US Patent 10196897 Fan exit guide vane platform contouring

A turbofan engine includes a fan section with a plurality of fan blades rotatable about an engine axis generating an airflow, a bypass passage through which the airflow passes, and a fan exit guide vane. The fan exit guide vane assembly includes a plurality of airfoils disposed between an inner platform wall and an outer platform wall. At least one of the inner platform wall and the outer platform wall includes a contoured surface between adjacent airfoils. The contoured surface includes at least one concave region and at least one convex region. A method of reducing secondary flow structures in bypass air flow with the turbofan is also disclosed.