direct numerical simulation; detailed chemistry ; homogeneous ignition ; turbulent hetero-/homogeneous combustion ; flame extinction
Arani Behrooz Ostadmohammadi, Frouzakis Christos Emmanouil, Mantzaras John, Boulouchos Konstantinos (2018), Direct numerical simulations of turbulent catalytic and gas-phase combustion of H 2 /air over Pt at practically-relevant Reynolds numbers, in Proceedings of the Combustion Institute
, in press.
Ostadmohammadi-Arani Behrooz, Frouzakis Christos Emmanouil, Mantzaras John, Boulouchos Konstantinos (2017), Three-dimensional direct numerical simulations of turbulent fuel-lean H2/air hetero-/homogeneous combustion over Pt with detailed chemistry, in Proceedings Combustion Institute
, 36(3), 4355-4363.
Behrooz Ostadmohammadi Arani, Christos Emmanouil Frouzakis, John Mantzaras, Konstantinos Boulouchos, Direct numerical simulations of turbulent catalytic and gas-phase combustion of H2/air over Pt at practically-relevant Reynolds numbers, in Proceedings of the Combustion Institute
Catalytic processes are of prime interest for many industrial applications ranging from large-scale power generation in stationary turbines and portable power generation in microreactors, to fuel processing and exhaust gas treatment. In large-scale power generation, catalytic combustion approaches appear particularly attractive for the latest combustion technologies aiming at mitigation of greenhouse CO2 emissions. Modern catalytic reactors operate at high pressures where the incoming Reynolds numbers based on the individual catalytic channel hydraulic diameter can reach up to 20,000 at full load operation. At such elevated pressures, gas-phase (homogeneous) chemical reactions cannot be neglected ?even at the very high geometrical confinements of typical catalytic reactors. Therefore, there is a need for reliable numerical models capable of describing hetero-/homogeneous combustion in transitional or fully turbulent channel-flows.Direct numerical simulation (DNS) will be used to investigate, for the first time in the literature, coupled heterogeneous and homogeneous reactions. Detailed catalytic (mean-field surface reaction mechanism) and elementary gas-phase chemistry will be employed in the DNS code to study hydrogen catalytic combustion over platinum. Moreover, an elementary gas-phase reaction mechanism will be used (necessary for describing the major and minor species coupling with the catalytic reaction pathway). The goal is to identify the interactions between turbulence, catalytic chemistry and gaseous reactions leading to the onset of homogeneous ignition and to local flame extinction over catalytic surfaces. The proposed DNS investigation will shed light on conditions of local homogeneous ignition and local flame extinction and their relation to the overlying turbulence levels of the flow. Moreover, the DNS results will further aid the development of advanced Reynolds Averaged Navier Stokes (RANS) and Large Eddy Simulation (LES) models.