Key Takeaways & Executive Findings
- •• A novel wheel-rail rolling contact model incorporating yaw angle and interfacial conditions (dry/wet) is proposed, integrating NORM and ECF algorithms for accurate normal and tangential contact solutions. • Increasing yaw angle elevates creepage, sliding area, creep force, and contact temperature, leading to higher fatigue parameter (FP) and reduced rolling contact fatigue life under both dry and wet conditions. • The fatigue life decay rate is slower under wet conditions compared to dry, highlighting the protective effect of water as a third-body layer. • The proposed framework enables more realistic fatigue life prediction for railway wheelsets, aiding in maintenance scheduling and safety assessment.
Abstract
The accuracy of wheel-rail rolling contact force is of great significance for vehicle dynamics simulation. A wheel-rail rolling contact behavior model considering wheelset yaw is proposed. The NORM algorithm is adopted to solve the wheel-rail normal contact problem. The extended creep force model (ECF) is used for the tangential contact problem, which considers different interfacial conditions, temperature in the contact area, and the elastoplastic behavior of the third body. A fatigue life prediction framework based on the critical plane method is introduced to evaluate the contact fatigue damage under the coupled influence of yaw angle and interfacial conditions. The effects of wheel yaw angle on the contact pressure and wheel-rail rolling contact fatigue life under dry and wet conditions are investigated. The results show that under both dry and wet conditions, increasing yaw angle leads to an increase in creepage, expansion of the sliding area, enhancement of creep force, and a simultaneous increase in the contact area temperature, thereby causing an increase in the fatigue parameter (FP). The wheel-rail rolling contact life with yaw angle is shortened compared to that without yaw, and the life decay rate under wet condition is slower than that under dry condition.
1. Introduction
The wheel-rail rolling contact plays a critical role in railway transportation, directly affecting train operational performance, safety, and reliability. During actual operation, the contact behavior is strongly influenced by the wheelset yaw motion [1]. Environmental conditions also notably affect wheel-rail interaction. Pollutants like rainwater, snow, or fallen leaves on the rail surface reduce the wheel-rail adhesion coefficient compared to the clean state, causing large creep [2 −4]. This, in turn, increase wear, extend braking distance, reduce traction efficiency, and affect train operation [5]. Moreover, rolling contact fatigue (RCF) failure, such as surface cracks and spalling, has emerged as a critical failure mode in wheel-rail systems, closely linked to subsurface stress distribution induced by yaw motion and interfacial conditions [6, 7].
The wheel-rail rolling contact behavior model consists of normal and tangential issues. The traditional Hertzian model has significant errors in the case of non-elliptical contacts [8]. To address this, several non-Hertzian contact models have been proposed. KALKER's CONTACT theory based on the elastic half-space assumption is one of the most effective tools for calculating non-Hertzian wheel-rail rolling contact [9]. VOLLEBREGT [10] improved CONTACT algorithm using conjugate gradients and Fourier transforms, enhancing its computational efficiency. AN et al [11] proposed an asymmetric geometric gap model with yaw angle to analyze contact geometry effects. Furthermore, a finite element model has been proposed. This model addresses the limitations of the elastic half-space, but it requires mesh discretization, thus reducing the efficiency [12]. To achieve a balance between computational accuracy and efficiency, numerous scholars have proposed various fast non-Hertzian rolling contact models based on the virtual penetration method. Common models include Kik and Piotrowski model (KP) [13], approximate surface deformation (ASD) model [14], and YANG model [15]. For yaw angle consideration, LIU et al [1] developed the extended Kik-Piotrowski (EKP) model based on the KP model, incorporating the effect of yaw angles. SUN et al [16] made further improvements on the KP model and proposed the modified Kik-Piotrowski (MKP) model. Although EKP and MKP account for yaw and maintain efficiency, the conjugate gradient-fast Fourier transform (FFT) optimized NORM algorithm achieves higher accuracy in non-elliptical contact situations.
Current tangential contact solutions include CONTACT [9], improved FASTSIM [16], and FaStrip [17], but neglect pressure/temperature effects on material elastoplasticity and interfacial conditions. MEIERHOFER et al [18] developed the ECF model via twin-disk tests, linking the third-body layer (3BL) elastoplasticity to traction characteristics. WANG et al [19] investigated wheel-rail wear considering third-body elastic-plastic behavior by co...
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LI Ding-kang, WU Bing, WANG Zhao-yang, LI Ji-peng, ZUO Jian-yong (2026). Numerical simulation of wheel-rail rolling contact fatigue considering yaw angle and interfacial conditions. Journal of Central South University. https://doi.org/10.1007/s11771-026-6210-9
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Frequently Asked Questions
What is the main contribution of this paper?
The paper proposes a numerical simulation framework for wheel-rail rolling contact fatigue that incorporates yaw angle and interfacial conditions (dry/wet), using the NORM algorithm for normal contact and the extended creep force model for tangential contact, and applies a critical plane method for fatigue life prediction.
How does yaw angle affect wheel-rail rolling contact fatigue?
Increasing yaw angle increases creepage, sliding area, creep force, and contact temperature, leading to higher fatigue parameter (FP) and reduced rolling contact fatigue life under both dry and wet conditions.
What is the effect of wet conditions on fatigue life compared to dry conditions?
Under wet conditions, the fatigue life decay rate is slower than under dry conditions, indicating that water as a third-body layer may mitigate fatigue damage to some extent.
Which algorithms are used for normal and tangential contact solutions?
The NORM algorithm (conjugate gradient-FFT optimized) is used for normal contact, and the extended creep force model (ECF) is used for tangential contact, considering interfacial conditions and elastoplastic behavior.
What is the significance of this research for railway engineering?
The research provides a more accurate prediction of wheel-rail rolling contact fatigue life, which is crucial for maintenance planning, safety assessment, and optimizing wheel-rail interface conditions to extend component life.
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