本研究主要探討具有穿孔之不鏽鋼/白金觸媒微管燃燒器的燃燒性能與優化研究。由於燃燒過程會伴隨著化學反應、熱傳導與質量擴散等不可逆性的過程發生，而這些不可逆性的過程稱之為熵。熵之生成會造成能量損失，然而這些能量損失無法藉由實驗測得求得，因此需要藉著模擬之幫助以探討微反應器內部能量損失之來源。藉著分析熵生成率之後，可以進一步求得微燃燒器的熱力學第二定律效率，以判別燃燒器性能。
繼前人的研究得知，帶有穿孔式的不鏽鋼/白金觸媒微管將有利於火焰穩住於微反應器中，其原因在於孔洞的設計能提供微反應器一個低速帶且有利於內、外兩流道之流體混合。然而，孔洞數量與孔徑大小之研究尚未深入探討，因此本研究提出三種不同之燃燒器設計，依固定白金面積設計出4個與6個孔洞數量，旨在探討白金用量相近的情況下，孔洞數量對於燃燒性能之影響，並以4個孔洞之設計探討孔徑大小，孔徑直徑分別為1公厘和1.5公厘。
然而，本研究提出3種燃燒器的孔洞設計以及針對會影響燃燒效率的四種參數進行探討，其中討論的參數包含甲烷/空氣的流速、氫氣/空氣的流速、甲烷/空氣的當量比，以及氫氣/空氣的當量比。隨著操作區間的搭配，將會有許多參數組合，若要探討所有排列組合條件的性能，勢必會浪費許多時間與金錢。因此本研究利用克里金代理優化模型協助以較少的組數得到然燃燒效率的趨勢，並且能以一定量的實驗組數去建立優化模型。其中，所建立的克里金代理優化模型可以成功預測3種燃燒器的燃燒效率，以及其燃燒模態的區間界定。例如，在六個孔洞設計中，氫氣/空氣速度、甲烷/空氣速度、甲烷/空氣的當量比與氫氣/空氣的當量比的敏感性係數值分別為 -1.7、-0.22、0.4 和 0.15。代表氫氣/空氣的當量比在六個孔洞設計中將影響燃燒效率甚大。

This study discusses the combustion performance and optimization of stainless steel−platinum segmentation micro combustors. The combustion processes accompany irreversibilities such as chemical reaction, heat conduction, and mass diffusion. These irreversibilities are so-called entropy generation. The generation of entropy will cause energy loss. Still, these energy losses cannot be determined throughout conducting experiments. The insight of energy losses in the microreactor needs to be explored with simulation assistance. By analyzing the entropy generation rate, the combustion-based second law efficiency of the stainless steel−platinum segmentation micro combustor can be further obtained to determine the combustion performance of the micro combustor.
From the previous studies, the stainless steel−platinum segmentation micro combustor was well-known that flames could be stabilized in the microreactor. The reason is that the design of the perforated holes can provide a low-velocity zone to facilitate the flow mixing between the inner and outer tubes. However, the research on the pore number and size of the perforated hole array has not been thoroughly explored. Therefore, this study proposed three different combustor designs. The pore numbers of 4 and 6 holes were designed according to the fixed platinum catalyst area. According to the fixed platinum catalyst area, the pore number of the perforated holes is to explore the influences on the combustion performance. Also, the parameter of the pore diameter was chosen as 1 mm and 1.5 mm in diameter to investigate the effect on combustion performance.
Three kinds of microreactor designs and four parameters will affect combustion efficiency. The inlet velocities of the methane−air mixture, the inlet velocity of the hydrogen−air mixture, the equivalence ratio of the methane−air mixture, and the equivalence ratio of the hydrogen−air mixture were discussed in this study. There will be many parameter combinations in the permutation of the operating condition. If all conditions were implemented, it would cost colossal time and expense. Therefore, this research employed the Kriging surrogate optimization model to predict the combustion efficiency tendency with fewer experimental runs. Utilizing the Kriging model can also obtain the sensitivity coefficient of the parameters and demonstrate the most influential parameter on combustion efficiency. For example, the sensitivity coefficients for H2−air velocity, CH4−air velocity, ERH2 and ERCH4 in six percolated holes design are −1.7, −0.22, 0.4, and 0.15, respectively. It represents the ERH2 is dominant in the combustion efficiency of the six percolated holes design.

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