Notes

Slide Show

Outline

1	The ABS Acoustic Bubble SpectrometerÒ
2	Background Bubbles in a liquid are very sensitive to acoustic waves Bubble acoustic cross section >10 times solid particle of the same size Bubbles much more compressible than liquid Bubbles act like a spring-mass oscillating system Mass from liquid inertia Spring constant from permanent gas, …etc Possibility for strong resonance Þ acoustic energy absorption, re-radiation
3	Spherical Bubble Dynamic Equation Spherical Symmetry + Conservation of Mass: Conservation of Momentum Rayleigh Plesset Equation (when linear relationship stress-strain)
4	Small scale oscillations Driving Pressure Bubble Radius RP Equation degenerates to: Þ
5	Resonance
6	Influence of Bubble Distribution on Sound Propagation
7	Dispersion Relations
8	The ABS The ABS Acoustic Bubble Spectrometer^Ò is an acoustics based device that measures bubble size distributions in liquids. Very sensitive to bubbles No need for transparent liquid or “container” Easy to Use Packaged User-Friendly System Near Real-Time measurement Could be part of: an on-line system a distributive placement for large scale applications a long-term continuous monitoring application an off-line post-measurement analysis
9	POTENTIAL APPLICATIONS
10	PC-BASED ABSÒ SETUP
11	User Input - I
12	User Input - II
13	User Input - III
14	User Input - IV
15	Output -I
16	Output -II
17	Recent Validation Experiments
18	Bubble Injector
19	Illustration of the degree of variation in the bubble size distribution measurements
20	VALIDATION
21	CONCLUSIONS