CALCULATION OF HIGH-PRESSURE COUNTERFLOW DIFFUSION FLAMES UP TO 3000 BAR

The combustion of methane, hydrogen and carbon monoxide at atmospheric pressure in one-dimensional diffusion flames was quantitatively descr ibed with computer simulations by Warnatz et al. and others. The prese nt paper extends the one-dimensional flame description from dilute gas regions to pressures of 3000 bar, where particles are mostly in conta ct with each other. A realistic equation of state with repulsion and a ttraction terms is used. Transport phenomena are modelled with a modif ied Enskog equation. A special problem arises from the stiffness of th e systems of differential equations. Integration uses methods develope d by Deuflhard et al. Flames of methane and hydrogen burning in mixtur es with argon or supercritical water with injected oxygen are simulate d and discussed. Profiles of temperature and other functions at high p ressures through the reaction coordinate are shown. The width of the r eaction zone is narrowed to less than 5% if pressure is increased from 1 to 1000 bar. Maximum temperatures of 3500 K are attained with CH4/A r-O2-flames. Maximum name temperatures decrease with pressure above ab out 500 bar. Several concentration profiles including those of H- and O- radicals and H2O2 are presented. Comparison with recently measured high pressure flame temperatures is made.