Mechanical Oscillator
A Dremel tool is used to create vibration. The blade of the Dremel moves through angle of 1.5 degrees in each direction with a frequency range of 160Hz to 350Hz. The push-rod connects the Dremel blade to the sample holder allowing the Dremel to operate outside of the icing wind tunnel.
Sample Holder
The sample holder is designed to hold two samples side by side so that a control material can be tested against a super-hydrophobic surface. The angle of attack can be changed by loosening the wing nut, pivoting the sample holder and then re-tightening the wing nut.
Since the sample holder is designed to hold a SHP sample and a control sample it was important to the design that both samples were subjected to the same flow conditions in the icing wind tunnel. The design was verified using SolidWorks FlowWorks to simulate the conditions in the icing wind tunnel.
Photo Interrupter and Data Acquisition System
NI USB-6008 DAQ
A photo interrupter is used to measure the frequency of the Dremel. The blade of the Dremel breaks the beam of the photo interupter sensor during oscillation. The USB-6008 DAQ is connected to the photo interrupter sensor. The DAQ is configured to count when the Dremel blade breaks the beam of the sensor on the down stroke. This count is then transmitted to LabVIEW and used to calculate the operation frequency.