NUMERICAL METHODS IN PROCESSES OF DESIGN AND OPERATION IN PNEUMATIC CONVEYING SYSTEMS

During design and operation of large dust boilers systems one of the main problems is to provide the required distribution of the air-dust mixture to individual burners. Further, the higher concentration of particles in certain areas of the flow can cause uncontrolled erosion wear of these fragments. For boilers with burners in the corners, just behind the outlet of the mill four-path separator is built-in, whose task is even distribution of air-dust mixture. For numerical analysis Psi-CELL method was used to determine velocity distributions and for calculating particle trajectories Lagrangian method. Numerical calculations of the air-pulverized coal mixture flow through a pipeline with built-in elbow and a four-path separator were prepared. The result of the study showed when a small modification of the test system-by installing the threshold scattering-can reduce dust segregation intensity in the section downstream the elbow. It is also shown that the method adopted to calculate the system allows optimization of the flow for other very complex geometries.