Calculation of the Modulus of Elasticity with Using Natural Frequency Formula and Updated Finite Element Analysis Of Automotive Rear Lamp Lens

Year 2019, Volume: 3 Issue: 2, 27 - 31, 30.06.2019

ERHAN Ay , Bariş Ediz , Taner Çal SEVDA Telli Çetin

https://doi.org/10.30939/ijastech..541253

Cited By: 2

Abstract

In this study; the weight of
the modal accelerometer used in the Roving Hammer Impact Test Method was added
in the finite element analysis (FEA) and the undamped modal analysis of the
automotive rear lamp lenses were performed. Also, calculated new Elastic Modulus
for Polymethylmethacrylate (PMMA) material with using
natural frequency formula and this value was used in the ANSYS WB program and the
undamped modal analysis was repeated. After that, frequency response functions (FRFs)
of an automotive rear lamp lens were obtained by using Roving Hammer Impact
Test Method. At the same time; dynamic characteristics of the structure,
natural frequencies, damping ratios and mode shapes were obtained. Damping
ratios were calculated from the FRF’s by using the Half Power Method. Finally, experimental modal analysis (EMA) and
FEA results were compared.

Keywords

Automotive Rear Lamp, Finite Element Analysis, Frequency Response Function (FRF), Half Power Method, Impact Hammer Test Method, Experimental Modal Analysis

References

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