8/11/2019 ADAMS Project1

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ADAMS Project ProposalIndrasis Chakraborty

Student ID: 87441135

1 Detailed Proposal

Solid sticks are primarily made of solid lubricant in a thermosetting polymer matrix. Thissolid lm transfers to the wheel ange of the vehicle, and eventually the polymer evaporatesdue to high temperature at rail/wheel interface, results in a thin dry solid lubricant lmwhich provides low coefficient of friction ( µ ≤ 0. 1). Then this lm also transfers to the sideof the rail and nally to other railway wheels. So clearly this method of lubrication serveswell for the rail/wheel interfaces throughout the railway system.

Figure 1: Simplied model of wheel bracket assembly

Finally better understanding of friction induced self-excited vibrations such as chatterand squeal in solid stick systems is very important for designing this aforementioned solidlubrication system. And a multi-body dynamics model of the system in ADAMS will helpbetter visualising of the effect of different design parameters involved.

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8/11/2019 ADAMS Project1

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1.1 Methodology

Models of solid stick friction modier system in ADAMS will have to incorporate essentialdesign parameters. These will include, geometry and material properties of applicator-

bracket-stick assembly, angle of applicator, train speed, insert, and constant force tapespring providing the preload to the stick, and contact at the stick-wheel interface (Fig-ure ?? ). Idealized lumped parameter models is analysed in ADMAS to gain insights intothe inuence of different components. Lumped parameter models consider the interlockingsticks and applicator-bracket (Figure ?? ) as rigid objects and the exibility arises from theconstant force tape spring providing the preload and the instability arises from the inter-action of the sticks with the wheel ange contact. Frictional contact models (Coulomb,Stribeck) need to include in ADAMS for adding velocity dependence and temperaturedependence of friction coefficient along with variable normal load due to vibration.

1.2 Modelling Steps

• Import parasolid models of the applicator along with the solid stick in ADAMS.SOLIDWORKS is used for replicating models from available LB Foster’s applicatorand stick design.

• Constant force spring which pushed the stick forward is modelled in ADAMS, basedon the experimental force deection curve of the spring (existing LB Foster’s springis used for experimentation).

• Rigid rotating disc is modelled in ADAMS, which crudely replicates rotating trainwheel.

• Friction contact between the stick and wheel is used in ADAMS for studying stability

of the stick assembly.• Based on sample data from LB Foster, stick wear rate is considered. Stick mass is

taken as a time varying parameter while modelling.

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