Numerical analysis of filtration pressure drop and inertial collection efficiency for elliptical fibers
ZHU Hui1,2, YANG Hui1, 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 the inertial collection efficiencies of particles by elliptical fibers and filtration pressure drop. The viscous flow fields for single elliptical fiber were determined by solving the Navier-Stokes equation numerically, and the effects of the following parameters, such as orientation angle (θ), cross-section aspect ratio (ε) and packing density (C) on the filtering performance were discussed. The results showed that the filtration pressure drop for elliptical fibers increased with the increasing aspect ratio for large orientation angle but decreased for small orientation angle. With the same cross-section aspect ratio, the filtration pressure drop increased with the increasing orientation angle. The efficiency of elliptical fibers with larger orientation angle and cross-section aspect ratio was higher than that of circular fibers for intermediate and high-inertia particles, whereas for low-inertia particles, the elliptical fibers with small orientation angle showed higher collection efficiency. The quality factor, an indicator of the ratio of the collection efficiency to the pressure drop, was used to evaluate the comprehensive performance of the elliptical fibers. It was found that the elliptical fibers with large aspect ratios (i.e., long and slim elliptical fibers) showed higher the quality factor (i.e., better comprehensive filtration performance) in capturing intermediate and high-inertia particles when the orientation angle was about θ=45°. For low-inertia particles, the elliptical fibers with major axis parallel to the incoming flow might have filtration performance advantages.
朱辉, 杨会, 付海明, 亢燕铭. 椭圆纤维过滤压降与惯性捕集效率数值分析[J]. 中国环境科学, 2019, 39(2): 565-573.
ZHU Hui, YANG Hui, FU Hai-ming, KANG Yan-ming. Numerical analysis of filtration pressure drop and inertial collection efficiency for elliptical fibers. CHINA ENVIRONMENTAL SCIENCECE, 2019, 39(2): 565-573.
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