Application of Viscothermal Wave Propagation Theory for Reduction of Boundary Layer Induced Noise
نویسندگان
چکیده
Boundary layer induced noise, i.e. noise inside the aircraft resulting from the turbulent boundary layer enclosing the fuselage, is known to dominate air-cabin noise at cruise conditions. In this paper a method is described to design trim panels containing a large number of coupled tubes to effectively reduce this type of noise. The theory of viscothermal wave propagation in tubes, as presented by Tijdeman [3], is discussed. To illustrate the procedure the absorption coefficient for a panel containing a number of non-coupled tubes is calculated. Initial results optimising the tubes’ length and radii for a desired fictive absorption coefficient are presented and prove the applicability of the method.
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