Image Credits and References:
Video and measurements of single-bubble sonoluminescence (SBSL)
“Single-Bubble Sonoluminescence; HOW TO,” by Reinhard Geisler explains the setup details http://www.macgeisler.de/nld/sbsl-howto.html
The task is to design, build and test two sonoluminescence chambers and demonstrate a glowing bubble in each containing different liquids and gasses. The project is a “Star in a Jar.” Of the two chambers to be tested, one is made from a spherical flask and the other is a cylinder. Each chamber will contain pure deionized, degassed water. In some experiments, the degassed water will be infused with various noble gasses that include Xenon and Neon. The chambers will be driven by piezoelectric transducers (PZT) at supersonic frequencies to match the resonant condition of the chamber’s shape. A match between the acoustic resonance of the chamber and the electrical resonance of the transducers will be monitored using a microphone and an oscilloscope. Electrical resonance occurs when the signals for current and voltage are in phase. Acoustic resonance for the chambers will be calculated and monitored with a microphone to verify when the peak amplitude is achieved. A laser, fast detector and optical scattering system will be used to monitor the collapse of the bubble into a small dot of light, like a distant star.
Level of Difficulty: Low
nonlinear cavitation, ionization, Felipe Gaitan, spectrometer, photomultiplier tube, photodiode, Gustav Mie Scattering (Lorenz–Mie–Debye solution), vacuum degassing, root-mean-square value (rms), piezoelectric
Sonoluminescence: Sound into Light, by Sean McCluney, Thesis, Bachelor of Science in Physics, University of Santa Cruz, June 5, 2010
Electrical Engineer (3) – The Electrical Engineers on the project are responsible for the PZT drive system and the fast electronic amplifiers needed to detect scattered laser light. In the drive system, electrical resonance is achieved by an inductor equipped with a cylindrical ferrite slug that can be adjusted to change the inductance value.
Mechanical Engineer (3) – The Mechanical Engineers on the project are responsible for the two acoustic chamber and the design and construction of a water degassing system that removes dissolved air from distilled water and replaces it with a noble gas. Additionally, the Mechanical Engineers take care to mount the acoustic chambers is a way that does not waste the acoustic power by unwanted fixture vibrations.
Physicist (2) – Physicists on the project are responsible for the two optical systems that detect bubble collapse and allow visitor observation of the stable SBSL through a homemade telescope. Mie scattering requires an optical collector for the scattered light to be focused on a fast photodiode. The scattered laser light will have a predetermined scattering angle for spheres larger that the laser wavelength, as shown in the figure on the right. http://www.philiplaven.com/mieplot.htm. The Physicists will construct a telescope to image the small bubble onto a video camera where the magnified image can be seen by everybody on a large monitor.
Mie scattering polar plot for 0.65 µm red light striking a water droplet of r = 10 µm
Designer (2) – The Designers on the project are responsible for an assembly that supports the equipment for transportation and display. Additionally, the Designers work closely with the Mechanical Engineers to build the water degassing system and develop a method to transport the specially prepared water to demonstrations.
Journalist (1) – The Journalist documents the project’s progress on the website, communicates with the local media, and is responsible for a final report to the principal sponsors and Power Mountain Engineering. The Journalist also works closely with the Multimedia Artist to provide video and graphic art displays for demonstrations that explain the project to the public. The whole project is your project.
Multimedia Artist (1) – The Artist also documents the project’s progress on the website and works with the Journalist to maintain the project’s presence on social media. Additionally, the Artist designs and organizes all public relations events to assure spectator safety and to enhance the community’s awareness of science and technology. The whole project is your project.
Business Manager (1) – The Business Manager is responsible for reporting the project’s progress against a predetermined schedule, determines critical path items to completion, and tracks project spending to assure that costs remain within a fixed budget. The Manager works with all team members to identify problems early and resolve them quickly. The whole project is your project.