Aerodynamic and aeroacoustic simulations of a two-wheel landing gear

Landing gear noise is one of the dominant noise sources from an aircraft during approach phase due to low engine rate setting. Two different computational fluid dynamics (CFD) codes are used to understand the flow physics around a two-wheel main landing gear. First, flow solver for unstructured grid is used to simulate the steady-state flow field around a complex landing gear. The basic flow pattern around the landing gear is investigated and the potential noise sources, such as separation, wake and accelerated regions are observed. Additionally, the effects of the wind tunnel wall, both closed and open test sections, are investigated by including the tunnel wall in the computation. Secondly, high-order structured grid solver is used to understand the unsteady flow field on the simplified geometry. The far-field sound pressure level is evaluated using Ffowcs Williams and Hawking method. In combination, flow field around the two-wheel main landing gear will be discussed.