非預混之平面噴流火焰在受自激振盪橫向控制時，以實驗方法研究火焰行為與溫度結構。平面噴流是藉由一特別設計的射流振盪器，在噴流出口形成橫向振盪。利用瞬時與長時間曝光攝影技術觀察噴流火焰的行為，火焰之溫度與燃燒生成物的分佈，則分別使用R型熱電偶及燃燒火焰氣體分析儀量測。橫向振盪平面燃燒噴流在出口處形成辮子狀的藍色火焰，而無振盪平面燃燒噴流的出口處則形成層流形式的藍色火焰。橫向振盪平面噴流火焰的三種特徵火焰模態分別為:接觸火焰、過渡火焰及跳離火焰。無振盪平面噴流火焰的三種特徵火焰模態則分別為:動量不足火焰、過渡火焰及動量支配火焰。在高雷諾數時，橫向振盪平面噴流火焰的反應支配區域比無振盪平面噴流火焰短且寬。此外，橫向振盪平面噴流火焰呈現較大的二氧化碳及較小的未燃燒碳氫化合物，也呈現部份預混火焰的特性。無振盪平面燃燒噴流火焰則呈現擴散火焰的特性。概括來說，因為射流振盪器的橫向噴流振盪形成渦漩結構，並且渦漩結構破碎造成高紊流擾動，使得噴流橫向擴散與混合增強，橫向振盪平面噴流火焰比無振盪平面噴流火焰具有較佳的燃燒性能。針對平面噴流的長寬比及同向空氣噴流對平面燃燒噴流的效應，對於火焰行為及溫度結構的影響，亦被研究與探討。

The flame behavior and thermal structure of combusting non-premixed plane jets with and without self-excited transverse oscillations were investigated experimentally. The transversely-oscillating plane jet was generated by a specially designed fluidic oscillator. The flame behavior was studied using the instantaneous- and long-exposure photography techniques. Temperature and combustion-product concentration distributions were measured using a fine-wire type-R thermocouple and a gas analyzer, respectively. The results showed that the combusting transversely-oscillating plane jets had distributed blue flames with plaited-like edges, while the corresponding combusting non-excited plane jet had laminar blue-edged flames in the near field. The transversely-oscillating plane jet flames were categorized into three characteristic flame modes: attached flame, transitional flame, and lifted flame. The non-excited plane jet flames showed three flame modes, viz; momentum-deficit flame, transitional flame, and momentum-dominated flame. At high Reynolds number (Rej > 1204), the transversely-oscillating jet flames were significantly shorter and wider with shorter reaction-dominated zones than those of the non-oscillating plane jet flames. In addition, the transversely-oscillating combusting jets presented larger carbon dioxide and smaller unburned hydrocarbon concentrations, as well as portrayed characteristics of partially premixed flames. The non-oscillating combusting jets presented characteristics of diffusion flames. Generally, the transversely-oscillating jet flame had combustion performance characteristics that were superior to its non-oscillating plane jet flame counterpart. The improved combustion performance of the transversely-oscillating jet was due to the enhanced entrainment, mixing, and lateral spreading of the jet flow, which were induced by the vortical flow structure generated by lateral periodic jet oscillations, as well as the high turbulence created by the breakup of the vortices. The effects of co-flowing air streams and aspect ratios on the flame behavior and thermal structure of gaseous fuel jets issued from rectangular nozzles were additionally investigated and discussed.

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