Monday  |  Salon 8  |  05:10 PM–05:30 PM

#16655–A Priori Interface Reduction using Polynomials for Structural Dynamic Analysis

A framework for reduced order modeling is proposed and demonstrated by means of storing simple substructure geometries with internal and interface reduction in a component library. The components can be translated and rotated before coupling to create a complex assembly representing a physical structure which can be used for efficient dynamic analyses. The internal degrees of freedom (DOFs) are reduced using fixed interface normal modes, and a general method for reducing the interface DOFs of a given substructure is presented by prescribing the displacements using polynomials as basis functions. The polynomials considered are divided into two groups – those which allow motion at the end point of an interface, referred to as corner polynomials, and those which solely define the displacement along the length of the interface while restricting motion at the end points, referred to as edge polynomials. Due to the interface motion being described by an identical set of basis functions on adjacent substructures, coupling along interfaces with incompatible meshes is possible without significant loss in the accuracy of dynamic properties of the assembly. The method is demonstrated on an assembly of plate-like structures showing sufficient accuracy in the prediction of the assembly’s natural frequencies and mode shapes when compared to an unreduced model.

Jon Young   Penn State
Andrew Wixom   Penn State
Rebekah Saxena   Penn State