Summary: | 碩士 === 國立成功大學 === 航空太空工程學系碩博士班 === 100 === This thesis presents the design and development of an electromagnetic shock wave generation based on repetitive triggering method of finite amplitude shock pulse in liquids. This device consists of a high-voltage, 2 to 3-µF, 6-kV capacitor which is discharged to a flat coil. An insulated metal disk is placed in close proximity to the coil and is mounted in a water-filled tube. Lorentz force induced by eddy currents in the disk repluses the disk away from the coil. The disk repulsive acceleration produces a pressure shock wave which is focused to the target using acoustic lens. Theoretical analyses of the electrical and control circuits have been developed with details of components and materials. In this study, a high voltage power circuit is developed as shock wave generator for experiment. By increasing the capacitance to lift energy level, a higher focusing pressure can be achieved. A generalized relationship between the acoustic pressure and capacitance voltage also has been evaluated. The modeled shock wave generator can produced 0.06 to 0.104 mJ/mm2 energy which has a potential application for ESWT, e.g. lipotripsy, messaging and other aesthetic application. However, higher intensity can be achieved by adding extra capacitor to the circuit. Finally, the necessary control signals, acoustic field, peak measured acoustic pressure and shock wave intensity have been measured in experiments.
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