Investigation of swirl flow in a cylindrical shaped ‘pulverized coal distributor’ using CFD simulation

The uneven distribution of pulverized coal particles at the inlet to the gasifier affects the performance of entrained-bed gasifier. Pulverized coal distributor is developed which distributes the pulverized coal evenly among its’ outlets into subsequent burners of the gasifier for gasification purpose. A three dimensional turbulent gas solid two phase flow model for the pulverized coal distributor is developed in the present study. In this multiphase CFD simulation, the rope like structure formed by the pulverized coal in the pneumatic conveying line which creates non uniformity is taken into consideration. To provide uniform distribution of pulverized coal, jet gas (N2) is introduced into the cylinder which provides swirl motion to the pulverized coal. Variations in the angle of swirl of the jet gas with its’ different positions is analyzed and its impact on the coal distribution at the three outlets of the coal distributor is determined through CFD simulation. The Eurler-Lagrangian approach is used to simulate the dilute phase particle motion. Time averaged conservation equations for mass and momentum and K-Epsilon turbulence model is employed to simulate the carried fluid phase in the distributor.