Wind tunnel testing on a train model subjected to crosswinds with different windbreak walls

Abstract

Crosswind stability of high-speed trains has been a prominent research topic for several decades, primarily motivated by the frequent rail-related accidents under strong crosswinds. In this study, the influence of different windbreak walls on train aerodynamic properties whilst subjected to crosswinds was assessed. The experimental campaign measured surface pressures on a stationary 1:25 model-scale of Class 390 Pendolino train under varying wind incidence angles with different windbreak walls inside a wind tunnel. For the first time, the work considers transition regions in windbreak walls, where transition regions refer to random geometrical changes in the distance between the train and the windbreak wall. Differences in pressure distribution on the train surface with and without different windbreak walls are evident. Forces on the train are calculated using the mean pressure coefficients. Overall, at a yaw angle of 90°, the tallest windbreak wall usually provided lowest mean pressure distribution on the surface of the model train due to the shielding effects; while the windbreak wall with a transition region of 90° usually produced the highest mean pressure distribution, comparatively. At a yaw angle of 30°, the results from windbreak walls with transition regions were relatively uniform indicating a smooth pressure distribution.

Influence of Posture Change on Train Running Safety under Crosswind

“…As a result, research into train aerodynamic performance and running safety in crosswinds has become popular [11][12][13]. In response to the train overturning accidents mentioned above, a large number of studies have been carried out through full-scale tests [14], scaled model tests [15][16][17], and numerical simulations [18,19] to study aerodynamic performance, the surrounding flow field distribution, the operational safety of static or dynamic trains, and the effect of wind protection facilities in crosswind regions. Among these, numerical simulation methods have received more attention in recent years [20,21] due to their reliable results, low cost, and easy control of test variables.…”

Experimental and numerical research on wind characteristics affected by actual mountain ridges and windbreaks: a case study of the Lanzhou-Xinjiang high-speed railway

“…To reduce the influence of strong crosswinds, wind barriers are commonly built because of their low costs and high effectiveness. Similarly, windbreak types and their effectiveness on bridges (Guo et al, 2015;He et al, 2019;Zhang, Gao, et al, 2013;Zhang, Xia, et al, 2013), embankments (Avila-Sanchez et al, 2010Gao & Duan, 2011) and flat ground (Hashmi et al, 2019;Yang et al, 2011;Zhang et al, 2017;Zhang, He, et al, 2019) have been studied to protect trains. In addition, due to the effects of the terrain, wind-reducing facilities are discontinuous and sometimes generate transition areas between different landforms, such as the windbreak transition induced by a regular windbreak and an open-hole tunnel or between a cutting and an embankment, bridge, or a tunnel (Deng et al, 2019;Sun et al, 2019Sun et al, , 2020Wang, 2010).…”

A numerical study of aerodynamic characteristics of a high-speed train with different rail models under crosswind

“…The impact of different end layouts of the embankment model and wall effects were analyzed by Tomasini. 7 Guo et al, 8,9 Hashmi et al 10 and Tomasini et al 11 study the effects of windbreaks and wind barriers on the train-bridge system by carrying out wind tunnel tests. A series of numerical calculations of the airflow near a high-speed train on a bridge under the crosswind was performed by Chen et al 2 Suzuki et al 12 concluded the side force coefficient of a vehicle on the low embankment was smaller than that on the high embankment.…”

“…7 Guo et al., 8,9 Hashmi et al. 10 and Tomasini et al. 11 study the effects of windbreaks and wind barriers on the train–bridge system by carrying out wind tunnel tests.…”