人体呼吸健康研究:N95过滤式面罩呼吸器的佩戴性能(英文版)
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02 Chapter 2 Study of the filtration performance of multi-fiber filters

Introduction

Model of multi-fiber filters

Filtration efficiency and its optimization

Conclusion

Fibrous media is the most common method of filtration,which is generally characterized by its pressure drop and filtration efficiency.In this chapter,the CFD technology was applied to simulate the filtration performance of multi-fiber filters.The pressure drop and filtration efficiency with different fiber arrangements,fiber diameters,face velocities and particle sizes were studied.It was found that filtration efficiency changed with the face velocity for different particle sizes.The layered structures with the same fiber diameters and total solid volume fraction (SVF) were compared,indicating that the dense-sparse structure had the highest filtration efficiency for all the simulated particle sizes at the cost of high pressure drop.Then the dense-sparse structure was optimized to achieve a better filtration performance by using less tiny fibers in the front-row and removing some fibers in the back-row.