Investigation of Metal Powder Injection into a Combustion Chamber by Large Eddy Simulation for Power to X Studies

Abstract

The numerical modeling and simulation of particle dispersion during the filling process of a tubular combustion chamber are presented. By means of multiphase large eddy simulations (LES) the particle distribution inside a circular diffuser-reactor chamber is studied to analyze the two-phase flow dynamics for metal powder combustion in a tubular reactor with flame propagation. Typical particle accumulations are found that form close to the reactor wall and also particles tend to segregate and preferentially concentrate at vortex surfaces in particle bands. Particle segregation and accumulation effects aside vortex structures are analyzed using the LES approach. The causes of particle segregation and inhomogeneities are studied and measures for its reduction by changes in the reactor design are discussed. Alterations of the diffuser geometry are adapted to minimize the central particle jet formation and the particle distribution inhomogeneities during the filling process.