CFD Analysis of a Novel Propeller Design Operating at Low Reynolds Number

The aerodynamic performance of a propeller is characterized by the thrust produced, torque and efficiency. In this paper, novel blade shapes are tested using the technique Computational Fluid Dynamics (CFD). The blade shapes are based on a passive slotted design in which slots are present on the suction side i.e. on the upstream front side of the blade. Two slotted design models are tested using the commercial CFD solver ANSYS Fluent. The slotted designs are identical in terms of slot geometry (0.1 mm width, 0.2 mm depth) but differ in the location of slot along chord from leading edge (0.206c and 0.382c). In order to test the modified designs, a validation study of the baseline model of a propeller is conducted. Then slotted designs comprising two models are tested and compared to baseline design. The propeller model considered is the APC10x7 Slow Flyer and the Reynolds number of flow analyzed is approximately 68,500 (estimated at 75% radial distance) The results showed that the presence of slots have altered the performance. The presence of slots has reduced the thrust performance for the entire operational range of advance ratios. However, the power performance has increased due to decrease in torque or rotational resistance of the propeller. The efficiency is thereby increased for one model for a specific range of advance ratios. In the case of another model, for most advance ratios the efficiency was found to be decreased.