Yasui Kyuichi, Tuziuti Toru, Kozuka Teruyuki, Towata Atsuya, Iida Yasuo
National Institute of Advanced Industrial Science and Technology (AIST), 2266-98 Anagahora, Shimoshidami, Moriyama-ku, Nagoya 463-8560, Japan.
J Chem Phys. 2007 Oct 21;127(15):154502. doi: 10.1063/1.2790420.
Numerical simulations of nonequilibrium chemical reactions in a pulsating air bubble have been performed for various ultrasonic frequencies (20 kHz, 100 kHz, 300 kHz, and 1 MHz) and pressure amplitudes (up to 10 bars). The results of the numerical simulations have indicated that the main oxidant is OH radical inside a nearly vaporous or vaporous bubble which is defined as a bubble with higher molar fraction of water vapor than 0.5 at the end of the bubble collapse. Inside a gaseous bubble which is defined as a bubble with much lower vapor fraction than 0.5, the main oxidant is H2O2 when the bubble temperature at the end of the bubble collapse is in the range of 4000-6500 K and O atom when it is above 6500 K. From the interior of a gaseous bubble, an appreciable amount of OH radical also dissolves into the liquid. When the bubble temperature at the end of the bubble collapse is higher than 7000 K, oxidants are strongly consumed inside a bubble by oxidizing nitrogen and the main chemical products inside a bubble are HNO2, NO, and HNO3.
针对各种超声频率（20千赫、100千赫、300千赫和1兆赫）以及压力幅值（高达10巴），对脉动气泡内的非平衡化学反应进行了数值模拟。数值模拟结果表明，在接近气态或气态的气泡内部，主要氧化剂是OH自由基，这里将接近气态或气态的气泡定义为在气泡坍缩末期水蒸气摩尔分数高于0.5的气泡。在气态分数远低于0.5的气态气泡内部，当气泡坍缩末期的气泡温度在4000 - 6500 K范围内时，主要氧化剂是H₂O₂；当温度高于6500 K时，主要氧化剂是O原子。从气态气泡内部，相当数量的OH自由基也会溶解到液体中。当气泡坍缩末期的气泡温度高于7000 K时，气泡内部的氧化剂会通过氧化氮气而被大量消耗，气泡内部的主要化学产物是HNO₂、NO和HNO₃。
Zotero 插件