臺灣大學: 機械工程學研究所潘國隆張書凱Zhang, Shu-KaiShu-KaiZhang2013-04-012018-06-282013-04-012018-06-282010http://ntur.lib.ntu.edu.tw//handle/246246/256219本文利用Fluent6.2套裝軟體分別模擬兩種不同形狀鈍體(bluff)的燃燒器，分別為圓盤(disk)鈍體和帽頂(cap)鈍體，並且與實驗做比較。文中藉由固定空氣噴流速度，改變中心燃料噴流的速度，分別探討不同型態的火焰燃燒結構，分別為迴流(recirculated)火焰、中心噴流主導(central-jet dominated)火焰及似噴流(jet-like )火焰，分別觀察冷流場和反應流場迴流區之間的差異，並觀察CH和OH莫耳分率分布的情況，以觀察火焰外形分布。使用帽頂鈍體的目的是希望燃料和空氣能先在帽頂鈍體內部產生部分預混，在到帽頂鈍體外部達到二次混合，使燃料和空氣混合狀態更好，以增進燃燒效能。This study focuses on numerical simulation for bluff body burner with Fluent6.2, We compare numerical results with the experimental ones by disk bluff body and cap bluff body. The annulus air jet velocity is fixed and the central fuel jet velocity is changed, the flame structure is classified into three stable modes: recirculation zone flame, jet-dominated flame and jet-like flame. We compare recirculation zone by cold reacting flow and combusting flow, and observed the CH and OH mole fraction distribution. Followings are the purpose to use cap bluff body: first, we make fuel and air to be premixed in the cap bluff body. Then, recirculation zone let the mixed gas be secondly mixed, as the mixed gas drift out from the cap bluff body. This can make the mixing process better and improve combustion efficiency.2219833 bytesapplication/pdfen-US圓盤鈍體帽頂鈍體迴流區disk bluff bodycap bluff bodyrecirculation zonethesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/256219/1/ntu-99-R97522117-1.pdf