Tollmien–schlichting Wave Amplitudes on a Semi–infinite Flat Plate and a Parabolic Body: Comparison of a Parabolized Stability Equation Method and Direct Numerical Simulations
نویسنده
چکیده
In this paper the interaction of free–stream acoustic waves with the leading edge of an aerodynamic body is investigated and we compare two different methods for analysing this interaction. Results are compared for a method which incorporates Orr–Sommerfeld calculations using the parabolized stability equation (PSE) to those of direct numerical simulations (DNS). By comparing the streamwise amplitude of the Tollmien–Schlichting (T–S) wave it is found that non–modal components of the boundary–layer response to an acoustic wave can persist some distance downstream of the lower branch. The effect of nose curvature on the persisting non–modal eigenmodes is also considered, with a larger nose radius allowing the non–modal eigenmodes to persist farther downstream.
منابع مشابه
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