Notes on contributors

Charles Benjamin Essuman

Charles Benjamin Essuman received his PhD in the School of Mechanical Engineering at Vellore Institute of Technology, Vellore, India. He received his M.Tech. in Automotive Engineering at the University of Education, Winneba. Kumasi Campus, Ghana. His main research activities are focused on the use of biogas and hydrogen in spark ignition engines.

Ekambaram Porpatham

Ekambaram Porpatham has been a Professor at the Automotive Research Center, School of Mechanical Engineering at Vellore Institute of Technology, Vellore, India, since 2011. He received his PhD at the Indian Institute of Technology-Madras. His main research activities are focused on the waste-to-energy conversion and use of gaseous fuels in spark ignition engines.