Carrier-phase DNS of pulverized coal particle ignition and volatile burning in a turbulent mixing layer

Detailed simulations for flamelet modelling of SOx formation from coal

“…First, the recently developed detailed SO x formation mechanism by Gersen et al [28] (including 63 sulfur-containing species) and the reduced mechanism by Cerru et al [29] (including 12 sulfur-containing species) [29] are compared for combustion in a plug flow reactor (PFR). For better comparability to our earlier work the SO x formation mechanisms are embedded in a core C-H-O oxidation mechanism for homogeneous chemistry [9,25]. Following this, our earlier PCC-FPV model [16] is extended to consider SO x formation and results from direct chemistry (DC) integration and FPV tabulation are compared within Euler-Lagrange simulations of PCC in a laminar counterflow burner.…”

“…Knappstein et al [20] studied volatile combustion from single particles in laminar flow and compared reference direct chemistry simulations to a premixed flamelet (FGM) approach. Rieth et al [25] conducted CP-DNS of coal combustion in a reacting shear layer of coal particles entrained in air (upper stream) mixing with hot lean combustion products (lower stream), employing a relatively detailed volatile composition and homogeneous chemistry. Farazi et al [21] studied coal particle stream ignition in laminar flow using a detailed devolatilisation model and varied coal loading, gas temperature and velocity.…”

“…They identified both premixed and non-premixed combustion zones and found that overly rich mixtures -due to high particle equivalence ratios or fast devolatilisation from small particles-promote extinction and that mild turbulence promotes combustion, whereas strong turbulence suppresses it. Rieth et al [25] conducted CP-DNS of coal combustion in a reacting shear layer of coal particles entrained in air (upper stream) mixing with hot lean combustion products (lower stream), employing a relatively detailed volatile composition and homogeneous chemistry. Ignition was found in lean regions around particles entrained into the lower oxidising stream and at late times combustion occurred in the non-premixed mode in a lower flame, whereas partially premixed combustion with significant two-phase heat transfer was observed at the edge of particle-laden upper stream.…”

Towards the Suitability of Information Entropy as an LES Quality Indicator

“…Parallelization is achieved through domain decomposition and MPI. The code has been used in many LES studies Stein et al (2011);Pettit et al (2011); Rieth et al (2017), some of them highly resolved, achieving DNS-resolution away from the burner, and DNS of pulverised coal flame ignition Rieth et al (2018). Turbulent initialization and inlet data are obtained by an efficient implementation Kempf et al ( 2005) of Klein's well-known inflow data generator Klein et al (2003).…”

Drag force for a burning particle

“…Another widely used drag force correlation is put forward by Schiller et al [4]. These drag laws are of great importance for describing the momentum transfer for dilute multiphase flow simulations [5][6][7].…”