Eventos Anais de eventos
COBEM 2021
26th International Congress of Mechanical Engineering
Performance Analysis of Oscillating Hydrofoils with Different Wing Profiles
Submission Author:
Guilherme Amaral do Prado Campos , RJ
Co-Authors:
Guilherme Amaral do Prado Campos, Luciano Santos Constantin Raptopoulos, Max Suell Dutra
Presenter: Guilherme Amaral do Prado Campos
doi://10.26678/ABCM.COBEM2021.COB2021-1542
Abstract
The different energy converters employed in the ocean seek continuous improvement to make their operation in the world electrical matrix viable. The flapping foil is among the evolving models, which uses tidal or ocean currents to generate electrical energy. This device is inspired by the fish fins and has a harmonic motion, similar to sea life, promoting a friendly interaction with the environment. The present work developed a mathematical model validated with experiments in the literature, considering such aspects as mass and added damping, thrust, and variation of the angle of attack along the operation cycle. In the model simulations, the three symmetrical NACA profiles most used in the literature (NACA 0012, NACA 0014, and NACA 0015) were evaluated under different operating conditions, with the number of Reynolds (Re) ranging from $1.5 \times 10^{5}$ to $5.0 \times 10^{5}$. In addition, some parameters were considered constant, such as chord; arm; span; pitch and heave amplitude; maximum limit of the angle of attack (due to the restrictions of the data collected via the XFOIL algorithm, which was implemented in the modeling). This algorithm, XFOIL, generates the hydrodynamic forces of the profiles according to the number of Mach, Re and angle of attack, based on the panel method and the boundary layer theory. Therefore, this algorithm has restrictions after the hydrodynamic profile reaches the stall. Thus, limits of the angle of attack were adopted, and the model was validated with the literature. The mathematical modeling showed satisfactory results, and the simulations between the adopted symmetrical NACA profiles demonstrated gains when choosing the most appropriate model. Finally, it was found that the NACA 0015 profile is the most suitable for the Reynolds number, equal to $2.5 \times 10^{5}$ and $5.0 \times 10^{5}$ when compared to the others. In the case of Re = $1.5 \times 10^{5}$, NACA 0014 and NACA 0015 have a similar performance.
Keywords
flapping foil, oscillating hydrofoil, tidal energy, Dynamic model
