靜電集塵器(Electrostatic precipitator, ESP)為一種高效能的空氣清淨裝置，可以有效去除空氣中較大的懸浮微粒(Particulate matter, PM)。但因微粒充電機制的關係，使直徑介於0.1 μm到1 μm之間的微粒較不容易被收集，而將微粒合併在一起，提升微粒遷移率，是改善靜電集塵器對次微米微粒收集不易的方法之一。本研究在微粒充電區前加裝8種不同配置的紊流合併區流道作為紊流合併器(Agglomerator)，並使用微粒影像測速儀(Particle image velocimetry, PIV)技術探討紊流合併器內部的流場特性，比較其在不同配置下的合併效率，以及加裝合併器後對次微米微粒的收集效率。本論文中分別探討肋條截面形狀、狹縫以及與壁面的夾角對合併效能之影響。從流場可視化的實驗結果顯示，Z字形截面的肋條能夠產生比四邊形截面的肋條更強且更大範圍的紊流動能(Turbulent kinetic energy, TKE)，且在肋條中間開一道狹縫有助於提升肋條後方的紊流動能，而傾斜於壁面135°的肋條則會降低流道內的紊流動能。粒徑量測的結果顯示，紊流合併器能夠確實將次微米微粒合併成較大的微粒，其合併效率與產生的紊流動能有關，且可以有效提升靜電集塵器對次微米微粒的收集效率，但因合併的強度不高，所以合併後的微粒在碰撞到收集板後，有可能破碎回細小的微粒。

Electrostatic precipitator (ESP) is a high efficiency particle removal technique that can efficiently remove larger Particulate matter (PM). However, due to the limitation of the charging mechanism, the collection efficiency for PM between 0.1-1 μm is lower. One of the methods to solve this problem is to use agglomerator to coagulate the particles together into a larger particle for charging effect. In this study, the flow characteristics inside eight different designs of turbulence agglomerator which was installed before charging section of the ESP were observed by Particle image velocimetry (PIV). By using particle counter, the agglomeration and collection efficiency between different turbulators configuration were also compared. The effects of the ribs profile, slit and inclined angles were investigated. The flow visualization results show that Z-type turbulators create stronger and larger area of turbulent kinetic energy (TKE) than the quadrilateral-type turbulators. The slit in the middle of the ribs can increase the turbulent kinetic energy behind the ribs, while the 135° inclined angle reduces the turbulent kinetic energy. The particle sizer measurement results suggest that turbulence agglomerator successfully coagulated the sub-micro particles into larger particles, and the efficiency is related to the turbulent kinetic energy (TKE). The agglomeration of particles improves collection efficiency of the ESP for sub-micro particles, but coagulated particles may break into sub-micro particles again while colliding on the collection plate due to low cohesion force.

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