地球正面臨著空氣汙染以及石油耗竭等危機，世界各地環保意識抬頭，因此環保並且可再生的替代能源將會是世界發展的一大重點，其中生質柴油便是替代汽油的一種生質燃料，能夠使排放廢氣減少，並解具有可被生物分解的特性。傳統製程上，是將油類與醇類再加上催化劑混和，並利用機械攪拌加快轉脂化反應，但後來發現將超音波代替機械式攪拌不只能夠提高產率，也能增加反應速率，其原理為將強度夠強的超音波導入液體中能夠產生空蝕汽泡，而空蝕汽泡崩裂後會使油與醇類產生巨大的接觸面積因而加速化學反應。本研究利用有限元素分析模型結合基因演算法去設計流室式聲化學反應器，並與其它文獻所使用的其它形式之聲化學反應器作產率上的比較。

The world is facing air pollution and petroleum depletion, and environmental awareness has risen around the world, therefore environmentally friendly and renewable alternative energy will be a major issue of the entire world in the years to come. Biodiesel is a promising biofuels which is considered as an alternative to petroleum, it is biodegradable and can reduce the exhaust. In general, we use mechanical stir to accelerate the reaction of transesterification, but the later research has shown that if we apply ultrasound during transesterification instead, not only can it increase the yield dramatically but also accelerate the whole reaction. The reason is due to micro-turbulence generated by the collapse of cavitation bubbles generates enormous interfacial area which results in acceleration of the reaction. In this study, we combine the finite element analysis model with genetic algorithm to design ultrasonic flow cell to compare the performance with different forms of ultrasonic reactors from other research’s results.

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