Department of Mechanical Engineering, Trinity College, Dublin 2, Ireland.
J Acoust Soc Am. 2013 Sep;134(3):2004-10. doi: 10.1121/1.4817913.
The noise source mechanisms involved in motorcycling include various aerodynamic sources and engine noise. The problem of noise source identification requires extensive data acquisition of a type and level that have not previously been applied. Data acquisition on track and on road are problematic due to rider safety constraints and the portability of appropriate instrumentation. One way to address this problem is the use of data from wind tunnel tests. The validity of these measurements for noise source identification must first be demonstrated. In order to achieve this extensive wind tunnel tests have been conducted and compared with the results from on-track measurements. Sound pressure levels as a function of speed were compared between on track and wind tunnel tests and were found to be comparable. Spectral conditioning techniques were applied to separate engine and wind tunnel noise from aerodynamic noise and showed that the aerodynamic components were equivalent in both cases. The spectral conditioning of on-track data showed that the contribution of engine noise to the overall noise is a function of speed and is more significant than had previously been thought. These procedures form a basis for accurate experimental measurements of motorcycle noise.
涉及摩托车的噪声源机制包括各种空气动力源和发动机噪声。噪声源识别问题需要广泛的数据采集，其类型和水平以前从未应用过。由于骑手安全限制和适当仪器的便携性，在赛道和道路上进行数据采集存在问题。解决这个问题的一种方法是使用风洞测试中的数据。这些测量值对于噪声源识别的有效性必须首先得到证明。为了实现这一目标，已经进行了广泛的风洞测试，并将其结果与赛道测量结果进行了比较。比较了赛道和风洞测试中速度与声压级的关系，发现两者相当。应用频谱调节技术将发动机噪声和风洞噪声与空气动力噪声分开，结果表明两种情况下空气动力分量是等效的。赛道数据的频谱调节表明，发动机噪声对总噪声的贡献是速度的函数，比以前认为的更为显著。这些程序为摩托车噪声的精确实验测量奠定了基础。
