What are the effects of track flexibility on the dynamics of vehicle system, specially on wheel-rail contact behavior?
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The flexibility of the track significantly influences the dynamics of the vehicle system, particularly impacting the wheel-rail contact behavior. Track flexibility affects the wheel-rail interaction by intensifying the complexity of contact geometry on curved tracks, leading to increased dynamic effects as train speeds rise . Resilient wheels, incorporating rubber layers as spring-damper units, reduce vertical and lateral vibrations compared to solid wheels, altering the wheel-rail contact forces and carbody vibrations . Additionally, the wheel tread flat, a common fault, induces dynamic impact loads, with flexible wheelsets showing improved vertical acceleration compared to rigid wheel flats . Understanding these effects is crucial for optimizing railway dynamics, safety, and passenger comfort.
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| Papers (5) | Insight |
|---|---|
| Track flexibility affects wheel-rail contact dynamics. Flexible wheelsets improve vertical acceleration compared to rigid ones, reducing vertical impact loads. Increased flat wheel length raises hazard rate and PDF. | |
| Track flexibility influences wheel-rail contact behavior by affecting contact patch evolution, contact forces, stress/strain distribution, and axle acceleration, as discussed in the dynamic finite element simulation study. | |
| Track flexibility can influence wheel-rail contact behavior by affecting stability and ride comfort. The vehicle's dynamic response is impacted by the interaction between the vehicle and track. | |
| Track flexibility affects vehicle dynamics by influencing wheel-rail contact behavior. The enhanced wheel-rail contact model in VSI methodology considers track flexibility, enabling accurate analysis of railway dynamic applications. | |
| Resilient wheel stiffness affects wheel-rail contact behavior by reducing vertical vibration (70-300 Hz) and lateral vibration (90-300 Hz), aiming to lower contact force and carbody vibration. |
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