本文以實驗方法與數值模擬探討氫氣、甲烷在多孔性介質燃燒爐中的燃燒現象。實驗依多孔性陶瓷介質排列方式及間隙的有無分為四種爐體，以LabView程式配合資料擷取卡控制各氣體流量、量測火焰溫度、速度與污染物的排放量，而數值模擬則利用熱流計算軟體STAR-CD以二維圓柱座標建構多孔性陶瓷介質燃燒爐，另外加入額外的副程式，以離散座標法來求解輻射熱傳方程式。 文中探討甲烷、氫氣及空氣混合氫在多孔性介質爐中之燃燒現象。討論爐體結構、當量比、流速、氫氣莫爾分率的改變對火焰造成的影響，並探討一氧化碳及氮氧化物對以上各參數之影響；在數值模擬方面以爐體B為爐體模型，進一步探討熱傳導係數、對流熱傳係數、光學厚度、散射比等的改變對燃燒現象之影響。 爐體以三明治結構表現的效能最好，可燃範圍相當寬廣，貧油極限可至當量比0.3以下；間隙的存在會改變火焰穩定的狀態，對爐體D而言，同一火焰速度可存在兩不同的穩定位置；添加氫氣對火焰溫度無明顯變化，但可增加火焰速度，約為自由火焰的6至9倍；對流熱傳係數及氫氣莫爾分率增加會使火焰位置往上游移動；光學厚度增加及散射比接近0.35時，氣體溫度曲線會下降。 The lean combustion of hydrogen/methane mixtures within a highly porous medium has been investigated by experiment and numerical simulation. According to the ceramics arrangement and the gap, four burner structures are built. we use the LabView program to measure the flow rates, flame temperature, the NOx/CO emission. for the numerical simulation. we use STAR-CD to build a model and to compute the solution. results show that for burners without a gap, the flame tends to stabilize at the upstream half. for the burners with a gap, the flame can stabilized in either the upstream half ot the downstreams one. Using small-pore ceramics blocks at the inlet and exit can cut radiative heat loss and lower the lean limit. Addition of hydrogen in the fuel doesn't change the flame temperature greatly. the flame speed, however, increases with the hydrogen fraction in the fuel.
