Numerical Analysis of Railway Rolling Noise Generation

Kurzfassung

Due to its environmental and thus social relevance, railway noise has gained in the last years large importance and has been object of large legislative and normative intervention on different levels, [1, 2, 3, 4]. As a consequence, the acoustic behavior of railway vehicles is becoming a central topic for manufacturers and transportation companies, which need to developed noise optimal configurations and noise abatement concepts. This finally leads to a need for analysis tools which allow the acoustic properties of vehicles and tracks to be analyzed or predicted in an efficient and economic way, [5]. In this context, the concept of a comprehensive “acoustic management” has been developed, see for example [6]. Moreover, many standards have been defined, e.g. [7, 8, 9]. The actual rolling noise problem encompasses different topics: rail/wheel contact dynamics, wheelset and rail (partially including track) structural dynamics, sound radiation, sound propagation. An overview can be found in [10, p. 483 et seqq.]. Different established computer tools covering one of the above mentioned topics exist (e.g. SIMPACK, ANSYS, SYSNOISE, SOUNDPLAN, ...). However, some topics can still be addressed only by approximations or by the simplifying neglection of some physical effects, [10, p. 565]. This was for example the case of the structural dynamics of the rotating wheelset as a part of a complete vehicle model, which has been very recently solved, [11]. At the moment, the only commercially available software aiming to cover the whole subject of rolling noise is TWINS [12]. In the present report two aspects the overall problem are addressed: the wheel/rail contact and the structural dynamics of the wheelset. These topics cover the part of the overall problem that can be roughly designated as rolling noise generation.