CFD simulation and analysis for the air flow in the primary air chamber of a supper-critical circulating fluidized bed

In this paper, CFD simulations based on FLUENT were performed for the air flow through the primary air chamber and air-distributor system in a super-critical pressure circulating fluidised bed. To reduce CFD simulation time, a simplified porous media model is used to simulate the pressure drop across the air distributor plate based user-defined function (UDF) in FLUENT. Simulations results for the air flow through the air chamber with three different air inlet supply system, i.e., air inlet form bottom, side and real side of chamber, are given and compared. Key parameters including pressure-drop, velocity and turbulent intensity distribution and profiles in the chamber are given and compared. The optimum air supply system design for primary air chamber is given according to the simulation and analysis results. CFD simulation can be used to optimize the design and scale up for the air supply system in a supercritical pressure circulating fluidized bed.