MFIX-Exa was used to simulate NETL’s 50kW chemical looping reactor (CLR) with the low-resolution particle-in-cell (PIC) model. The PIC model resolves the geometry on a 4mm fluid mesh and each parcel has a statistical weight of 512 (i.e., each parcel represents 512 particles). The flow boundary conditions were gradually increased to their steady-state values over the first second of simulation. Five additional seconds were simulated, reaching a quasi-steady operating condition with respect to the mass distribution. The end of this simulation at t = 6s will be used as the starting point of a high-fidelity discrete element method (DEM) simulation. MFIX-Exa’s pic2dem restarter application will be used to refine the fluid mesh by a factor of 8^3 and convert the parcels to individual 200 micron particles, over five billion in total.

v2: This is the second completed PIC simulation of the CLR (with some probing tests in between), the previous run can be seen here https://edx.netl.doe.gov/dataset/mfix-exa-pic-simulation-of-netl-50kw-clr. Relative to the previous simulation, the primary flow in the air reactor has been decreased to reduce the circulation rate. This change keeps material from plugging up the cyclone so quickly. The second change was the increase the flow rates in L-valve, which was intended the help keep CO2 from leaking into the air reactor. Although the higher L-valve flow rates delayed the CO2 leakage, it was still able to break through the L-valve and reach the air-reactor. Further study into the optimal L-valve setting is ongoing.