Effects of track parameters and environmental conditions on tramcar induced squeal noise

Rail systems noise is an area of continuing research interest. Among the different noise generation phenomena, squeal noise play an important role when dealing with tramcar operation. In fact, urban track are usually characterised by the presence of very narrow curves, which lead to a high chance of squeal. Moreover, since tramcar operate in a urban environment, near office and/or residential buildings, noise issues assume a particular relevance. The Mechanical Engineering Department has started a noise measurement and analysis program specifically concerned with the problem of tramcars squeal noise. The experience made during experimental tests and parallel numerical simulations is illustrated in this paper, whose objective consists not in providing theoretical analysis on squeal noise generation mechanism, but in pointing out some significant features of this phenomenon which are very important for understanding how to control it