Abstract

This thesis presents a method to correct for non-positive-definiteness in linear viscoelastic material functions. Viscoelastic material functions for anisotropic materials need to be interconverted in a matrix coefficient prony series form, with a requirement of positive definiteness. Fitting is usually done as a uniaxial prony series, resulting in scalar coefficients. When these uniaxial coefficients are placed in a coefficient matrix, the required positive definiteness cannot be guaranteed. For those matrices that do not meet this requirement, finding the nearest symmetric semi-positive definite form of the matrix results in a viable prony series matrix coefficient with the required positive definiteness. These corrected prony series coefficients allow for material functions to be interconverted with minimal changes to experimental data.

Thesis Completion

2020

Semester

Spring

Thesis Chair

Kwok, Kawai

Degree

Bachelor Science in Aerospace Engineering (B.S.A.E.)

College

College of Engineering and Computer Science

Department

Mechanical and Aerospace Engineering

Degree Program

Aerospace Engineering

Language

English

Access Status

Open Access

Release Date

5-1-2020

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