Research impact

Energy saving from improved fuels, engine combustion, and reduced hazards

Research team

Dr M Lawes, Professor D Bradley, Dr A Burluka

Summary

Experimental research and computer modelling in the School of Mechanical Engineering are being applied by engine and oil companies to reduce fuel consumption and noxious emissions. Studies into high pressure explosions and burn rates have helped industry improve engine efficiencies by up to 30% and contributed to the development of much improved fuels. These new products perform better, are less environmentally damaging. and have generated new company revenues. Research into burn-rates, detonations, and large jet-flames has also informed health and safety investigations, particularly the Inquiry into the Buncefield explosion, providing calculations and explanations of the blast, and recommendations on future safety controls.

Research

The team’s internationally-leading research, involves theoretical, experimental, and computer modelling studies, and is directed at: (a) better control of burn rate, (b) high pressure, ‘knock-free’, combustion, (c) general reduction of the risk of large explosions, and (d) control of jet-flames. The underlying theme is that of better understanding of the dynamics and mechanisms of controlled combustion, and uncontrolled explosions. New insights have been widely accepted and applied, resulting in better characterisation of improved new fuels, and better control of combustion, resulting in more efficient engines and turbines. Fundamental work on auto-ignition and knock is proving to be particularly fruitful. Combined with work on laminar and turbulent burning velocities, it suggests better ways of characterising the new fuels than through the use of Octane numbers. The same research is also applied to developing improved safety features to prevent explosions and detonations in large chemical plants, and nuclear installations.

Impact

Advances continue on characterising burn rates of bio-fuels [1,2], and the development of more efficient engines and fuels with Jaguar Land-Rover, Shell, and Ferrari [3]. Fundamental studies of hot spot auto-ignitions have engendered new collaborations with Aachen and Tsinghua Universities [4], and the international Consortium on rapid compression machine practice. Applications to the prevention of major explosion hazards continue with the Shell Major Hazards Group. Research on jet flames, which is relevant to “fracking” flaring practices continues [5], with Dr Palacios working at the State Key laboratory of Fire Science, Heifei obtaining data from high-altitude flares in Tibet.

Publications

[1]. D Bradley, M Lawes, Shiyong Liao, A Saat, “Laminar mass burning and entrainment velocities and flame instabilities of i-octane, ethanol and hydrous ethanol/air aerosols", Combust. Flame 161 (2014) 1620–1632.

[2]. J Vancoillie, G Sharpe, M Lawes, S Verhelst. “The turbulent burning velocity of methanol-air mixtures,” Fuel 130 (2014) 76-91.

[3]. Zhengyang Ling, A Burluka, U Azimov, "Knock properties of oxygenated blends in strongly charged and variable compression ratio engines", SAE Paper 2014-01-2608.

[4]. D. Bradley, L. Bates, N. Peters, “Engine Hot Spots: Decay, Deflagration, Auto-Ignitive Propagation, or Detonation?” submitted to the ICDERS 2005 Colloquium.

[5]. D. Bradley, P.H. Gaskell, X.J. Gu, A. Palacios, “Jet flame size and flame surface density correlations for a n extensive range of fuels and flow rate”, 35th Symposium on Combustion (2014).