DOI QR코드

DOI QR Code

Analysis of the Critical Speed and Hunting Phenomenon of a High Speed Train

고속전철의 임계속도와 헌팅현상 해석

  • Song, Ki-Seok (School of Mechanical Engineering, Sungkyunkwan University) ;
  • Koo, Ja-Choon (School of Mechanical Engineering, Sungkyunkwan University) ;
  • Choi, Yeon-Sun (School of Mechanical Engineering, Sungkyunkwan University)
  • Received : 2014.08.01
  • Accepted : 2014.10.09
  • Published : 2014.10.31

Abstract

Contact between wheel and rail leads to the creep phenomenon. Linear creep theory, assuming linear increase in the creep force vs creep, results in a critical speed at which the vibration of a railway vehicle goes to infinity. However, the actual creep force converges to a limited value, so that the vibration of a railway vehicle cannot increase indefinitely. In this study, the dynamics of a railway vehicle is investigated with a 6 DOF bogie model includingthe nonlinear creep curves of Vermeulen, Polach, and a newly calculated creep curve with strip theory. Strip theory considers the profiles of the wheel and rail. The results show that the vibration of a railway vehicle results in a limit-cycle over a specific running speed, and this limit-cycle becomes smaller as the slope of the creep-curve steepens. Moreover, a hunting phenomenon is caused due to flange contact, which restricts the magnitude of the limit-cycle.

차륜과 레일의 접촉은 크리프를 유발한다. 크리프 증가에 따라 크리프력이 선형적으로 증가한다고 가정하는 선형 크리프 이론은 철도차량의 진동이 무한히 발산하는 주행속도인 임계속도를 결정한다. 그러나 실제 크리프력은 일정값에 수렴하며 철도차량의 횡진동은 무한히 증가되지도 않는다. 본 연구에서는 비선형 크리프 이론인 Vermeulen이론, Polach이론, 실제 차륜과 레일의 형상을 고려하여 계산된 줄이론 등을 6 자유도 대차모델에 적용하여 철도차량의 동특성을 검토하였다. 그 결과 철도차량의 진동은 특정 주행속도 이상에서 한계사이클을 만들었으며, 크리프 곡선의 기울기가 클수록 한계사이클이 발생하는 주행속도는 낮아졌다. 또한 한계사이클은 플랜지 접촉으로 인해 그 크기가 제한되는 헌팅현상이 발생됨을 알았다.

Keywords

References

  1. F.W. Carter (1926) On the action of a locomotive driving wheel, Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character, 112(760), pp. 151-157. https://doi.org/10.1098/rspa.1926.0100
  2. K.L. Johnson (1958) The effect of a tangential force upon the rolling motion of an elastic sphere upon a plane, Journal of Applied Mechanics, 25, pp. 339-346.
  3. K.L. Johnson, P.J. Vermeulen (1964) Contact of non-spherical bodies transmitting tangential forces, Journal of Applied Mechanics, 31, pp. 338-340. https://doi.org/10.1115/1.3629610
  4. J. Halling (1964) Microslip between a rolling element and its track arising from geometric conformity, Journal of Mechanical Engineering Science, 6, pp. 64-73. https://doi.org/10.1243/JMES_JOUR_1964_006_012_02
  5. J.J. Kalker (1967) On the rolling contact of two elastic bodies on the presence of dry friction, Ph. D. dissertation, Delft University of Technology, Delft, Netherlands.
  6. O. Polach (1999) A fast wheel-rail forces calculation computer code, Supplement to Vehicle System Dynamics, 33, pp. 728-739.
  7. T. Telliskivi, U. Olofsson (2001) Contact mechanics analysis of measured wheel-rail profiles using the finite element method, Journal of rail and rapid transit, 215(2), pp. 65-72. https://doi.org/10.1243/0954409011531404
  8. R. Enblom, M. Berg (2008) Impact of non-elliptic contact modelling in wheel wear simulation, Wear, 265(9-10), pp. 1532-1541. https://doi.org/10.1016/j.wear.2008.01.027
  9. M. Ahmadian, S. Yang (1998) Effect of system nonlinearities on locomotive bogie, Vehicle System Dynamics, 29, pp.365-384. https://doi.org/10.1080/00423119808969380
  10. S.Y. Lee, Y.C. Cheng (2005) Hunting stability analysis of highspeed railway vehicle trucks on tangent tracks, Journal of Sound and Vibration, 282, pp.881-898. https://doi.org/10.1016/j.jsv.2004.03.050
  11. Y.C. Cheng, S.Y. Lee, H.H. Chen (2009) Modeling and nonlinear hunting stability analysis of high-speed railway vehicle moving on curved tracks, Journal of Sound and Vibration, 324, pp.139-160. https://doi.org/10.1016/j.jsv.2009.01.053
  12. J.I. Cho, T.W. Park, J.W. Yoon, J.Y. Kim, Y.G. Kim (2010) Stability and safety analysis on the next generation high-speed railway vehicle, Journal of the Korean Society for Railway, 13(3), pp. 245-250.
  13. J.A. Williams (2004) Engineering tribology, Cambridge University Press, Cambridge University Press, NewYork, USA, P.419.
  14. SAMCEF 8.3 (2010) SAMTECH.
  15. MATLAB R2007B (2007) MathWorks.
  16. M. Ahmadian, S. Yang (1998) Hopf bifurcation and hunting behavior in a rail wheelset with flange contact, Nonlinear Dynamics, 15, pp. 15-30. https://doi.org/10.1023/A:1008278713331
  17. S.I. Lee, J.C. Kim, Y.S. Choi (2004) Anaylsis on the hunting motion of the KTX power car, Trans. Korean Soc. Mech. Eng. A., 28(6), pp. 755-762.