Experimental study on the combustion characteristics of an asymmetric swirling flameless combustor using biogas

ABSTRACT

This work investigated temperature field, temperature uniformity, thermal efficiency, and pollutant emission of an asymmetric swirling combustor operating with different biogas compositions under various configurations to determine the optimum condition for operating and utilizing the combustor. From the results obtained from the combustor, configuration FATB10812 (10 axial air-ports, 8 tangential air-ports, and 12 fuel ports) gave better temperature uniformity, higher efficiency, and lower pollutant emission compared to other configurations due to the broader circumferential injection points in the configuration. Also, 75% methane composition gave a better performance of the combustor due to a moderate level of temperature, which suppresses the formation of both CO and NO_x emissions, even though 90% methane composition gave efficiency, which is slightly higher than 75% with 2%, due to the presence of 25% of incombustible CO₂ in 75% methane composition. Therefore, the optimum condition proposed from this work is configuration FATB10812 operating with biogas of 75% methane composition biogas.

KEYWORDS:

• Flameless combustion
• emission
• swirler
• asymmetric combustor
• pollution

Nomenclature

NOx	=	Oxides of Nitrogen
SCFH	=	Square cubic feet per hour
HiREF	=	High Speed Reacting Flow Laboratory
LPG	=	Liquefied Petroleum Gas
LHV	=	Lower Heating Value

Acknowledgements

The authors would like to extend their appreciation to the government of Nigeria for sponsoring the first author through TETFUND. Also, we are grateful for the financial support of the UTM-High Impact Research Grant Vote Q.J130000.2451.09G05.

Disclosure statement

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

Data availability statement

The data that support the findings of this study are openly available in Mendeley Data at http://doi.org/10.17632/8z5hbnsbvg.1

Additional information

Funding

Financial support was provided by UTM-High Impact Research Grant Vote Q.J130000.2451.09G05.

Notes on contributors

Najib Aminu Ismail

Najib Aminu Ismail is a lecturer in the Department of Mechanical Engineering, Ahmadu Bello University, Zaria. He obtained his PhD and MSc in Mechanical Engineering from Universiti Teknologi Malaysia. His research interest include combustion and renewable energy.

Mazlan Abdul Wahid

Mazlan Abdul Wahid is a Professor of Mechanical Engineering in the Faculty of Mechanical Engineering in Universiti Teknologi Malaysia. He obtained his PhD in Mechanical Engineering from The State University of New York, Buffalo, New York, United State of America, MSc in Mechanical Engineering from University of Leeds, United Kingdom and Bachelor Degree in Aeronautical Engineering from Embry-Riddle Aeronautical University, Daytona Beach, Florida, United State of America. His research areas include combustion, heat transfer and thermodynamics. He has published many articles in reputable journals and conferences.

Aminuddin Sa’at

Aminuddin Sa’at is an Associate Professor in the Department of Thermo-Fluid, Faculty of Mechanical Engineering, Universiti Teknologi Malaysia. He obtained his PhD in Mechanical Engineering from University of Leeds in the United Kingdom and MSc in Automotive Engineering from Coventry University, United Kingdom. He is an expert in combustion and fuels.

Abubakar Shitu

Abubakar Shitu obtained his advanced degree at the Central South University, Changsha, Hunan Province PRC. He is currently with the Department of Aeronautics, Automotive and Ocean Engineering Faculty of Mechanical Engineering, Universiti Teknologi Malaysia (UTM), Johor Bahru, Malaysia. He is an expert in Internal Combustion Engine, Modelling and Simulation, Alternative Fuel and Electric Vehicle. He has published over 40 articles in journals and conferences.

Mohammed Bashir Abdulrahman

Mohammed Bashir Abdulrahman is a Senior Lecturer, Mechanical Engineering, Department Federal Polytechnic, Mubi, Adamawa State Nigeria. Obtained his PhD from Universiti Teknologi Malaysia with specialization in flameless combustion, M.Eng. Energy Engineering at Bayero University Kano, Nigeria, and B.Eng. from University of Maiduguri He is currently working in the area of solar energy and flameless combustion.