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Engineering Stress, also known as Nominal Stress, is used in material testing, to quantify load carrying characteristics and abilities, such as ultimate tensile strength (UTS), modulus of rupture (under bending), yield strength, etc. Standard testing, however, is limited to regular cross-section shapes (rectangular, circle, etc.). In engineering applications, however, geometry and loading are typically much more complex. While FEA can be used to calculate local stress concentrations, the underlying Nominal Stress is not known. This paper introduces a method to calculate nominal stresses, based on FEA element nodal forces. Internal testing results of FCD500 (common material for brake components) bars, with and without notches, will be presented. Corresponding Nominal Stresses and local stress concentrations will be discussed, along with testing results.

The standard method for using FEA to predict and eliminate brake squeal has been to use complex eigenvalue analysis (CEA). Energy flow analysis has been adapted for use with FEA for brake squeal as an alternate mechanism for squeal prediction. This paper demonstrates an implementation of energy flow analysis with commercially available FEA software. The approach leverages the ability of commercial FEA solvers to obtain a quasi-static, pre-loaded brake model, as well as their eigenvalue extraction algorithms to create a modal space for energy flow calculations. The modal spaces as well as the pre-loaded stiffness matrix are then utilized to calculate energy flow values between nearby system modes. Three case studies are presented that compare the results of CEA and energy flow to different systems and countermeasures adopted to reduce noise occurrence in physical testing.