<b>Evaluation of the Aerodynamic Force on a Railway Vehicle in Half-bank Half-cut Line Sections</b>

Abstract

Minoru SUZUKI Yuhei NOGUCHIThe running safety of railway vehicles exposed to strong cross winds is evaluated by means of an aerodynamic coefficient obtained from wind tunnel tests. There are many types of section topography along actual railway lines, but the aerodynamic coefficient is sought for seven standard types of structure. Many lines close to the coast or rivers are often flanked by a slope on one side and a bank on the other (half-bank half-cut sections), and sections like this are treated as embankments. However, in sections with a high cut on the downwind side, the lateral aerodynamic force acting on the train is different from that in sections of normal embankments. Therefore, wind tunnel tests were conducted to obtain the aerodynamic coefficient for half-bank half-cut sections.

<b>Recent Studies on Railway Aerodynamics</b>

“…Wind tunnel tests involve the simulation of not only flat ground, but also ground structures such as bridges and embankments. Furthermore, a turbulent boundary layer that simulates the average wind speed and turbulence intensities of natural wind is used for the air flows that act on a model vehicle [1][2][3][4]. Recently, wind tunnel tests have been conducted on model vehicles that simulate several vehicle cross-sectional shapes in order to investigate the relationship between the aerodynamic force and cross-sectional shape of the vehicle.…”

<b>Recent Studies on Railway Aerodynamics and Noise</b>

“…Wind tunnel tests using this method on a series of typical vehicle shapes (five types) and track structure shapes (seven types) on conventional lines resulted in a set of summary tables of aerodynamic force coefficients [2], which have been used for evaluation of critical wind speed of overturning, a measure of vehicle resistance against cross winds. In addition to this work, studies are underway on aerodynamic force coefficients for other typical structures such as halfbanks, half-cut sections often seen on the coast [3] and structures with sound barriers or windbreak fences [4].…”