[peincce2023]

At present, a slit flow is used to test the ability of calculating compressible flow of standard BGKLBM. We know that the standard LBM equation is used to calculate weak compressible flow. Then, I set up a slit of 10 micron *500 micron and simulated it with a lattice of 20*1000. The medium is air, the upper and lower walls are partially rebound, and the inlet is given 1.5 times atmosphere. When the outlet is given to 1 atmospheric pressure, the compressibility effect is very obvious. However, there is a big difference between the results of my LBM and those of Fluent, but the maximum velocity value does not reach the limit of 0.3Ma. When the pressure difference is reduced, the gap between LBM and Fluent is decreasing, so I want to know whether it is because the pressure ratio is too large. Beyond the computing power of standard LBM, or for some other reason, thank you very much! The velocity cloud image of the LBM is shown in the figure below.