CAA estimation of noise radiated from a 2D airfoil profile with leading edge high-lift devices

In the Green Regional Aircraft (GRA) project of the "Clean Sky" Joint Technology Initiative (JTI), an open rotor (OR) aircraft with 130 seats is being developed. One of the objectives in the Low Noise Conguration (LNC) domain is to reduce noise during approaching and landing phases that is annoyance perceived in the neighborhood of airports. In the landing phase, high-lift devices such as aps and slats attached to the main wing are deployed. Although this is to compensate deficiency of lift as airspeed is decreased from cruising speed, large noise is radiated from these devices. It is louder than engine noise because the power is minimum in this phase. It is very important to reduce aeroacoustic noise from these devices. This study is focused on estimation of noise radiated from a few high-lift configurations of a 2D baseline airfoil. These are equipped with a double-slotted Fowler ap at the trailing edge (TE) in common, but have different devices at the leading edge (LE). The hybrid two-step method is used for computation. In the first step, a transient ow around the airfoil is simulated using computational uid dynamics (CFD) with a model of large eddy simulation (LES)[1, 2] and time-varying pressure fluctuation on the airfoil is estimated. In the second step, sound radiation is simulated using computational aeroacoustics (CAA), where the wave equation is solved with the estimated surface pressure as a boundary condition.