Wheel–rail contact: experimental study of the creep forces–creepage relationships

The wheel–rail contact problem plays an important role in the simulation methods used to solve railway dynamics problems. As a consequence, many different mathematical models have been developed to calculate wheel–rail contact forces. However, most of them tackle this problem purely from a theoretical point of view and need to be experimentally validated. Such validation could also reveal the influence of certain parameters not taken into account in the mathematical developments. This paper presents the steps followed in building a scaled test-bench to experimentally characterise the wheel–rail contact problem. The results of the longitudinal contact force as a function of the longitudinal creepage are obtained and the divergences with respect to Kalker's simplified theory are analysed. The influence of lateral creepage, angular velocity and certain contaminants such as cutting fluid or high positive friction modifier is also discussed

Validation of multi-body models for simulation in authorisation of rail vehicles

An application of multi-body simulations is to reduce the amount of vehicle on-track testing and present an opportunity for saving the time and costs of vehicle acceptance in regard to running characteristics. One of the objectives of the EU project DynoTRAIN was to define criteria and limits for vehicle model validation. The paper presents investigations carried out by comparing simulations with measurements from a testing campaign using a test train with 4 types of vehicles and a total of 10 force measuring wheelsets and accompanied with continuous measurement of track irregularities and rail profiles. The simulations were performed by using several vehicle models, built in different simulation tools by different partners. The results of the investigations and the criteria and limits proposed for the validation of multi-body vehicle models, intended for simulations of on-track tests, in the framework of railway vehicle authorisations are presented.Une application des simulations multi-corps consiste à réduire la quantité d'essais en ligne et à offrir une opportunité pour économiser le temps et les coûts d'acceptation des Îhicules en ce qui concerne les caractéristiques de fonctionnement dynamiques. L'un des objectifs du projet de l'UE DynoTRAIN était de définir des critères et des limites pour la validation du modèle de Îhicule. Le document présente des recherches effectuées en comparant des simulations avec des mesures à partir d'une campagne de test utilisant un train d'essai avec 4 types de Îhicules et un total de 10 essieux de mesure de force roue-rail et accompagnés d'une mesure continue des irrégularités de voie et des profils de rail. Les simulations ont été réalisées en utilisant plusieurs modèles de Îhicules, construits dans différents outils de simulation par différents partenaires. Les résultats des enquêtes et les critères et limites proposés pour la validation des modèles de Îhicules multi-corps, destinés à des simulations de tests sur voie réelle, dans le cadre des autorisations de Îhicules ferroviaires sont présentés

Dynamics of railway freight vehicles

This paper summarises the historical development of railway freight vehicles and how vehicle designers have tackled the difficult challenges of producing running gear which can accommodate the very high tare to laden mass of typical freight wagons whilst maintaining stable running at the maximum required speed and good curving performance. The most common current freight bogies are described in detail and recent improvements in techniques used to simulate the dynamic behaviour of railway vehicles are summarised and examples of how these have been used to improve freight vehicle dynamic behaviour are included. A number of recent developments and innovative components and sub systems are outlined and finally two new developments are presented in more detail: the LEILA bogie and the SUSTRAIL bogie

Study of the Falling Friction Effect on Rolling Contact Parameters

[EN] The existence of a wheel rail friction coefficient that depends on the slip velocity has been associated in the literature with important railway problems like the curving squeal and certain corrugation problems in rails. Rolling contact models that take into account this effect were carried out through the so-called Exact Theories adopting an exact elastic model of the solids in contact, and Simplified Theories which assume simplified elastic models such as Winkler. The former ones, based on Kalker s Variational Theory, give rise to numerical problems; the latter ones need to adopt hypotheses that significantly deviate from actual conditions, leading to unrealistic solutions of the contact problem. In this paper, a methodology based on Kalker s Variational Theory is presented, in which a local slip velocity-dependent friction law is considered. A formulation to get steady-state conditions of rolling contact by means of regularisation of the Coulomb s law is proposed. The model allows establishing relationships in order to estimate the global properties (creepage velocities vs. total longitudinal forces) through local properties (local slip velocity vs. coefficient of friction) or vice versa. The proposed model shows a good agreement with experimental tests while solving the numerical problems previously mentioned.The authors acknowledge the financial contribution of the Spanish Ministry of Economy and Competitiveness through the Project TRA2013-45596-C2-1-R.Giner Navarro, J.; Baeza González, LM.; Vila Tortosa, MP.; Alonso Pazos, A. (2017). Study of the Falling Friction Effect on Rolling Contact Parameters. Tribology Letters. 65(1). https://doi.org/10.1007/s11249-016-0810-8S651Grassie, S.L., Elkins, J.A.: Rail corrugation on North American transit systems. Veh. Syst. Dyn. 28, 5–17 (1998)Hsu, S.S., Huang, Z., Iwnicki, S.D., Thompson, D.J., Jones, C.J.C., Xie, G., Allen, P.D.: Experimental and theoretical investigation of railway wheel squeal. Proc. Inst. Mech. Eng. F J. Rail Rapid Transit 221, 59–73 (2007)Kalker, J.J.: Three-Dimensional Elastic Bodies in Rolling Contact. Kluwer, Dordrecht (1990)Polach, O.: Influence of locomotive tractive effort on the forces between wheel and rail. Veh. Syst. Dyn. 35, 7–22 (2001)Giménez, J.G., Alonso, A., Gómez, E.: Introduction of a friction coefficient dependent on the slip in the FastSim algorithm. Veh. Syst. Dyn. 43, 233–244 (2005)Baeza, L., Vila, P., Roda, A., Fayos, J.: Prediction of corrugation in rails using a non-stationary wheel–rail contact model. Wear 265, 1156–1162 (2008)Vollebregt, E.A.H., Schuttelaars, H.M.: Quasi-static analysis of two-dimensional rolling contact with slip-velocity dependent friction. J. Sound Vib. 331, 2141–2155 (2012)Avlonitis, M., Kalaitzidou, K., Streator, J.: Investigation of friction statics and real contact area by means a modified OFC model. Tribol. Int. 69, 168–175 (2014)Berger, E.J., Mackin, T.J.: On the walking stick–slip problem. Tribol. Int. 75, 51–60 (2014)Alonso, A., Guiral, A., Baeza, B., Iwnicki, S.D.: Wheel–rail contact: experimental study of the creep forces–creepage relationships. Veh. Syst. Dyn. 52(S1), 469–487 (2014)Spiryagin, M., Polach, O., Cole, C.: Creep force modelling for rail traction vehicles based on the Fastsim algorithm. Veh. Syst. Dyn. 51, 1765–1783 (2013)Vollebregt, E.A.H.: Numerical modeling of measured railway creep versus creep-force curves with CONTACT. Wear 314, 87–95 (2014)Kalker, J.J.: On the Rolling Contact of Two Elastic Bodies in the Presence of Dry Friction. PhD Thesis, Technical University of Delft (Holland) (1967)Baeza, L., Fuenmayor, F.J., Carballeira, J., Roda, A.: Influence of the wheel–rail contact instationary process on contact parameters. J. Strain Anal. Eng. 42, 377–387 (2007)Le Rouzic, J., Le Bot, A., Perret-Liaudet, J., Guibert, M., Rusanov, A., Douminge, L., Bretagnol, F., Mazuyer, D.: Friction-induced vibration by Stribeck’s law: application to wiper blade squeal noise. Tribol. Lett. 49, 563–572 (2013)Rabinowicz, E.: The nature of the static and kinetic coefficients of friction. J. Appl. Phys. 22, 1373–1379 (1951)Carter, F.W.: On the action of locomotive driving wheel. Proc. R. Soc. Lon. Ser. A 112, 151–157 (1926)Kalker, J.J.: A fast algorithm for the simplified theory of rolling contact. Veh. Syst. Dyn. 11, 1–13 (1982

Comparative Structural Analysis of Human DEAD-Box RNA Helicases

DEAD-box RNA helicases play various, often critical, roles in all processes where RNAs are involved. Members of this family of proteins are linked to human disease, including cancer and viral infections. DEAD-box proteins contain two conserved domains that both contribute to RNA and ATP binding. Despite recent advances the molecular details of how these enzymes convert chemical energy into RNA remodeling is unknown. We present crystal structures of the isolated DEAD-domains of human DDX2A/eIF4A1, DDX2B/eIF4A2, DDX5, DDX10/DBP4, DDX18/myc-regulated DEAD-box protein, DDX20, DDX47, DDX52/ROK1, and DDX53/CAGE, and of the helicase domains of DDX25 and DDX41. Together with prior knowledge this enables a family-wide comparative structural analysis. We propose a general mechanism for opening of the RNA binding site. This analysis also provides insights into the diversity of DExD/H- proteins, with implications for understanding the functions of individual family members

A state-of-the-art review of curve squeal noise: Phenomena, mechanisms, modelling and mitigation

[EN] Curve squeal is an intense tonal noise occurring when a rail vehicle negotiates a sharp curve. The phenomenon can be considered to be chaotic, with a widely differing likelihood of occurrence on different days or even times of day. The term curve squeal may include several different phenomena with a wide range of dominant frequencies and potentially different excitation mechanisms. This review addresses the different squeal phenomena and the approaches used to model squeal noise; both time-domain and frequency-domain approaches are discussed and compared. Supporting measurements using test rigs and field tests are also summarised. A particular aspect that is addressed is the excitation mechanism. Two mechanisms have mainly been considered in previous publications. In many early papers the squeal was supposed to be generated by the so-called falling friction characteristic in which the friction coefficient reduces with increasing sliding velocity. More recently the mode coupling mechanism has been raised as an alternative. These two mechanisms are explained and compared and the evidence for each is discussed. Finally, a short review is given of mitigation measures and some suggestions are offered for why these are not always successful.Squicciarini, G.; Thompson, D.; Ding, B.; Baeza González, LM. (2018). A state-of-the-art review of curve squeal noise: Phenomena, mechanisms, modelling and mitigation. Notes on Numerical Fluid Mechanics and Multidisciplinary Design. 139:3-41. https://doi.org/10.1007/978-3-319-73411-8_1S341139Anderson, D., Wheatley, N., Fogarty, B., Jiang, J., Howie, A., Potter, W.: Mitigation of curve squeal noise in Queensland, New South Wales and South Australia. In: Conference on Railway Engineering. pp. 625–636, Perth, Australia (2008)Hanson, D., Jiang, J., Dowdell, B., Dwight, R.: Curve squeal: causes, treatments and results. In INTER-NOISE and NOISE-CON Congress and Conference Proceedings, vol. 249, pp. 6316–6323. Melbourne, Australia (2014)Rudd, M.J.: Wheel/rail noise—part II: wheel squeal. J. Sound Vib. 46(3), 381–394 (1976)Remington, P.J.: Wheel/rail squeal and impact noise: what do we know? What don’t we know? Where do we go from here? J. Sound Vib. 116(2), 339–353 (1987)Remington, P.J.: Wheel/rail rolling noise: what do we know? What don’t we know? Where do we go from here? J. Sound Vib. 120(2), 203–226 (1988)Wickens, A.H.: Fundamentals of Rail Vehicle Dynamics, Guidance and Stability. Swets & Zeitlinger, Lisse (2003)Thompson, D.J.: Railway Noise and Vibration: Mechanisms, Modelling and Mitigation. Elsevier, Oxford (2009)Kalker, J.J.: Three Dimensional Elastic Bodies in Rolling Contact. Kluwer academic publishers, Dordrecht (1990)Vermeulen, P.J., Johnson, K.L.: Contact of nonspherical elastic bodies transmitting tangential forces. J. Appl. Mech. 31(2), 338–340 (1964)Shen, Z.Y., Hedrick, J.K., Elkins, J.A.: A comparison of alternative creep-force models for rail vehicle dynamic analysis. In: Proceedings of 8th IAVSD Symposium, Cambridge MA, Swets and Zeitlinger, Lisse, pp. 591–605 (1983)Huang, Z.Y.: Theoretical Modelling of Railway Curve Squeal. Ph.D. thesis, University of Southampton, UK (2007)Hoffmann, N., Fischer, M., Allgaier, R., Gaul, L.: A minimal model for studying properties of the mode-coupling type instability in friction induced oscillations. Mech. Res. Commun. 29(4), 197–205 (2002)Hoffmann, N., Gaul, L.: Effects of damping on mode-coupling instability in friction induced oscillations. J. Appl. Math. Mech. 83(8), 524–534 (2003)Sinou, J.J., Jezequel, L.: Mode coupling instability in friction-induced vibrations and its dependency on system parameters including damping. Eur. J. Mech.-A/Solids 26(1), 106–122 (2007)Johnson, K.L.: Contact Mechanics. Cambridge University Press, Cambridge (1985)Kinkaid, N.M., O’Reilly, O.M., Papadopoulos, P.: Automotive disc brake squeal. J. Sound Vib. 267(1), 105–166 (2003)Ghazaly, N.M., El-Sharkawy, M., Ahmed, I.: A review of automotive brake squeal mechanisms. J. Mech. Des. Vibr. 1(1), 5–9 (2013)Ouyang, H., Nack, W., Yuan, Y., Chen, F.: Numerical analysis of automotive disc brake squeal: a review. Int. J. Veh. Noise Vib. 1(3–4), 207–231 (2005)Dorf, R.C., Bishop, R.H.: Modern Control Systems, 11th edn. Prentice Hall. (2008)De Beer, F.G., Janssens, M.H.A., Kooijman, P.P., van Vliet, W.J.: Curve squeal of railbound vehicles (part 1): frequency domain calculation model. In: Proceedings of Internoise, vol. 3, pp. 1560–1563. Nice, France (2000)Von Stappenbeck, H.: Das Kurvengeräusch der Straßenbahn. Möglichkeiten zu seiner Unterdrückung. Z. VDI 96(6), 171–175 (1954)Van Ruiten, C.J.M.: Mechanism of squeal noise generated by trams. J. Sound Vib. 120(2), 245–253 (1988)Nakai, M., Chiba, Y., Yokoi, M.: Railway wheel squeal: 1st report, on frequency of squeal. Bull. Jpn. Soc. Mech. Eng. 25, 1127–1134 (1982)Nakai, M., Chiba, Y., Yokoi, M.: Railway wheel squeal: 2nd report, mechanism of specific squeal frequency. Bull. Jpn. Soc. Mech. Eng. 27, 301–308 (1984)Nakai, M., Chiba, Y., Yokoi, M.: Railway wheel squeal: 3rd report, squeal of a disk simulating a wheel in internal resonances. Bull. Jpn. Soc. Mech. Eng. 28, 500–507 (1985)Schneider, E., Popp, K., Irretier, H.: Noise generation in railway wheels due to rail-wheel contact forces. J. Sound Vib. 120(2), 227–244 (1988)Kraft, K.: Der Einfluß der Fahrgeschwindigkeit auf den Haftwert zwischen Rad und Schiene. Arch. für Eisenbahntechnik 22, 58–78 (1967)Fingberg, U.: A model of wheel-rail squealing noise. J. Sound Vib. 143(3), 365–377 (1990)Périard, F.: Wheel-Rail Noise Generation: Curve Squealing by Trams. Ph.D. thesis, Technische Universiteit Delft (1998)Heckl, M.A., Abrahams, I.D.: Curve squeal of train wheels, part 1: mathematical model for its generation. J. Sound Vib. 229(3), 669–693 (2000)Heckl, M.A.: Curve squeal of train wheels, part 2: which wheel modes are prone to squeal? J. Sound Vib. 229(3), 695–707 (2000)Heckl, M.A.: Curve squeal of train wheels: unstable modes and limit cycles. Proc. R. Soc. Lond. A: Math. Phys. Eng. Sci. 458, 1949–1965 (2002)Liu, X., Meehan, P.A.: Wheel squeal noise: a simplified model to simulate the effect of rolling speed and angle of attack. J. Sound Vib. 338, 184–198 (2015)Meehan, P.A., Liu, X.: Analytical prediction and investigation of wheel squeal amplitude. In: Anderson, D., et al. (eds.) Noise and Vibration Mitigation for Rail Transportation Systems. NNFM, vol. 139, pp 69–80. Springer, Heidelberg (2018)Kooijman, P.P., Van Vliet, W.J., Janssens, M.H.A., De Beer, F.G.: Curve squeal of railbound vehicles (part 2): set-up for measurement of creepage dependent friction coefficient. In: Proceedings of Internoise, vol. 3, pp. 1564–1567. Nice, France (2000)De Beer, F.G., Janssens, M.H.A., Kooijman, P.P.: Squeal noise of rail-bound vehicles influenced by lateral contact position. J. Sound Vib. 267(3), 497–507 (2003)Thompson, D.J., Hemsworth, B., Vincent, N.: Experimental validation of the TWINS prediction program for rolling noise, part 1: description of the model and method. J. Sound Vib. 193(1), 123–135 (1996)Monk-Steel, A., Thompson, D.J.: Models for railway curve squeal noise. In: VIII International Conference on Recent Advances in Structural Dynamics, Southampton, UK (2003)Barman, J.F., Katzenelson, J.: A generalized Nyquist-type stability criterion for multivariable feedback systems. Int. J. Control 20(4), 593–622 (1974)Huang, Z.Y., Thompson, D.J., Jones, C.J.C.: Squeal prediction for a bogied vehicle in a curve. In Schulte-Werning, B., et al. (eds.) Noise and Vibration Mitigation for Rail Transportation Systems. NNFM vol. 99, pp. 313–319. Springer, Heidelberg (2008)Hsu, S.S., Huang, Z., Iwnicki, S.D., Thompson, D.J., Jones, C.J., Xie, G., Allen, P.D.: Experimental and theoretical investigation of railway wheel squeal. Proc. Inst. Mech. Eng. Part F: J. Rail Rapid Transit 221(1), 59–73 (2007)Squicciarini, G., Usberti, S., Thompson, D.J., Corradi, R., Barbera, A.: Curve squeal in the presence of two wheel/rail contact points. In: Nielsen, J.C.O., et al. (eds.) Noise and Vibration Mitigation for Rail Transportation Systems. NNFM, vol. 126, pp. 603–610. Springer, Heidelberg (2015)Xie, G., Allen, P.D., Iwnicki, S.D., Alonso, A., Thompson, D.J., Jones, C.J., Huang, Z.Y.: Introduction of falling friction coefficients into curving calculations for studying curve squeal noise. Veh. Syst. Dyn. 44(sup1), 261–271 (2006)Giménez, J.G., Alonso, A., Gómez, E.: Introduction of a friction coefficient dependent on the slip in the FastSim algorithm. Veh. Syst. Dyn. 43(4), 233–244 (2005)Chiello, O., Ayasse, J.B., Vincent, N., Koch, J.R.: Curve squeal of urban rolling stock—part 3: theoretical model. J. Sound Vib. 293(3), 710–727 (2006)Collette, C.: Importance of the wheel vertical dynamics in the squeal noise mechanism on a scaled test bench. Shock Vibr. 19(2), 145–153 (2012)Brunel, J.F., Dufrénoy, P., Naït, M., Muñoz, J.L., Demilly, F.: Transient models for curve squeal noise. J. Sound Vib. 293(3), 758–765 (2006)Glocker, C., Cataldi-Spinola, E., Leine, R.I.: Curve squealing of trains: measurement, modelling and simulation. J. Sound Vib. 324(1), 365–386 (2009)Pieringer, A.: A numerical investigation of curve squeal in the case of constant wheel/rail friction. J. Sound Vib. 333(18), 4295–4313 (2014)Pieringer, A., Kropp, W.: A time-domain model for coupled vertical and tangential wheel/rail interaction—a contribution to the modelling of curve squeal. In: Maeda, T., et al. (eds.) Noise and Vibration Mitigation for Rail Transportation Systems. NNFM, vol. 118, pp. 221–229. Springer, Heidelberg (2012)Pieringer, A., Baeza, L., Kropp. W.: Modelling of railway curve squeal including effects of wheel rotation. In: Nielsen, J.C.O., et al. (eds.) Noise and Vibration Mitigation for Rail Transportation Systems. NNFM, vol. 126, pp. 417–424. Springer, Heidelberg (2015)Zenzerovic, I., Pieringer, A., Kropp. W.: Towards an engineering model for curve squeal. In: Nielsen, J.C.O., et al. (eds.) Noise and Vibration Mitigation for Rail Transportation Systems. NNFM, vol. 126, pp. 433–440. Springer, Heidelberg (2015)Zenzerovic, I., Kropp, W., Pieringer, A.: An engineering time-domain model for curve squeal: tangential point-contact model and Green’s functions approach. J. Sound Vib. 376, 149–165 (2016)Pieringer, A., Torstensson, P.T., Giner, J., Baeza, L.: Investigation of railway curve squeal using a combination of frequency- and time-domain models. In: Anderson, D., et al. (eds.) Noise and Vibration Mitigation for Rail Transportation Systems. NNFM, vol. 139, pp 81–93. Springer, Heidelberg (2018)Chen, G.X., Xiao, J.B., Liu, Q.Y., Zhou. Z.R.: Complex eigenvalue analysis of railway curve squeal. In: Schulte-Werning, B., et al. (eds.) Noise and Vibration Mitigation for Rail Transportation Systems. NNFM, vol. 99, pp. 433–439. Springer, Heidelberg (2008)Fourie, D.J., Gräbe, P.J., Heyns, P.S., Fröhling, R.D.: Analysis of wheel squeal due to unsteady longitudinal creepage using the complex eigenvalue method. In: Anderson, D., et al. (eds.) Noise and Vibration Mitigation for Rail Transportation Systems. NNFM, vol. 139, pp 55–67. Springer, Heidelberg (2018)Wang, C., Dwight, R., Li, W., Jiang, J.: Prediction on curve squeal in the case of constant wheel rail friction coefficient. In: Anderson, D., et al. (eds.) Noise and Vibration Mitigation for Rail Transportation Systems. NNFM, vol. 139, pp XXX–XXX. Springer, Heidelberg (2018)Ding, B., Squicciarini, G., Thompson, D.J.: Effects of rail dynamics and friction characteristics on curve squeal. In: XIII International Conference on Motion and Vibration Control and XII International Conference on Recent Advances in Structural Dynamics (MoViC/RASD), Southampton (2016)Bleedorn, T.G., Johnstone. B.: Steerable steel wheel systems and wheel noise suppression. In: Conference Rec IAS 12th Annual Meeting, Los Angeles, California (1977)Koch, J.R., Vincent, N., Chollet, H., Chiello, O.: Curve squeal of urban rolling stock—part 2: parametric study on a 1/4 scale test rig. J. Sound Vib. 293(3), 701–709 (2006)Logston, C.F., Itami, G.S.: Locomotive friction-creep studies. ASME J. Eng. Ind. 102(3), 275–281 (1980)Ertz, M.: Creep force laws for wheel/rail contact with temperature-dependent coefficient of friction. In: 8th Mini Conference on Vehicle System Dynamics, Identification and Anomalies, Budapest (2002)Lang, W., Roth, R.: Optimale Kraftschlussausnutzung bei Hochleistungs-Schienenfahrzeugen. Eisenbahntechnische Rundsch. 42, 61–66 (1993)Polach, O.: Creep forces in simulations of traction vehicles running on adhesion limit. Wear 258(7), 992–1000 (2005)Zhang, W., Chen, J., Wu, X., Jin, X.: Wheel/rail adhesion and analysis by using full scale roller rig. Wear 253(1), 82–88 (2002)Harrison, H., McCanney, T., Cotter, J.: Recent developments in coefficient of friction measurements at the rail/wheel interface. Wear 253(1), 114–123 (2002)Gallardo-Hernandez, E.A., Lewis, R.: Twin disc assessment of wheel/rail adhesion. Wear 265(9), 1309–1316 (2008)Fletcher, D.I., Lewis, S.: Creep curve measurement to support wear and adhesion modelling, using a continuously variable creep twin disc machine. Wear 298–299, 57–65 (2013)Fletcher, D.I.: A new two-dimensional model of rolling–sliding contact creep curves for a range of lubrication types. Proc. Inst. Mech. Eng. Part J: J. Eng. Tribol. 227(6), 529–537 (2013)Matsumoto, A., Sato, Y., Ono, H., Wang, Y., Yamamoto, M., Tanimoto, M., Oka, Y.: Creep force characteristics between rail and wheel on scaled model. Wear 253(1), 199–203 (2002)Janssens, M.H.A., van Vliet, W.J., Kooijman, P.P., De Beer, F.G.: Curve squeal of railbound vehicles (part 3): measurement method and results. In: Proceedings of Internoise, vol. 3, pp. 1568–1571, Nice, France (2000)Monk-Steel, A.D., Thompson, D.J., De Beer, F.G., Janssens, M.H.A.: An investigation into the influence of longitudinal creepage on railway squeal noise due to lateral creepage. J. Sound Vib. 293(3), 766–776 (2006)Liu, X., Meehan, P.A.: Investigation of the effect of lateral adhesion and rolling speed on wheel squeal noise. Proc. Inst. Mech. Eng. Part F: J. Rail Rapid Transit 227(5), 469–480 (2013)Liu, X., Meehan, P.A.: Investigation of the effect of relative humidity on lateral force in rolling contact and curve squeal. Wear 310(1), 12–19 (2014)Liu, X., Meehan, P.A.: Investigation of squeal noise under positive friction characteristics condition provided by friction modifiers. J. Sound Vib. 371, 393–405 (2016)Jie, E., Kim, J.Y., Hwang, D.H., Lee, J.H., Kim, K.J., Kim, J.C.: An experimental study of squeal noise characteristics for railways using a scale model test rig. In: J. Pombo (ed.) Proceedings of the Third International Conference on Railway Technology: Research, Development and Maintenance, Cagliari, Sardinia, Italy (2016)Eadie, D.T., Santoro, M., Kalousek, J.: Railway noise and the effect of top of rail liquid friction modifiers: changes in sound and vibration spectral distributions in curves. Wear 258(7), 1148–1155 (2005)Bullen, R., Jiang, J.: Algorithms for detection of rail wheel squeal. In: 20th International Congress on Acoustics 2010, ICA 2010—Incorporating Proceedings of the 2010 Annual Conference of the Australian Acoustical Society. pp. 2212–2216 (2010)Stefanelli, R., Dual, J., Cataldi-Spinola, E.: Acoustic modelling of railway wheels and acoustic measurements to determine involved eigenmodes in the curve squealing phenomenon. Veh. Syst. Dyn. 44(sup1), 286–295 (2006)Vincent, N., Koch, J.R., Chollet, H., Guerder, J.Y.: Curve squeal of urban rolling stock—part 1: state of the art and field measurements. J. Sound Vib. 293(3), 691–700 (2006)Anderson, D., Wheatley, N.: Mitigation of wheel squeal and flanging noise on the Australian network. In: Schulte-Werning, B., et al. (eds.) Noise and Vibration Mitigation for Rail Transportation Systems. NNFM, vol. 99, pp. 399–405. Springer, Heidelberg (2008)Curley, D., Anderson, D.C., Jiang, J., Hanson, D.: Field trials of gauge face lubrication and top-of-rail friction modification for curve noise mitigation. In: Nielsen, J.C.O., et al. (eds.) Noise and Vibration Mitigation for Rail Transportation Systems. NNFM, vol. 126, pp. 449–456. Springer, Heidelberg (2015)Jiang, J., Hanson, D., Dowdell, B.: Wheel squeal—insights from wayside condition monitoring measurements and field trials. In: Anderson, D., et al. (eds.) Noise and Vibration Mitigation for Rail Transportation Systems. NNFM, vol. 139, pp 41–53. Springer, Heidelberg (2018)Jiang, J., Dwight, R., Anderson, D.: Field verification of curving noise mechanisms. In: Maeda, T., et al. (eds.) Noise and Vibration Mitigation for Rail Transportation Systems. NNFM, vol. 118, pp. 349–356. Springer, Heidelberg (2012)Jiang, J., Anderson, D.C., Dwight, R.: The mechanisms of curve squeal. In: Nielsen, J.C.O., et al. (eds.) Noise and Vibration Mitigation for Rail Transportation Systems. NNFM, vol. 126, pp. 587–594. Springer, Heidelberg (2015)Fourie, D.J., Gräbe, P.J., Heyns, P.S., Fröhling, R.D.: Experimental characterisation of railway wheel squeal occurring in large-radius curves. Proc. Inst. Mech. Eng. Part F: J. Rail Rapid Transit 230(6), 1561–1574 (2016)Corradi, R., Crosio, P., Manzoni, S., Squicciarini, G.: Experimental investigation on squeal noise in tramway sharp curves. In: Proceedings of the 8th International Conference on Structural Dynamics, EURODYN 2011, Leuven (2011)Merideno, I., Nieto, J., Gil-Negrete, N., Landaberea, A., Iartza, J.: Constrained layer damper modelling and performance evaluation for eliminating squeal noise in trams. Shock and Vibration (2014)Nelson J.T.: Wheel/rail noise control manual, TCRP Report 23 (1997)Krüger, F.: Schall- und Erschütterungsschutz im Schienenverkehr. Expert Verlag, Renningen (2001)Elbers, F., Verheijen, E.: Railway noise technical measures catalogue, UIC report UIC003-01-04fe (2013)Oertli, J.: Combatting curve squeal, phase II, final report, UIC (2005)Eadie, D.T., Santoro, M., Powell, W.: Local control of noise and vibration with KELTRACK™ friction modifier and protector® trackside application: an integrated solution. J. Sound Vib. 267(3), 761–772 (2003)Eadie, D.T., Santoro, M.: Top-of-rail friction control for curve noise mitigation and corrugation rate reduction. J. Sound Vib. 293(3), 747–757 (2006)Suda, Y., Iwasa, T., Komine, H., Tomeoka, M., Nakazawa, H., Matsumoto, K., Nakai, T., Tanimoto, M., Kishimoto, Y.: Development of onboard friction control. Wear 258(7), 1109–1114 (2005)Bühler, S., Thallemer, B.: How to avoid squeal noise on railways: state of the art and practical experience. In: Schulte-Werning, B., et al. (eds.) Noise and Vibration Mitigation for Rail Transportation Systems. NNFM, vol. 99, pp. 406–411. Springer, Heidelberg (2008)Jones, C.J.C., Thompson, D.J.: Rolling noise generated by railway wheels with visco-elastic layers. J. Sound Vib. 231(3), 779–790 (2000)Wetta, P., Demilly, F.: Reduction of wheel squeal noise generated on curves or during braking. In 11th International of Wheelset Congress, Paris (1995)Brunel, J.F., Dufrénoy, P., Demilly, F.: Modelling of squeal noise attenuation of ring damped wheels. Appl. Acoust. 65(5), 457–471 (2004)Marjani, S.R., Younesian, D.: Suppression of train wheel squeal noise by shunted piezoelectric elements. Int. J. Struct. Stab. Dyn. (2016)Heckl, M.A., Huang, X.Y.: Curve squeal of train wheels, part 3: active control. J. Sound Vib. 229(3), 709–735 (2000)Thompson, D.J., Jones, C.J.C., Waters, T.P., Farrington, D.: A tuned damping device for reducing noise from railway track. Appl. Acoust. 68(1), 43–57 (2007)Jiang, J., Ying, I., Hanson, D., Anderson, D.C.: An investigation of the influence of track dynamics on curve noise. In: Nielsen, J.C.O., et al. (eds.) Noise and Vibration Mitigation for Rail Transportation Systems. NNFM, vol. 126, pp. 441–448. Springer, Heidelberg (2015)Toward, M., Squicciarini, G., Thompson, D.J.: Reducing freight wagon noise at source. Int. Railway J. March, 47–49 (2015)Illingworth, R., Pollard, M.G.: The use of steering axle suspensions to reduce wheel and rail wear in curves. Proc. Inst. Mech. Eng. 196(1), 379–385 (1982)Garcia, J.F., Olaizola, X., Martin, L.M., Gimenez, J.G.: Theoretical comparison between different configurations of radial and conventional bogies. Veh. Syst. Dyn. 33(4), 233–259 (2000)Bruni, S., Goodall, R., Mei, T.X., Tsunashima, H.: Control and monitoring for railway vehicle dynamics. Veh. Syst. Dyn. 45(7–8), 743–779 (2007)Hiensch, M., Larsson, P.O., Nilsson, O., Levy, D., Kapoor, A., Franklin, F., Nielsen, J., Ringsberg, J., Josefson, L.: Two-material rail development: field test results regarding rolling contact fatigue and squeal noise behaviour. Wear 258(7), 964–972 (2005)Kopp, E.: Fünf Jahre Erfahrungen mit asymmetrisch geschliffenen Schienenprofilen. Eisenbahn Techn. Rundsch. 40, 665 (1991

Creep force modelling for rail traction vehicles based on the Fastsim algorithm

The evaluation of creep forces is a complex task and their calculation is a time-consuming process for multibody simulation (MBS). A methodology of creep forces modelling at large traction creepages has been proposed by Polach [Creep forces in simulations of traction vehicles running on adhesion limit. Wear. 2005;258:992–1000; Influence of locomotive tractive effort on the forces between wheel and rail. Veh Syst Dyn. 2001(Suppl);35:7–22] adapting his previously published algorithm [Polach O. A fast wheel–rail forces calculation computer code. Veh Syst Dyn. 1999(Suppl);33:728–739]. The most common method for creep force modelling used by software packages for MBS of running dynamics is the Fastsim algorithm by Kalker [A fast algorithm for the simplified theory of rolling contact. Veh Syst Dyn. 1982;11:1–13]. However, the Fastsim code has some limitations which do not allow modelling the creep force - creep characteristic in agreement with measurements for locomotives and other highpower traction vehicles, mainly for large traction creep at low-adhesion conditions. This paper describes a newly developed methodology based on a variable contact flexibility increasing with the ratio of the slip area to the area of adhesion. This variable contact flexibility is introduced in a modification of Kalker’s code Fastsim by replacing the constant Kalker’s reduction factor, widely used in MBS, by a variable reduction factor together with a slip-velocity-dependent friction coefficient decreasing with increasing global creepage. The proposed methodology is presented in this work and compared with measurements for different locomotives. The modification allows use of the well recognised Fastsim code for simulation of creep forces at large creepages in agreement with measurements without modifying the proven modelling methodology at small creepages