Abstract:This paper established the flat 3-D mimic structure that was based on the random multi-fiber filter media algorithm. The computational fluid dynamics-population balance model (CFD-PBM) was used to simulate the turbulent aggregation of fine particles during the multi-fiber capture. The partition method was used to solve the population balance equation (PBE). The analysis by the controlled variable method shows that there was apparent particle aggregation behavior in the multi-fiber capturing process. The particle aggregation degree increased with the increasing residence time and gradually stabilizes while t ≥ l/v (dimensional length along with the flow field direction/inlet velocity). When vmax·t ≤ l, the larger the velocity inlet, the larger the particle aggregation degree and the aggregation rate, but the final aggregation degree depends on the velocity inlet and residence time; the larger the particle diameter, the smaller the particle aggregation degree and the aggregation rate. Also, the smaller the ratio of the average particle diameter of the outlet compared with the initial particle diameter. The larger the volume fraction of dust particles, the larger the particle aggregation degree and the aggregation rate. When v=0.1m/s, dp=1.0μm, VF >0.003636, the number concentration logarithmic distribution between Bin-7~Bin-0 shows a linear proportional relationship.
张俪安, 刁永发, 楚明浩, 贾中坚, 沈恒根, 孙静. 多纤维捕集过程中细颗粒湍流团聚模拟研究[J]. 中国环境科学, 2021, 41(10): 4572-4578.
ZHANG Li-An, DIAO Yong-fa, CHU Ming-Hao, JIA Zhong-Jian, SHEN Heng-Gen, SUN Jing. Study on turbulent aggregation characteristics in the process of fine-particle captured by multi-fiber. CHINA ENVIRONMENTAL SCIENCECE, 2021, 41(10): 4572-4578.
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