Source: https://www.researchgate.net/profile/Jean-Luc-Menet/publication/262450570_Etude_parametrique_du_comportement_aerodynamique_d'une_eolienne_a_axe_vertical_de_type_Savonius/links/00b7d537bbbe9835f6000000/Etude-parametrique-du-comportement-aerodynamique-dune-eolienne-a-axe-vertical-de-type-Savonius.pdf