ISVR Dynamics Group

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ISVR Dynamics Group

• Dr Chris Jones, ISVR
• Dr David Rhodes of Pandrol

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The group

• David Thompson Professor
• Chris Jones Reader
• Researchers
• Briony Croft Rail-head roughness growth (Corus)
• Jungsoo Ryue High frequency vibration propagation
  (BB)
• David Herron Noise from bridges (Pandrol)
• Nazirah Ahmad Improvement of a rail damper
  (TARRC)
• Zhenyu Huang Squeal noise modelling (RRUK)
• just starting
• Nuthnapa Triepaischajonsak (Tik)
• Ground vibration mitigation (SNCF, DB, SBB)
• Rebecca Broadbent Impact/rolling noise

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Major project history

• David Thompson joined ISVR in 96 from TNO
• Chris Jones joined ISVR in 97 from BR Research
• EU 4th Framework Silent Freight (96 99)
  Silent Track (97 00)
• EPSRC Ground vibration project (01 03)
• EU 5th Framework STAIRRS project
• EPSRC project on nonlinear mechanism of rolling
  noise generation (02 05)
• EU 6th Framework SILENCE (05 ..)
• EU 6th Framework INNOTRACK (06 ..)
• EPSRC project of wavenumber FE/BE methods with
  applications to railway noise
• NOEMIE project (development of noise TSIs) and
  CEN standards for rail roughness and track decay
  rates

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Modus operandi three examples for today

• Develop advanced models
• Rolling noise (TWINS)
• Generalised wavenumber FE/BE (WANDS)
• Bridge Noise (Norbert)
• Ground vibration (waFEBE)
• Apply, improve with industrial collaborators
• rail damping (Corus)
• aluminium extrusions (Bombardier)
• bridge noise (Pandrol)
• .. collaborative project on ground vibration ?
• Consultancy

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Experimental Facilities

• 36m track and bogie
• 1/5th scale rolling rig

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Rolling noiseTrack-Wheel Interaction Noise
Software
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Track and vehicle noise
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Rail damper (Corus)
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Rail damping


Measured (total sound pressures)


Predicted sound power (track only)



120
100
Sound

Sound power


pressure
level


90

110

level,

-
12

dB re 10
W
m



dB re 20
Pa


100
80


70
90


60
80


50
70














63
125
250
500
1k
2k
4k
63
125
250
500
1k
2k
4k


Frequency Hz
Frequency Hz


112.3 dB(A)
90.5 dB(A)

undamped

reference track

106.9 dB(A)

85.1 dB(A)


with absorbers
with absorber


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Implemented
Netherlands, France, Sweden, Germany

• Projects for
• improvement of elastomer
• reduced rail roughness benefit

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Aluminium extrusions (Bombardier)

• Long uniform extruded panels

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Waveguide FE and Wavedomain BE method

• Extrusions have constant geometry along x
  direction
• Structure model by Waveguide Finite Element
  (WFE)
• Fluid Wavedomain Boundary Element (WBE)

Very efficient calculations vs ordinary 3D models
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Measurements of transmission of noise
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Transmission loss
Experiment 1.5 m, calculation infinite
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Detailed analysis
Mode shape at cut-on frequency 430 Hz
Mode shape at cut-on frequency 2600 Hz
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Scanning laser velocimeter measurements
Mechanical excitation, reverberation room side
791Hz
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EngD project

• Rail fasteners and bridge noise
• student David Herron

• EngD is 4 years and differs from a PhD project
• Southampton EPSRC centre for EngD in Transport
  Engineering
• industrial partner Pandrol Ltd
• to investigate the use of special track
  components for reducing noise and vibration on
  bridges

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Norbert bridge noise modelling scheme
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Bridge Model NORBERT

• Bridge modelled as assemblage of 2400 plates

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