This paper presents an analytic solution for the sound generated by an unsteady gust interacting with a semi-infinite flat plate with a serrated leading edge in a channel. The Wiener-Hopf method is used in conjunction with a non-orthogonal coordinate transformation to allow analytical progress. A solution is obtained in terms of a modal expansion, however for low- and mid-range incident frequencies only the zeroth order mode contributes to the far-field acoustics. When this is the case it is found that the modal expansion terms can be replaced by a closed-form expression that is independent of the modal expansion, allowing very quick evaluation in both the far-field and on the surface, and eliminates the possibility of Gibbs phenomenon influencing the solution. The solution gives insight into the potential mechanisms behind the reduction of noise for serrations compared with that from a straight edge.
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