A Coupling Algorithm for Eulerian- Lagrangian Simulation of Dense Gas- Solid Reacting Flows on Unstructured Mesh Jian Cai Assistant Professor University of Wyoming Combustion research at UW New combustion program Mechanical Engineering Department Four junior faculty members Coal utilization Research topics Laser spectroscopy Turbulent combustion experiments and modeling Pulverized and dense coal combustion Radiation modeling and measurements 2 Coal combustion and gasification What is the limiting factor for accuracy? What is the next limiting factor? 3 TurbulenceRadiation MultiphaseChemistry E-L models for multiphase flows Advantages in accounting for changes of Particle size and distribution Heat transfer Heterogeneous reactions History between different particles Composition Temperature Disadvantages Computational cost Unknown surface properties 4 OpenFOAM Lagrangian existing capabilities Pulverized coal combustion Collisional non-reacting particles Eulerian Solving transport equations Needs a new coupling algorithm 5 FVM: unstructured collocated mesh 6 Coupled equations ModelCoupling variables IncompressibleU, p CompressibleU, p, T, Multiphase compressibleU, p, T, , 7 Coupling algorithm 8 Energy, species equations + Equation of state Density update Velocity-pressure coupling Reacting test case 9 Pseudo 2D DPM Char 2.5mm parcels 3s physical time CFB Zhou et al CES MPPIC Sand 213m 0.3Mparcel x 1000p/parcel 10 Particle volume fraction 11 Conclusions Eulerian-Lagrangian coupling algorithm Unstructured collocated mesh Gas-solid dense reacting flows Computational cost is the major limitation MPPIC faster than DPM 12