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Design of Unpowered Railway Vehicles
Published in Simon Iwnicki, Maksym Spiryagin, Colin Cole, Tim McSweeney, Handbook of Railway Vehicle Dynamics, 2019
Anna Orlova, Roman Savushkin, Iurii (Yury) Boronenko, Kirill Kyakk, Ekaterina Rudakova, Artem Gusev, Veronika Fedorova, Nataly Tanicheva
Modern bogie designs have a smaller number of parts in the secondary suspension and thus reduce maintenance costs. They typically use elastic elements that have a small stiffness in horizontal direction. Examples include the ETR-500 bogie (Figure 3.49), which uses Flexicoil secondary springs, and the Series E2 Shinkansen (Figure 3.50), which uses an air spring secondary suspension.
Numerical stability of co-simulation approaches to evaluate wheel profile evolution due to wear
Published in International Journal of Rail Transportation, 2020
The wheel-rail contact forces are evaluated by specific contact modules, called ‘wheel-rail pair’ in Simpack, using the FASTSIM contact algorithm. The S1002 profile is used for the wheelsets, while the UIC60 profile, canted 1:20, is adopted for the rails. The wheel-rail friction coefficient assumed for the numerical model is equal to 0.4. Each axle-box is constrained to the respective wheelset by a revolute joint, which allows only the relative rotation between the two bodies. The axle-box is connected to the bogie frame by means of two force elements: a first force element, modelled as an elastic flexicoil element, simulates the vertical and transverse stiffness of the helical spring of the primary suspension, while a second elastic element (bushing) reproduces the rubber joint connecting the axle-box control arm and bogie frame. The function of this element is to allow a yaw angle between a wheelset and a bogie frame during curve negotiation. The elastic characteristic of this element has an important influence on the wheel profile wear. The secondary suspension is simulated with flexicoil elements that simulate the vertical and transverse stiffness of the helical springs. These force elements are defined between the bolster and bogie frame. Both bolster and bogie frame are constrained with respect to the global reference system through ‘general rail-track joints’, which allow 6 degrees of freedom for each body. The coach, jointed to the main reference system with the same type of constraint, is connected to two bogie bolsters by means of two bushing elements with no rotational stiffness around the vertical z axis. The two bushings simulate the centre pivots that allow the bogie rotation with respect to the coach. The secondary suspension is completed by two lateral bumpstops that act between the bolster and the bogie frame when the lateral displacement of the bogie exceeds a certain value. The function of these elements is to limit the coach roll angle during cornering. The vehicle trailing system is simulated, on each bogie, by means of two elastic force elements acting in the longitudinal direction between the bolster and the bogie frame. The numerical model includes on each bogie two vertical dampers and two lateral dampers on the secondary suspension level. Table 2 shows the stiffness of the force elements used to build the model.