The 20-kHz probe-type sonicator systems were investigated for the enhancement of the cavitational oxidation activity under various geometric conditions including vertical and horizontal probe positions and vessel sizes/volumes as a following study to our previous study. The sonochemical oxidation activity (mass-based I ion generation rate) increased significantly for all vessel size conditions as the probe was placed close to the vessel bottom, owing to the expansion of the sonochemical active zone induced by the reflections of ultrasound at the bottom and the reactor wall. A concentric circular active zone is observed at positions close to the bottom. The highest sonochemical activity was obtained at 1 cm (vertical position) in the 20 cm vessels (input power: 50 %). At the vertical positions of 11 cm to 7 cm, no significant difference in the sonochemical activity was observed for all input power conditions (25, 50, and 75 %) because no meaningful reflections occurred. Higher sonochemical activities were obtained at an input power of 75 % owing to the increased power and strong reflection. The highest cavitational yield considering the energy efficiency was obtained at 6 cm (vertical position) for 75 % of all power and geometric conditions. Horizontal probe position tests showed that the asymmetric formation of the sonochemical active zone could significantly enhance the sonochemical activity. The highest activity was obtained at 1 cm (vertical position) and 2.5 cm (horizontal position) in the 20 cm vessel.

中文翻译：

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20-kHz 探头型超声仪系统中的声化学氧化活性：探头位置和容器尺寸的影响


作为我们之前研究的后续研究，研究了 20 kHz 探头型超声仪系统在各种几何条件下增强空化氧化活性，包括垂直和水平探头位置以及容器尺寸/体积。当探头放置在靠近容器底部时，由于底部超声反射引起的声化学活性区的扩大，在所有容器尺寸条件下，声化学氧化活性（基于质量的 I 离子生成率）显着增加。反应堆壁。在靠近底部的位置观察到同心圆形活动区。 20 cm 容器中 1 cm（垂直位置）处获得最高声化学活性（输入功率：50%）。在 11 cm 至 7 cm 的垂直位置，在所有输入功率条件（25%、50% 和 75%）下，未观察到声化学活性的显着差异，因为没有发生有意义的反射。由于功率增加和反射强，在输入功率为 75% 时获得了更高的声化学活性。考虑到能量效率，在 75% 的所有功率和几何条件下，在 6 厘米（垂直位置）处获得最高空化产率。水平探头位置测试表明，声化学活性区的不对称形成可以显着增强声化学活性。在 20 cm 容器中 1 cm（垂直位置）和 2.5 cm（水平位置）处获得最高活性。