John Griffiths

KEYWORDS combustion chemistry explosion hazards autoignition spontaneous ignition engine knock Kinetic uncertainty analysis

RESEARCH INTERESTS

The major activity is concerned with the gas-phase combustion of hydrocarbons (cool flames and multiple stage ignitions), which is related both to combustion hazards which may arise from spontaneous ignition processes in the chemical industry and to the efficiency of reciprocating engines(the ignition process in diesel engines and the knock problem in spark ignition engines). The gap between the experimental measurements and theoretical interpretations of spontaneous ignition phenomena is bridged by numerical modelling studies, including the assessment of errors in the simulations arising from uncertainties in the paramater values for chemical reactions.

In industry the potential hazards may arise from (i) combustible fluids that may get trapped in insulation materials surrounding heated pipes, and (ii) fires that may result from the exothermic decomposition or oxidation of materials in a processing plant when they come into contact with a hot component. Both types of problems are being investigated from experimental and theoretical points of view.

SELECTED PUBLICATIONS

J.F. Griffiths and C. Mohamed, Experimental and numerical studies of oxidation chemistry and spontaneous ignition phenomena, p545 - 660, Chapter 6 in Comprehensive Chemical Kinetics, vol 35, Low-temperature combustion and autoignition, ed. M.J. Pilling, Elsevier, Amsterdam, 1997

J. Brindley, J.F. Griffiths, A.C. McIntosh and J. Zhang, effects of vaporization, diffusion and condensation on the combustion of reactive fluids in hot, porous media, Proc. R. Soc. Lond., A, 456: 997 - 1017 (2000)

R. Fairlie, J.F. Griffiths, K.J. Hughes and H. Pearlman, Cool flames in space: experimental and numerical studies of propane combustion, Proc. Comb. Inst., 30, 1057, 2005

K. J. Hughes, J. F. Griffiths, M. Fairweather and A. S. Tomlin, Evaluation of models for the low temperature combustion of alkanes through interpretation of pressure - temperature ignition diagrams, Physical Chemistry Chemical Physics, 2006, 3197 - 3210