Prescribed Velocity Method for Simulation of Aerofoil Gust Responses

A new method for modeling the interaction of an aerofoil with a gust using a prescribed velocity approach, called the split velocity method is presented. This approach effectively rearranges the governing equations into a form that allows for more efficient calculation and includes both the effect of the gust on the aerofoil and the effect of the aerofoil on the gust. The convection of gusts, through the domain from the far field, is investigated using the new method for a range of 1-cosine gusts. The results obtained are compared to an existing prescribed velocity approach called the field velocity method, which neglects the effect of the aerofoil on the gust. The two prescribed velocity approaches agree well for longer gusts. For shorter gusts where the gust length is close to the chord of the aerofoil, the new approach produces better results. Details of a linearized version of the split velocity method are also given. The linearized version is shown to agree well with the full method for cases when the gust does not result in large shock motions.