樹狀流道於氣溶膠過濾系統中的應用及研發

Abstract

在氣溶膠領域中，已知有許多因素會影響靜電濾材之過濾效率，包括氣溶膠的粒徑、濾材和氣溶膠粒子之電荷量，以及過濾流速等。本研究著重於過濾流速及空氣流場對於靜電濾材之濾效的探討。 在許多研究中已經證實隨著過濾速度的衰減，靜電濾材之濾效會有顯著的提升。因此本論文結合了人體物理學的概念，開發了一種類似肺部氣管流體設計之仿生過濾流道—樹狀流道。利用此流道的等阻抗分流的設計，能夠有效的擴展過濾面積，達到減緩流速的作用，並且還能提供一均勻分布的空氣流場，增進濾材之過濾品質，以期能夠最佳化地使用濾材，提升濾材的使用壽命。 在本研究中同時使用了有限元素分析軟體，來模擬樹狀流道內之空氣流場的分布情形，而由模擬的結果也顯示了此流道具有提供均勻流場及降低整體系統之壓損的優點。而本研究最後更將此樹狀流道應用在實際的過濾情形中，利用3D列印技術，製作出一具有樹狀流道系統之個人化可攜式呼吸防護具，並加以驗證其過濾性能，未來更可將此流道系統應用在生活上許多過濾器中。

In the field of aerosol filtration, many factors are known to affect the filtration efficiency of electrostatic filters, including the particle diameter of the aerosol, the charge level of the filter material and aerosol particles, and the face velocity. In this thesis, the contribution of face velocity on the filtration efficiency of electrostatic filters is investigated and applied. It has been confirmed that the filtration efficiency of the electrostatic filter material improves along with a lower face velocity. To apply this effect, a bionic filtration flow channel that mimic trachea and bronchi tree is applied. It is named as tree-shaped flow channel in this thesis. By using this deign of the flow channel, the filtration area can be effectively expanded to reduce the flow rate, and a uniformly distributed air flow field can be provided to improve the filtration quality of the filter material, and optimizing the use of the filter material to extend the lifetime of electrostatic filter material. In this study, the finite element analysis software was used to simulate the distribution of the air flow field in the tree flow channel. Simulation results also show that the flow channel has a uniform flow field and reduces the pressure drop of the overall filtration system. At the end of the study, the tree flow channel was applied to an actual filtration situation, and a personalized portable respiratory protection device with a tree-shaped flow channel system was fabricated by using 3D printing technology, and the filtration performance was verified.