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Theme : "AJK FED 2023" Preface Hyun Jin PARK, Shoichi MATSUDA, Chungpyo HONG Evaluation of railway vehicles' resistance against strong crosswinds and its application for safe railway operation Yayoi MISU (East Japan Railway Company) Order within Turbulence Susumu GOTO (Osaka University), Yutaro MOTOORI (Osaka University) LES/Lagrangian-particle-simulation of a Reactive Turbulent Planar Jet Jiabao Xing (Nagoya University)，Tomoaki WATANABE (Nagoya University)，and Koji NAGATA (Kyoto University) Unsteady Characteristics of Tip Leakage Vortex Cavitation in the Occurrence of Cavitation Instability in Liquid Rocket Inducer Koki TAMURA (Tohoku University)，Yuto NAKURA (Tohoku University), Satoshi KAWASAKI (Japan Aerospace Exploration Agency), Yuka IGA (Tohoku University) Water Condensation in PEMFCs at Nano-scale: Insights through Lattice DFT simulations Clint John Cortes OTIC (The University of Tokyo), Masazumi ARAO (FC-Cubic), Masashi MATSUMOTO (FC-Cubic), Hideto IMAI (FC-Cubic), Ikuya KINEFUCHI (The University of Tokyo) Reconstruction of Fluid Stress Field from Flow Birefringence using Physics-Informed Convolutional Encoder-Decoder (PICED) Daichi IGARASHI (Tokyo University of Agriculture and Technology), Shun MIYATAKE (Tokyo University of Agriculture and Technology), Jingzu YEE (Tokyo University of Agriculture and Technology), Yoshiyuki TAGAWA (Tokyo University of Agriculture and Technology) Determination of Permeability in the Volume Penalisation Method with a Smooth Mask Function Taichi TSUJIMOTO (Osaka University), Yuta NAKAO (Osaka University), Takuya TSUJI (Osaka University), Toshitsugu TANAKA (Osaka University), Kimiaki WASHINO (Osaka University)

 

Evaluation of railway vehicles' resistance against strong crosswinds and its application for safe railway operation

Abstract

Yayoi MISU East Japan Railway Company

With recent advancements in train speed, weight reduction of vehicles, and intensification of weather phenomena, ensuring the safety of trains against strong crosswinds is a critical issue in the railway field⁽¹⁾.

From a broad perspective, the basic idea of assessing the running safety of rolling stock against crosswind can be divided into "evaluation of resistance" and "evaluation of load (external force)," as shown in Figure 1. During train operation, the resistance should exceed the load.

To correctly evaluate the resistance, it is necessary to conduct wind tunnel tests that reproduce the shapes of car bodies and surrounding structures. In Japan, based on the results of past accident investigations and outdoor experiments with full-scale models, a wind tunnel test method for railroads has been proposed by Railway Technical Research Institute (RTRI) ⁽²⁾. Figure 2 shows the wind tunnel test. As shown in Figure. 3, the winds subject to aerodynamic understanding are not only the natural wind, but also the combined wind with the wind generated by the vehicle itself running, and the wind tunnel reproduces the yaw angle of the combined wind.

Using the aerodynamic forces obtained from the wind tunnel test, the critical wind speed of the vehicle is determined by considering the moments shown in Figure 4 using the equation developed by RTRI⁽³⁾.

In actual train operation, if monitored wind speeds along railway tracks are higher than the critical wind speed, trains are slowed down or suspended to prevent trains from encountering strong winds that could overturn the cars.

East Japan Railway Company has developed the necessary calcutation system⁽⁴⁾ and database⁽⁵⁾ for these evaluations and introduced a train regulation method based on the critical wind speeds determined along railway lines⁽⁶⁾. This enables the identification of weak points against strong winds and the implementation of appropriate countermeasures while improving operational stability by increasing regulation wind speeds or train running speeds at locations that have been evaluated as sufficiently resistant.

(1)	MISU, Y., “Evaluation Methods for Resistance of Railway Vehicles to Crosswinds in the World”, JREA, Vol.65, No.3 (2022), pp.45894-45897. In Japanese.
(2)	SUZUKI, M., HIBINO, Y., “Field Tests and Wind Tunnel Tests on Aerodynamic Characteristics of Train Vehicles under Crosswinds”, Quarterly Report of RTRI, 2016, Vol.57, No.1(2016) pp.55-60.
(3)	HIBINO, Y., ISHIDA, H., “Static Analysis on Railway Vehicle Overturning under Crosswind”, RTRI report, Vol.17, No.4 (2003), pp.39-44. In Japanese.
(4)	KURIHARA, Y., OYAMA, A., YASUDA, Y., "Introduction of new methods for train operation control in strong winds." JR East Technical Review 27 (2013).
(5)	MISU, Y., TAKEDA, S., DOI, K., “Establishment and Precision Improvement of Calculation System for Vehicle Overturn Resistance ​against Strong Crosswind”, Proceedings of “The fourth International Conference on Railway Technology; RAILWAYS 2018”, C9.0
(6)	HIBINO, Y., MISU, Y., KURIHARA, T., MORIYAMA, A., SHIMAMURA, M., “Study of new methods for train operation control in strong winds”, JR East Technical Review, 19, (2011).

Key words

Resistance and load, Critical wind speed, Wind tunnel test

Figures

Fig.1 Basic approach to evaluating running safety of railway vehicles against crosswinds

Fig. 2 Wind tunnel test with models of railway vehicles and viaduct (1/40 scale model)

Fig.3 Wind targeted to understand aerodynamic forces acting on a rail vehicle

Fig.4 Moments acting around the point of contact between rail and wheel on the leeward side
: Moment due to external forces like aerodynamic forces, : Moment by vehicle weight