Simulation of dust deposition process in ceramic filter under different filtration modes by a novel CFD-based method

Abstract

In this study, the dust deposition process in the ceramic filter of the updraft, tangential, and downdraft flow filtration mode was modeled by a novel CFD-based method, in which a unique mesh grid zone referred to as “dust cake zone” was created to simulate the actual dust cake layer, and grid cells located in the same line were linked together by a fast neighborhood search algorithm to model the actual dust cake growth path. Next, a simulation of the updraft flow filtration (UFF) mode was first carried on and compared to the related experiment in detail to determine the optimal simulation setting. Then, the simulations of the tangential flow filtration (TFF) and downdraft flow filtration (DFF) mode were performed based on the verified CFD settings of the UFF mode, which was able to reduce the pressure drop relative error to less than 6%. Furthermore, the simulation results of these three kinds of filtration modes were carefully analyzed and compared. It was found that the dust cake distribution varied dramatically among different filtration modes, which was due to different patterns of the vortex-flow forming near the candle surface. Some less-particle-deposition-zones can be found on the ceramic candles’ lower portion, middle-lower portion and upper portion in the UFF, TFF and DFF mode, respectively. Moreover, the TFF mode had the lowest pressure drop growth rate, while the most uniform dust cake layer was formed in the DFF mode.