中文摘要：

运用模态声传递向量（MATV）方法预测现有高速列车车体铝型材在白噪声激励下的振动声辐射特性,分别对比阻尼损耗因子和铝型材结构截面三角形倾角对其振动声辐射的影响。结果显示现有高速列车车体铝型材结构在较宽频带范围内的声辐射效率随频率的提高整体呈上升趋势,最后基本趋近于1。240 Hz以下声辐射效率曲线呈近似线性递增的关系,240 Hz以上声辐射效率由于高阶模态的影响处于波动状态。铝型材阻尼损耗因子的增加可以减少铝型材结构向外辐射的噪声,阻尼损耗因子从0增加到1%,总声功率级急剧降低了约33.5 d B,随着阻尼损耗因子从3%增加到7%,总声功率级近似线性减小且降低速度放缓。铝型材截面三角形倾角越小,铝型材结构的声辐射效率越小,其辐射噪声的能力越弱,倾角从60°变化到30°,总声功率级降低了约27.9 d B。

英文摘要：

The sound radiation characteristics of section aluminum of high-speed trains were analyzed under a white noise excitation using a sound radiation prediction modal based on the modal acoustic transfer vector（MATV） method. The effects of damping loss factor and inclination angle of the interior reinforcing ribs of the section aluminum on the sound radiation properties were analyzed. It is found that for the currently used section aluminum structure in high-speed train bodies, its sound radiation efficiency increases with frequency increasing and finally approaches 1. The sound radiation efficiency increases linearly for the frequencies below 240 Hz, and fluctuates above 240 Hz. Increasing damping loss factor can result in a decrease of the noise radiated from the section aluminum structure. When the damping loss factor increases from 0 to 1 %, the overall sound power level drastically reduces by nearly 33.5 d B. When the damping loss factor increases from 3% to 7 %, the overall sound power level decreases slowly and almost linearly. It is also found that, the smaller the inclination angle of the interior reinforce ribs is, the lower the sound radiation efficiency is. The overall sound power level reduces by nearly 27.9 d B when the inclination angle changes from 60° to 30°.