Design and prototype manufacturing of propellers used in drones using composite materials

Drones are unmanned aerial vehicles that have been used in many sectors from past to present and are controlled by one person, as well as video recording and taking pictures. While these vehicles were first used in times of war, now they are again outside the military field; It is used in many places where manpower is required such as package service, control and spraying of agricultural areas, irrigation. It can be produced in different sizes, materials and weights depending on the usage areas. Due to the high usage areas of drones, the need for these tools is increasing day by day. Drones tend to evolve constantly, from their propeller to their battery, from their control boards to their motor. As a result of this development, many countries have made and continue to invest more each year for the drone industry. One of the most important investments made is in the propeller section. Propellers are an important part that allows the drone to move through the air. In the early days, as the propellers were worn out during the war, the same propeller was exchanged for a new one regardless of the reason. Afterwards, scientists thought about the subject and made researches to increase the strength of the propeller and provide better maneuverability. After the wooden propellers, metal propellers, plastic propellers and later composite propellers have started to be used. The use of composite propellers is increasing day by day because wooden and metal propellers are heavy and make a lot of noise, and plastic propellers have less strength. Composite propellers are not only durable but also lighter and less noisy during flight. In this thesis, tensile test, bending test, notch impact test and calcination tests were carried out to determine the mechanical properties of the drone propeller, which is made of two bladed carbon fiber reinforced epoxy matrix composite material. Samples in accordance with ASTM standards were taken from the mechanical tests, and their tests were performed. The test results showed that the propeller has high mechanical properties. The mechanical properties of the propeller were determined and modeled using 3D scanners. Finite element analyzes were performed on the modeled propeller with a computer aided program. Analyzes were made for three different cases. These; flow analysis, rotational structural analysis, and standstill analysis. In flow analysis; the characteristic of the propeller at 5000 rpm was checked; buoyancy force, air resistance on the propeller and air flow velocity were analyzed. In the structural analysis in rotation; The effect of the air resistance applied by the propeller at 5000 rpm on the propeller on the propeller was analyzed. In the standstill analysis, the effect on the propeller is analyzed when the engine is running and the propeller does not rotate due to an obstacle, although it applies force to the propeller. As a result of the analysis, it was determined that the amount of deformation was the least at the wing tips and the most at the middle of the propeller. In addition, the most stress occurred at the wing tips and the least stress was seen in the middle of the propeller.