Aero-engine Casings Modal Characteristic Assessment using an Efficient and Novel Modal Assurance Criterion Methodology

Abstract

— In this paper, a novel modelling methodology and experimental protocol has been proposed for a computationally efficient means of performing modal characteristic assessment while addressing the issue of spatial phase angle difference that arises in vibration analysis of axisymmetric structures. An experimental modal characteristic assessment is performed by means of a roving hammer impact test, frequency comparison, and a novel modal assurance criterion assessment methodology. The technical accuracy of the obtained vibrational characteristics is verified using simulations results based on both high fidelity and simplified FEM models. LMS software is used to perform the experimental assessment and post processing of data while MSC. PATRAN and MSC.NASTRAN are used to implement the proposed novel theory of addressing spatial phase angle differences that are associated to axisymmetric structures, such as the aero-engine casings.