Sound transmission through a high-speed train roof

• Low internal noise in train carriages is of great importance to the comfort of the passengers, and accordingly also for train manufacturers and operators who want to keep a comfort advantage in relation to other means of transportation. With increased speed the aerodynamic noise becomes an important contributor. Here a train roof section is studied containing a recess where a pantograph is mounted. Significant excitation is present both from aerodynamic forces directly acting on the roof as well as forces transmitted via the pantograph structure and the power input to the compartment is studied for speeds up to 350 km/h. The train roof was modeled using a hybrid FE-SEA approach with input excitation data from transient and compressible CFD calculations as well as from measured structural forces from a full scale wind tunnel test. For reference, turbulent boundary layer (TBL) excitation was studied using a Corcos model. For the transmission model the outer roof structure is described by FE whereas the interior parts are represented by statistical subsystems. Experimental validation of the approach was made on an existing train. The result indicates that for the configuration and sources analysed the contributions to the interior noise from all three sources analysed are significant. Ranking of transmission paths into the train interior and perspectives for application of such models for parametric studies of design parameters are discussed.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Maskinteknik -- Farkostteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Mechanical Engineering -- Vehicle Engineering (hsv//eng)

Keyword

A-train

Aerodynamic forces

Aerodynamic noise

Corcos model

Design parameters

Experimental validations

Full scale

High speed trains

Interior noise

Internal noise

Parametric study

Power input

Roof section

Roof structures

Sound transmission

Structural forces

Train carriage

Train interiors

Transmission model

Transmission paths

Turbulent boundary layers

Wind tunnel tests

Acoustic noise

Aerodynamics

Automobile manufacture

Pantographs

Roofs

Publication and Content Type

ref (subject category)

kon (subject category)