Abstract: Based on wave propagation and modal superposition method, the theoretical model of sound transmission loss (STL) of a double panel structure is built. The model is validated by comparing with the diffuse STL measurements. Through the validated model, the STL properties of window on one of the high-speed train are studied. The effect of key factors on STL are also studied, namely the thickness of glass and air cavity, the damping loss factor of cavity. In order to qualify the STL of different cases, beside the weighted STL, the mass law adjustment according to the standard window are also given, which gives a reference to the lightweight design. Wheel rail noise is one of the main noise sources of high-speed train, in order to evaluate the effect of sound insulation in practice; the field wheel rail area noise is further measured at 250 km/h. The equivalent interior noise based on the STL of windows is introduced. Combine the two qualifying items, it's found that, change the ratio of the thickness of the glass of window is the most effective way to improve the STL of windows. Adding the air cavity and enlarge the damping of the cavity can also improve the STL of windows. Relative results provide indications for future low noise design of high speed train windows.

Key words: high-speed train, lightweight, low noise design, sound transmission loss, window