Dean Langley, Physics
An acoustic levitator is able to levitate small particles, such as pieces of Styrofoam or water, by creating standing sound waves. The levitator produces a sound wave, which is then reflected back on itself by a reflector, creating the standing waves. These standing sound waves can be observed using schlieren optics. An LED point source light is sent through the air between the levitator and the reflector and reflected off a mirror towards a camera. In front of the camera is a small partition; if there is no disturbed air between the levitator and the reflector (no standing sound waves), the camera captures nothing, but if there is disturbed air (standing sound waves), the light is refracted by the disturbed air, misses the partition, and enters the camera, allowing the standing waves to be captured by the camera. In this experiment, the heat produced by the acoustic levitator would interfere with the capture of the standing waves as the heat waves would refract the light by a greater factor than the sound waves did. I had two objectives in this experiment; to reduce the heat in the acoustic levitator system and to observe how particles behaved when levitated by the acoustic levitator and reflected by different shapes of reflectors. I was able to significantly reduce the heat in the system by using Peltier cooling disks, while also being able to observe the behavior of pieces of Styrofoam as they were levitated by the levitator.
Wetzel, Samuel, "Reducing Heat in an Acoustic Levitation System" (2019). Celebrating Scholarship and Creativity Day. 86.