Hallez L, Touyeras F, Hihn J Y, Klima J
Laboratoire de Chimie des Matériaux et Interfaces Université de Franche-Comté, 25030 Besançon Cedex, France.
Ultrason Sonochem. 2007 Sep;14(6):739-49. doi: 10.1016/j.ultsonch.2006.12.012. Epub 2007 Jan 23.
In order to undertake irradiation of polymer blocks or films by ultrasound, this paper deals with the measurements of ultrasonic power and its distribution within the cell by several methods. The electric power measured at the transducer input is compared to the ultrasonic power input to the cell evaluated by calorimetry and radiation force measurement for different generator settings. Results obtained in the specific case of new transducer types (composites and focused composites i.e., HIFU: high intensity focused ultrasound) provide an opportunity to conduct a discussion about measurement methods. It has thus been confirmed that these measurement techniques can be applied to HIFU transducers. For all cases, results underlined the fact that measurement of radiation pressure for power evaluation is more adapted to low powers (<15 W) and that measurement by calorimetry is a valid technique for global energy measurements. Composites and monocomponent transducers were compared and it appears that the presence of an adaptation glass plate reduces the efficiency of the monocomponent transducers. The distribution of ultrasonic intensity is qualitatively depicted by sono-chemiluminescence of luminol. Finally, the quantity of energy absorbed by samples placed in the sound field is determined and the temperature distribution monitored as a function of wall distance. This energetic balance allows us to understand the global behaviour of all experimental set-ups made up of a generator-transducer-liquid and sample.
为了对聚合物块或薄膜进行超声辐照，本文采用多种方法对超声功率及其在池中分布进行了测量。将换能器输入端测得的电功率与通过量热法和辐射力测量法评估的、针对不同发生器设置的池中超声输入功率进行比较。在新型换能器类型（复合材料和聚焦复合材料，即高强度聚焦超声HIFU）的特定情况下获得的结果，为讨论测量方法提供了契机。由此证实这些测量技术可应用于HIFU换能器。对于所有情况，结果都突出了这样一个事实：用于功率评估的辐射压力测量更适用于低功率（<15W），量热法测量是进行整体能量测量的有效技术。对复合材料和单组分换能器进行了比较，结果显示适配玻璃板的存在会降低单组分换能器的效率。通过鲁米诺的声致化学发光定性描绘了超声强度分布。最后，确定了置于声场中的样品吸收的能量，并监测了温度分布随壁距离的变化。这种能量平衡使我们能够了解由发生器 - 换能器 - 液体和样品组成的所有实验装置的整体行为。
