Train Aerodynamics

Chapter 3

Testing techniques

Abstract

This chapter considers the range of physical testing techniques used in the study of train aerodynamics – full-scale testing and the different kinds of physical model testing. The instruments used in full-scale testing on trains and at the trackside are described, and data acquisition methods are briefly discussed. The analysis of full-scale data is then discussed, and the important concept of ensemble averaging is described. The discussion of physical model testing begins with a discussion of Reynolds number effects and then moves on to consider different types of wind tunnel simulation – low turbulence fixed ground, low turbulence moving ground and fixed ground atmospheric boundary layer simulations. The latter ...