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在低湍流度的均匀流场中,测量了4种圆角率(R/D=0%、5%、10%和15%)的断面宽厚比为2∶1的二维矩形柱体模型在雷诺数1.1?105≤Re≤6.8?105范围内的表面风压时程,通过对模型表面风压时程积分的方法获得了模型的气动力系数时程,分析了四个模型的气动力系数的雷诺数效应以及雷诺数对各模型的气动力系数功率谱的影响。结果表明,随着圆角率的增大,模型的平均阻力系数减小,且平均阻力系数对雷诺数越来越敏感。所有模型的均方根阻力系数和均方根升力系数都呈现明显的雷诺数效应,且模型的圆角率越大,其均方根阻力系数和均方根升力系数对雷诺数越敏感。圆角率为0%和5%模型的脉动阻力系数功率谱和脉动升力系数功率谱基本不随雷诺数而改变,但圆角率为10%和15%模型的脉动阻力系数功率谱和脉动升力系数功率谱呈现明显的雷诺数效应。此外,圆角率对断面宽厚比为2∶1的二维矩形断面模型的Strouhal数也有明显的影响。
In a uniform flow field with low turbulence, two-dimensional rectangular cylinder models with 4: 1 fillet ratio (R / D = 0%, 5%, 10% and 15% Reynolds number of 1.1? 105? Re? 6.8? 105 within the range of surface wind pressure duration, through the model surface wind pressure time-history method to obtain the model of the aerodynamic coefficient of time, analyzed the four models of the aerodynamic coefficient Reynolds number effect and Reynolds number on each model’s aerodynamic coefficient power spectrum. The results show that as the fillet rate increases, the average drag coefficient of the model decreases and the average drag coefficient becomes more and more sensitive to the Reynolds number. The root mean square drag coefficient and root mean square lift coefficient of all the models showed significant Reynolds number effects. The larger the fillet rate of the model, the more sensitive the root mean square drag coefficient and the root mean square lift coefficient to the Reynolds number. The pulsating resistance coefficient power spectrum and pulsating lift coefficient power spectrum with 0% and 5% fillet models basically did not change with the Reynolds number, but the pulsating resistance coefficient power spectrum and pulsating lift coefficient of the 10% and 15% The power spectrum shows obvious Reynolds number effect. In addition, the fillet rate also has a significant effect on the Strouhal number of a two-dimensional rectangular cross-section model with aspect ratio of 2: 1.