Propuesta metodológica para la selección y análisis del rendimiento de velas rígidas considerando condiciones aerodinámicas de pre-pérdida y post-pérdida

Abstract

The shipping industry is increasingly considering the issues

of “green shipping” and “zero-emission shipping”, which are

closely related to reducing the consumption of fossil fuels

to mitigate its environmental impact. In this way, the use of

renewable energies is increasingly perceived as part of the

energy mix, with the use of rigid sails being one of the tested

alternatives as auxiliary propulsion systems. This work studied

the analysis of the performance of rigid sails considering pre

stall and post-stall aerodynamic conditions. A methodology

was developed to obtain the aerodynamic coefficients of

the rigid sail for any position of the sail with respect to the

wind depending on the tested airfoil. Once the aerodynamic

coefficients were modelled for several angles of attack, the

thrust and overturning components generated by the sail

force on the boat were computed from before and after airfoil

stalling predictive models of the aerodynamic coefficients.

From the obtained results, the following two main conclusions

can be stated. i) The use of the sail in post-stall conditions for

higher angles of incidence (> 90°) substantially improved the

thrust generated on the boat. For the case of small incidence

angles, it is recommended to set the sail at an angle of attack

less than the airfoil stall. ii) Within the symmetrical four-digit

NACA series, the symmetrical NACA 0015 airfoil turned out to

be the best choice for geometrically defining the rigid sail cross

section.