서강대학교

목차

1 Introduction 1
1.1 Bubble generation in the medical and energy industries 1
1.1.1 Acoustic droplet vaporization 2
1.1.2 Optical droplet vaporization 5
1.1.3 Hydrogen bubble generation 7
1.2 Objective of the thesis 9
2 Part 1: Acoustic droplet vaporization 11
2.1 Materials and method 11
2.1.1 Fabrication of PC droplets 11
2.1.2 Fabrication of NPC droplets 12
2.1.3 Experimental setup 12
2.1.4 Transducer calibration 15
2.1.5 Analysis of images 15
2.2 Results and discussion 18
2.2.1 ADV threshold of PC droplets 18
2.2.2 Growth and detachment on PC droplets 21
2.2.3 Effect of phase change 23
2.2.4 Effect of acoustic pressure amplitude 29
2.2.5 Effect of droplet size 32
2.2.6 Regime map for the dynamic motion of PC droplets on a wall 34
3 Part 2: Optical droplet vaporization 37
3.1 Experiment 37
3.1.1 Fabrication of micro droplets 37
3.1.2 Gold nanoparticles coating on glasses 38
3.1.3 Experimental setup 40
3.2 Numerical modeling 42
3.2.1 Theoretical model for bubble nucleation 42
3.2.2 One-dimensional numerical model for bubble growth 43
3.3 Results and discussion 45
3.3.1 Effect of droplet size 45
3.3.2 Effect of ambient temperature 51
3.3.3 Effect of the number of gold nanoparticles 54
4 Part 3: Hydrogen bubble generation 57
4.1 Materials and method 57
4.1.1 Materials 57
4.1.2 Experimental setup 58
4.2 Results and discussion 61
4.2.1 Overpotential for hydrogen bubble generation 61
4.2.2 Hydrogen bubble production 63
4.2.3 Hydrogen bubble production with ultrasound 66
4.2.4 Effect of ultrasonic on/off time 71
4.2.5 Optimization for hydrogen bubble production with ultrasound 74
5 Conclusion 76
References 79