Rotation Test of Railway Vehicle Bogie Considering Centrifugal Force Exerted at Curve Negotiation

Abstract Accurate prediction of vehicle curve negotiation performance is critically important for evaluation of railway vehicle safety. Although multibody dynamics vehicle simulation has been widely utilized for the vehicle performance evaluation, nonlinearities associated with the air suspension behavior are vastly simplified and the air mass flows of the leveling valve (LV) and differential pressure valve (DPV) are neglected in many cases. It is, however, known that changes in the air spring pressure caused by the LV and DPV make a non-negligible impact on the vertical wheel load variation and the derailment safety in small radius curved tracks. Therefore, this paper presents a numerical procedure for the analysis of the coupled vehicle and air suspension system behavior, considering nonlinearities associated with LV and DPV flow characteristics. To enable quick and accurate prediction of the history-dependent LV-induced wheel load unbalance and its impact on the derailment safety, quasi-static vehicle motion solvers for the fully coupled vehicle and air spring system flow equations are developed. Several numerical examples are presented to demonstrate the simulation capabilities developed in this study and numerical results are validated against the test data.

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Coupled single-axle running gears—a new radial steering design

Proceedings of the Institution of Mechanical Engineers Part F Journal of Rail and Rapid Transit ◽

10.1243/095440902760213620 ◽

2002 ◽

Vol 216 (3) ◽

pp. 197-206 ◽

Cited By ~ 2

Author(s):

O Polach

Keyword(s):

Design Principle ◽

Stability Limit ◽

Parameter Analysis ◽

Railway Vehicle ◽

Great Range ◽

Analysis And Design ◽

Ideal Curve ◽

The Stability ◽

Curve Negotiation

New railway vehicle concepts with broader and shorter carbodies necessitate new running gear concepts. One of the possibilities, the single-axle running gear, offers several advantages. The disadvantage of the conventional single-axle running gear during curving can be counteracted with a simple coupling between the single-axle running gears of the neighbouring carbodies. This paper presents parameter analysis and design principle of the coupled single-axle running gears. They can be constructed for an almost ideal curve negotiation in a great range of curve radii. The coupling of the running gears not only improves the running characteristics in a curve but also increases the stability limit. Bombardier Transportation Winterthur has developed the coupled single-axle running gears called FEBA. The test runs with prototype as well as with serial running gears in the Norwegian commuter train Class 72 have fully confirmed the anticipated running characteristics.

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Simulation of Low Speed Transition Curve Negotiation and Air Suspension Control to Prevent Wheel Load Reduction of Railway Vehicle

Volume 6: 5th International Conference on Multibody Systems, Nonlinear Dynamics, and Control, Parts A, B, and C ◽

10.1115/detc2005-84317 ◽

2005 ◽

Cited By ~ 1

Author(s):

Yoshihiro Suda ◽

Wenjun Wang ◽

Hisanao Komine ◽

Yoshi Sato ◽

Takuji Nakai ◽

...

Keyword(s):

Computer Simulation ◽

Control Device ◽

Transition Curve ◽

Railway Vehicle ◽

Load Reduction ◽

Air Spring ◽

Wheel Load ◽

Inner Pressure ◽

Air Suspension ◽

Curve Negotiation

This paper presents the curving performance of railway vehicles with Air Suspensions. Air Suspensions sometimes cause reduction of Wheel Load at transition curve negotiation. The axle spring of leading axle outside and air spring of leading bogie outside will extend when passing the exit transition curve because of the distortion of the track plane. Because Air Suspension has an automatic leveling function that each air spring is controlled by Leveling Valve to maintain a constant length, air in the extended spring exhaust through Leveling Valve to reduce the pressure of this air spring in order to make it back to original length. So the air spring pressure of leading bogie outside reduces furthermore and Wheel Load of leading axle outside reduces severely. This may be the reason of derailment. The distortion of track plane unbalances inner pressure of Air Suspensions and vertical load of wheels at entrance transition curve, because of the nonlinear characteristic of Air Suspension system caused by the Leveling Valve. Computer simulation of low speed transition curve negotiation shows that the lower running speed is, the more severe unbalance of Air Suspension inner pressure and Wheel Load become. The reduction of 1st axle outside wheel at exit transition curve is depended on this Wheel Load unbalance phenomena at circular curve. And this running process influences the after behavior of railway vehicle. The simulation also shows that the longer entrance transition curve is, the more severely the 1st axle outside Wheel Load reduces. The full-scale bench experiments gave the result as nearly same as computer simulation. A new concept control device is proposed to prevent the reduction of Wheel Load at exit transition curve. Both the simulation and bench experiment proved its control performance of Wheel Load reduction prevention. And proposed control device can also be used in tilting control and kneeling control of railway vehicle. General multi-body dynamics analysis software SIMPACK is used to confirm advantageous effect of proposed control device and full vehicle curve passing simulation shows that derailment coefficient reduced when proposed control device is applied in transition curve negotiation.

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