Inclusion of localized forces due to turbulent boundary layer convected pressure at junctions of coplanar structural sections

Abstract

Previous researchers showed that the concept of turbulent boundary layer (TBL) "edge forces," which are related to the convection peak of the TBL pressure wave number spectral density, is useful and important when using a finite element model to compute the bending response to TBL excitation of a plate that has a free edge. This paper examines the applicability of more general localized forces to the junction of two distinct coplanar sections that are joined along a line transverse to the flow. A formalism is developed for introducing these forces and applying them to a structure. The approach is made plausible by using two string sections as a simple structural model and showing that the sum of the localized force response and that due to the low wave number excitation matches the separately computed response corresponding to the full wave number spectral density. These localized forces can have a noticeable effect when the connection between sections is resilient.