Explore methods to reduce noise for propeller drones

This report’s objective is to explore methods to reduce noise for propeller drones. Noise is one of the major factors that limits the range of drone application in daily life. Long time exposure to noise will cause damage to human hearing and psychological health according to study performed [1] There are two parts for this report. First part of this report is to focus on the literature review. Properties of sound will be studied in this part. What is sound, how does sound propagate and diffraction, reflection properties of sound wave. The second part of this report focus on analyzing noise source from drone and methods to reduce the noise. The major noise generated by small type of drones can be categorized into structure noise and acoustic noise. Noise caused by aerodynamic plays an important part in drone noise generation. Improved design on propeller tips and trailing edge can help reduced the noise. For propeller tips, change the flat tips to proplet top design by 45 degrees which will have better noise reduction performance. As for trailing edge of propeller, a serrated shape of edge is effective for aerodynamic noise reduction. In order to further reduce the noise level, there are two concept designs mentioned in the last part of this report. They are using corona wind principle and Dyson bladeless fan principle to generate lift force for drones to fly.Bachelor of Engineering (Mechanical Engineering