A Ffowcs Williams-Hawkings numerical aeroacoustic study of varied and fixed-pitch blades of an H-Rotor vertical axis wind turbineErrol Molatudi, Thokozani Justin Kunene and Lagouge Kwanda TartibuMATEC Web Conf., 347 (2021) 00013DOI: https://doi.org/10.1051/matecconf/202134700013