Analytical evaluation of the lifetime of a three-axle bogie frame using the analytical model validated through experimental modal analysis

The fatigue strength validation by tests of the railway bogie frames requires existence of an expensive laboratory and a long time for testing, of about 6 to 10 months. Considering these aspects, the european norms admit that fatigue tests can be replaced by finite elementes analysis, with condition that analytical model to be correctly realized and validated by tests. Experimental modal analysis provides a powerful tool for validation of the FEA model through experimental data. The article presents an application for analytical assessment of the fatigue strength for a three-axle locomotive bogie frame, before sending it to the laboratory fatigue tests. Using Ansys, it was carried out the structural analysis of the bogie frame, rezulting the modal model characterized by the modal parameters: eigenfrequencies and eigenshapes. The analytical model was validated through an EMA application carried out on the bogie frame and correlation analysis of the EMA and FEA models. The analytical model and data files containing the simulated vertical, transverse and twist loads, applied to the bogie frame according to EN13749/2011, constitutes the input data for nCode program, that evaluates the bogie frame lifetime using appropriate stress curves and a recognized hypothesis of damage accumulation.

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Use of the experimental modal analysis for analytical lifetime estimation of a bogie frame

MATEC Web of Conferences ◽

10.1051/matecconf/201817806018 ◽

2018 ◽

Vol 178 ◽

pp. 06018

Author(s):

Ion Manea ◽

Ioan Sebesan ◽

Mihai Matache ◽

Gabriel Prenta ◽

Catalin Firicel

Keyword(s):

Experimental Data ◽

Fatigue Strength ◽

Modal Analysis ◽

Analytical Model ◽

Structural Model ◽

Fatigue Tests ◽

Experimental Modal Analysis ◽

Finite Elements Analysis ◽

Interaction Forces ◽

Bogie Frame

The fatigue strength validation by tests of the railway bogie frames requires existence of an expensive laboratory and a long time for testing of about 6 to 10 months. Considering these aspects, the European norms admit that fatigue tests can be replaced by finite elements analysis (FEA), with the condition that analytical model to be correctly realized and validated by tests. Experimental modal analysis (EMA) provides a powerful tool for validation of the FEA model by experimental data. The article presents an application for assessment of the fatigue strength of a three-axle locomotive bogie frame. Using Ansys, was carried out the structural analysis of the bogie frame, resulting the modal model characterized by the modal parameters: Eigen frequencies and Eigen shapes. The analytical model was validated by an EMA application carried out on the bogie frame and correlation analysis of the EMA and FEA models. Using a special measuring wheel set, were determined the wheelrail interaction forces for various locomotive running conditions. The analytical structural model, validated through experimental data, and the data files containing the wheel-rail interaction forces, constitutes the input data for the nCode program that evaluates the bogie frame lifetime using appropriate stress curves and a recognized accumulation of damage hypothesis, e.g. the Palmgren-Miner.

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Modal-Model Applications for Large Energetic Machines

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.347.221 ◽

2007 ◽

Vol 347 ◽

pp. 221-226 ◽

Cited By ~ 1

Author(s):

Piotr Kurowski

Keyword(s):

Modal Analysis ◽

Experimental Modal Analysis ◽

Operational Modal Analysis ◽

Machine Condition ◽

Research Practice ◽

Dynamic Characterization ◽

Applied Method ◽

Modal Model ◽

Theoretical Assumptions

Modal models are commonly encountered forms of dynamic characterization of mechanical structures. They are applied in machine-condition diagnosing as well as in monitoring processes. In research practice the most frequently applied method is Experimental Modal Analysis, and in exploitation - Operational Modal Analysis. Difficulties associated with the EMA and OMA have contributed to the increase of OMAX model applications, especially in case of energetic machines. Theoretical assumptions related with modal analysis are very strong. In reality when big and heavy structures are considered often those assumptions are not fulfilled. In the paper such situations are considered and practical solutions are showed.

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Fatigue Strength and Modal Analysis of Bogie Frame for DMUs Exported to Tunisia

Journal of Applied Mathematics and Physics ◽

10.4236/jamp.2014.26041 ◽

2014 ◽

Vol 02 (06) ◽

pp. 342-348 ◽

Cited By ~ 2

Author(s):

Wei Tang ◽

Wenjing Wang ◽

Yao Wang ◽

Qiang Li

Keyword(s):

Fatigue Strength ◽

Modal Analysis ◽

Bogie Frame

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Effect of Bass Bar Tension on Modal Parameters of a Violin's Top Plate

Archives of Acoustics ◽

10.2478/aoa-2014-0015 ◽

2015 ◽

Vol 39 (1) ◽

pp. 145-149 ◽

Cited By ~ 3

Author(s):

Ewa B. Skrodzka ◽

Bogumił B.J. Linde ◽

Antoni Krupa

Keyword(s):

Modal Analysis ◽

Experimental Modal Analysis ◽

Mode Shapes ◽

Modal Parameters ◽

Normal Value ◽

Modal Damping

Abstract Experimental modal analysis of a violin with three different tensions of a bass bar has been performed. The bass bar tension is the only intentionally introduced modification of the instrument. The aim of the study was to find differences and similarities between top plate modal parameters determined by a bass bar perfectly fitting the shape of the top plate, the bass bar with a tension usually applied by luthiers (normal), and the tension higher than the normal value. In the modal analysis four signature modes are taken into account. Bass bar tension does not change the sequence of mode shapes. Changes in modal damping are insignificant. An increase in bass bar tension causes an increase in modal frequencies A0 and B(1+) and does not change the frequencies of modes CBR and B(1-).

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Damage evaluation of sandwich material on side plate hull using experimental modal analysis

Materials Today Proceedings ◽

10.1016/j.matpr.2021.04.293 ◽

2021 ◽

Author(s):

R.C. Ariesta ◽

A. Zubaydi ◽

A. Ismail ◽

T. Tuswan

Keyword(s):

Modal Analysis ◽

Experimental Modal Analysis ◽

Damage Evaluation ◽

Side Plate

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Effect of micro-notches on fatigue strength of electrodeposited nanocrystalline nickel thin films

MATEC Web of Conferences ◽

10.1051/matecconf/201816504011 ◽

2018 ◽

Vol 165 ◽

pp. 04011

Author(s):

Keisuke Tanaka ◽

Yuta Murase ◽

Hirohisa Kimachi

Keyword(s):

Thin Films ◽

Fatigue Strength ◽

Fatigue Limit ◽

Stress Ratio ◽

Fatigue Crack Initiation ◽

Fatigue Tests ◽

Fine Grained ◽

Nickel Thin Films ◽

Nano Crystalline ◽

Fictitious Crack

The effect of micro-notches on the fatigue strength of nickel thin films was studied. Two types of thin films with 10 μm thickness were produced by electrodeposition using sulfamate solution without and with brightener: ultra-fine grained film (UFG) with the grain size of 384 nm and nano-crystalline grained film (NCG) with that of 17 nm. Micro-sized notches introduced by FIB had the width of 2 μm and various depths from 8 to 150μm. Fatigue tests were conducted under the stress ratio of 0.1. The fatigue strength decreased with increasing depth of notches. NCG had much higher strength than UFG compared at the same notch depth. Notches as small as 8μm did reduce the fatigue strength of both UFG and NCG. The fatigue limit was controlled by the initiation of cracks and no non-propagating crack was observed in specimens fatigued below the fatigue limit. A model of fictitious crack successfully predicted the reduction of the fatigue limit due to micro-notches. The characteristic crack length of NCG was much smaller than the UFG, while the fatigue strength of defect-free NCG was larger than that of UFG. SEM observation of fracture surfaces was conducted to reveal micromechanisms of fatigue crack initiation.

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On the use of experimental modal analysis for system identification of a railway pantograph

International Journal of Rail Transportation ◽

10.1080/23248378.2020.1786743 ◽

2020 ◽

pp. 1-12

Author(s):

Petter Nåvik ◽

Stefano Derosa ◽

Anders Rønnquist

Keyword(s):

System Identification ◽

Modal Analysis ◽

Experimental Modal Analysis

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The Use of Modan 3D in Experimental Modal Analysis

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.486.36 ◽

2013 ◽

Vol 486 ◽

pp. 36-41 ◽

Cited By ~ 3

Author(s):

Róbert Huňady ◽

František Trebuňa ◽

Martin Hagara ◽

Martin Schrötter

Keyword(s):

Modal Analysis ◽

Vibration Analysis ◽

High Speed ◽

Mechanical Vibration ◽

Steel Sample ◽

Experimental Modal Analysis ◽

Image Correlation ◽

Optical Methods ◽

Mode Shapes ◽

Vibration Modes

Experimental modal analysis is a relatively young part of dynamics, which deals with the vibration modes identification of machines or their parts. Its development has started since the beginning of the eighties, when the computers hardware equipment has improved and the fast Fourier transform (FFT) could be used for the results determination. Nowadays it provides an uncountable set of vibration analysis possibilities starting with conventional contact transducers of acceleration and ending with modern noncontact optical methods. In this contribution we mention the use of high-speed digital image correlation by experimental determination of mode shapes and modal frequencies. The aim of our work is to create a program application called Modan 3D enabling the performing of experimental modal analysis and operational modal analysis. In this paper the experimental modal analysis of a thin steel sample performed with Q-450 Dantec Dynamics is described. In Modan 3D the experiment data were processed and the vibration modes were determined. The reached results were verified by PULSE modulus specialized for mechanical vibration analysis.

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