Numerical analysis of pressure drop and inertial collection efficiency of a single fiber
ZHU Hui1,2, FU Hai-ming1, KANG Yan-ming1
1. School of Environmental Science and Engineering, Donghua University, Shanghai 201620, China;
2. School of Energy and Building Environment, Guilin University of Aerospace Technology, Guilin 541004, China
A numerical scheme was developed for calculating single fiber drag force and inertial capture efficiencies of particles, and the viscous flow fields inside a model filter composed by staggered fiber arrays were determined by solving the Navier-Stokes equation numerically. The drag force of single fiber was then calculated for various values of packing density (C) and Reynolds number, and compared with the theoretical predictions by Happel and Kuwabara models, respectively. The results showed that Happel model agreed reasonably well with present numerical calculations when C < 0.045, giving a better prediction than that by Kuwabara model, while Kuwabara model was more reliable for C > 0.08.The single fiber collection efficiency due to inertial impaction was also obtained from the rigorous numerical simulations of trajectories of particles based on the viscous flow field solved by numerical simulations, and the effects of filtration velocity, particle density and packing density were discussed. The results showed that there was a critical particle diameter for inertial collection, below which particles failed to be captured by fibers. Based on the simulation results, a new correlation equation for predicting the single fiber drag force was presented, and a new correlation for single fiber efficiency due to inertial impaction was derived as a function of Stokes number (St) and C for St ≤10 and 0.01≤ C ≤0.1.
朱辉, 付海明, 亢燕铭. 单纤维过滤阻力与惯性捕集效率数值分析[J]. 中国环境科学, 2017, 37(4): 1298-1306.
ZHU Hui, FU Hai-ming, KANG Yan-ming. Numerical analysis of pressure drop and inertial collection efficiency of a single fiber. CHINA ENVIRONMENTAL SCIENCECE, 2017, 37(4): 1298-1306.
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