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RUTTING CORRUGATION MODELING WITH SIMPACK

C. Collette (1), H. Chollet (2), R. Bastaits (1), A. Preumont (1)(1) Department of Mechanical Engineering and Robotics, University of Brussels,

BELGIUM(2) Laboratoire des Technologies Nouvelles (LTN), Institut National de Recherche sur les

Transports et leur Sécurité, 2 av. Général Malleret-Joinville 94114 Arcueil FRANCE

Research Supported by European Commission (5th Growth Program) « Wheel-Rail Corrugation in Urban Transport »

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Contents

1. Rail Corrugation

2. The approach

3. Test Case (STIB Track Section)

4. Multi-body Model Corrugation mitigation

5. ¼ Scaled test bench

6. Conclusions & Future works

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1. Rail Corrugation

Fixing mechanism:

Resonance mode of vehicle/track system

+ same vehicles at same speed…

1st and 2nd torsional resonances of

the wheel-set

Damage Mechanism:

Plastic flow, wear, fatigue…

Wear of trough (long. Oscillations)

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Basic mechanism

A. Matsumoto Wear 253 (2002) 178-184

Rutting Corrugation

Frictional power densitydissipated in the contact patch

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2. The approach

Measurements Modeling + solutions

Scale 1:1

Validation

Scale1:4

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3. Test Case: STIB Track Section

L = 3.5 cm f = 450 Hz

L = 6 cm f = 300 Hz

L = 10 cm f = 150 Hz

L = 20 cm f = 75 Hz

L = v / f :

Mean Vehicle Speed = 16 m/s

Track Length : 710 m

Curve Radius : 175 m

L = 6 cm

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4. Multi-body model: vehicle parameters

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Multi-body model: track parameters

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Short time Fourier tranform (STFT)

2nd torsional mode

2nd bending mode1st torsional mode

Track modes

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Rutting corrugation mitigation

Dynamic Vibration absorber :

frequency ratio

optimal damping

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Rough Design (Torsion Only)

Characteristics:• Rint = 8.5 cm• Rext = 15 cm• Length = 10 cm• J = 0.5787 Kg.m2

• kT = 2.1956 106 Nm/rad• cT = 300 Nms/rad

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Full scale numerical efficiency

PSD Averaged in time (Delta - Beaulieu)

15 % mitigation15 % mitigation

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5. ¼ Scaled test bech from LTN (INRETS)

Vertical force

Verticalexcitation

Lateral forceGenerator

Rotational vibrometer Motor

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Friction law

Measurement : Simpack model : Polach approximation

Friction coefficient decreases with

important sliding velocities between the wheel and the

rail.

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Rutting corrugation: modeling

Experiment :

1. w_roller = 48.6 rad/s

2. Vertical excitation :

- Amplitude : 20 N

- Frequency : 270 Hz ( = 1st torsional mode of the wheel set)

3. T_wheelset : 3.45 Nm

4. T_roller : 5.6 Nm

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Rutting corrugation: modeling

Roll-slip phenomenon

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Rutting corrugation: measurements

Experiment : same conditions

Roll-slip phenomenon

Filtering

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6. Conclusions & Future work

Conclusions :• Complete multi-body model of the vehicle/track system• Validation with a test case (STIB metro network) :• With DVA: 15 % less energy dissipated in the contact patch.

Future work :• Parameter variation study on the scaled test bench.• Validation of the dynamic vibration absorber on the scaled test bench.