Flow simulations on modified aero-propellers

In this project, steady airflow is simulated around a propeller using the CFD software Fluent from ANSYS Student. The propellers for the simulations were a model propeller and a modified propeller with sawtooth serrations at its trailing edge. The fluid domain was built around the propeller and meshed with different settings while maintaining the number of cells in the mesh did not exceed the given limit from ANSYS Student. Flow simulations were then run on Fluent for different flow velocities using a medium mesh, a fine mesh, and a medium mesh with body and face element sizing, for both original model propeller and modified propeller. The results such as the thrust and power coefficients, velocity and pressure distribution, and acoustic power level were compared between the propellers and the meshes. Different meshes gave similar results for the thrust coefficient, power coefficient, velocity distribution of the airflow and pressure distribution on both model and modified propellers. The coefficients of thrust and power of the model propeller, calculated from the results of the flow simulations, were respectively around 0.04 and 0.02 lower than experimental results using the same type of propeller for a range of flow velocities, while modified propeller has thrust and power coefficients reduced by about 18% and 12 % respectively when working at low velocities. On the other hand, the reduction in acoustic power level could not be estimated surely as different mesh showed different degree of noise reduction.Bachelor of Engineering (Aerospace Engineering