Effect of the unstable vibration of the disc brake system of high-speed trains on wheel polygonalization

Abstract

This paper conducts a detailed investigation into the formation mechanism of wheel polygonalization in high-speed trains and its influence factors through numerical simulation. A finite element model including two rails, one wheelset, and three disc brake units is set up to study the formation mechanism of wheel polygonalization in high-speed trains based on the point of view of frictional self-excited vibration. Using the finite element complex analysis, the dynamic stability of the wheelset–track–disc brake system is studied. In addition, the influence factors on the wheel polygonalization are investigated. Results show that when the longitudinal creep force is unsaturated, the 21-order polygonal wear of wheels occurs easily due to the self-excited vibration of the disc brake unit. When the longitudinal creep force is saturated, the 12-order polygonal wear of wheels probably occurs due to the self-excited vibration of the disc brake unit. The bigger the friction coefficient between the brake disc and pad, the greater the occurrence propensity of the polygonal wear of wheels. Vertical fastener damping that is too large or too small is disadvantageous for suppressing wheel corrugation. However, increasing the lateral fastener damping is beneficial for reducing the polygonal wear of wheels. When the vertical fastener stiffness is 25 MN/m, 7-order, 9-order, and 14-order wheel polygonalization can easily occur. A higher lateral fastener stiffness is beneficial for the suppression of wheel polygonalization.

Polygonisation of railway wheels: a critical review

“…Kalousek and Johnson [8] (2) P2 resonance Nielsen et al [5], Johansson and Andersson [74], Tao et al [14], Li et al [17], and Cai et al [75] (3) Frictional self-excited vibration of a wheelset-track system Chen et al [76,77], Zhao et al [78], and Wu et al [79] (4) Lower bending or torsional modes of the wheelset Morys [20], Jin et al [80], Yang et al [15], Tao et al [16,[81][82][83], Fröhling et al [84], and Spangenberg [85] (5) Bending vibration modes of the rail or track Johansson and Andersson [74], Wu et al [86], Cai et al [87], Dai et al [88], and Qu et al [89] (6) Excited resonance of the bogie Wu et al [90] and Guo et al [91] (7) Vibration of other components of the bogie Ma et al [92], Liu et al [93], and Fu et al [94] 3. Thermoelastic instability Nielsen et al [5] (Summary) and Vernersson [95,96] with three harmonics.…”

“…The model was further extended to study the reason for the polygonal wear of high-speed train wheels [77,78]. Moreover, the unstable vibration of the disc brake system of high-speed trains was thought to be a possible cause of wheel polygonisation from the viewpoint of frictional self-excited vibration [79]. However, the precondition of frictional self-excited vibration is that the friction reaches saturation, which is rarely achieved in the actual operation of the train, especially for trains with distributed power and straight lines.…”

“…Although many efforts have been made to better understand the formation mechanism of wheel polygonal wear, the formation mechanism of polygonal wear of high-speed train wheels in China is still not clearly understood. However, there are three viewpoints to explain the cause of wheel polygonal wear, including an excited resonance of the bogie [90,91], a bending vibration of the rail [86][87][88][89], and frictional selfexcited vibration of the wheelset-track system [77][78][79]. Although the formation mechanism is not clear, the development of wheel polygonal wear is well controlled by using a tread cleaner, especially the new-generation highspeed EMU of the Fuxing series.…”

Dynamic Nonstationary Representations of a Railway Vehicle Considering Wheel Polygonalization under Variable Speed Conditions

“…Therefore, Tao et al [11] and Yang et al [12] applied field test and simulation methods simultaneously to study the polygon formation mechanism. Among other research, the polygonal wheel also occurs as a result of the wheelset self-excited vibration [13,14], unstable vibration of the brake disc [15], wheel flat failure [16] and other problems. Moreover, the polygonal wheel strongly affects the dynamic response of the wheel-rail interaction [17,18], especially during the curve, the impact on wheel-rail force and vehicle vibration response grown rapidly [19].…”

Effect of polygon-shaped wheels on fatigue fracture of fastener clips in high-speed railway lines

“…The potential mechanisms have been found to include the bending resonance of the wheelset, 1 track characteristics, 2 wheel material characteristics and repair operations, 3 wheelrail frictional self-excited vibration 4 and so on. [5][6][7][8] So far, there is not yet a unified theory accepted by all scholars. It is essential to suppress the impact of polygon-shaped wheels until their formation mechanism has been identified or until they can be completely eliminated.…”