【摘要】 为了得出车头曲面脉动压力的分布规律,利用参数变换技术,生成了高速列车车头曲面的四边形贴体网格,进而生成了高速列车头部流场的六面体网格。对车头流线型曲面的脉动压力进行了大涡模拟,得出了脉动压力的分布特性:在流场中某点处产生的压力主要影响该处本地,而对其余点的影响作用则随着距离的增加而迅速减弱;脉动压力的频带很宽,无明显的主频率。各点脉动压力的频谱在低频时幅值较大,随着频率升高,幅值以负指数规律持续下降。脉动压力1/3倍频程频谱的主要能量集中在20～500Hz频率范围内,随着列车运行速度提高,频谱的主要能量范围有向高频移动的趋势。更多还原

【Abstract】 In order to obtain the distribution rules of fluctuation pressure of train head surface,body-fitted quadrilateral and hexahedron grid was obtained of high speed train head surface based on parameter space mapping approach.The fluctuation pressure caused by streamlined curved surface of train head was calculated with LES(large eddy simulation),the distribution rules of fluctuation pressure were obtained:the fluctuation pressure is local,namely the fluctuation pressure produced at a certain point mainly affects this point,and the influence on other point weakens promptly when it is apart from this point;The frequency band of fluctuation pressure is very wide,and does not have obvious main frequency.The amplitude of fluctuation pressure is greater at low frequency.With the increase of frequency,amplitude drops continuously according to negative index law.The major energy of 1/3 octave band fluctuation pressure focuses on the frequency scope from 20 Hz to 500 Hz.With the increase of train speed,the major energy of frequency spectra has the tendency that moves to high frequency.更多还原