摘要
巡航状态下的机体表面噪声,其声源分为点声源和分布式声源。推进系统噪声中,风扇、压气机、核心、涡轮噪声可视为点声源,采用飞行修正的远场噪声预测方法。喷气噪声和机体噪声(机翼或尾翼后缘噪声、机身湍流边界层噪声)则为分布式声源,采用工程近场的方法进行预测。采用噪声源半经验参数关联模型,发展了巡航条件下的机体表面噪声预测计算方法。该计算方法可以对飞机机体(机身、机翼或尾翼等)外表面声场进行预测,并能够对各噪声源的辐射特性进行计算。以ARJ21—700为例:飞行高度10000m,飞行马赫数0.7,对机背表面(纵轴)5个点进行了声场预测。计算结果表明:风扇噪声是巡航条件下的最主要声源,其次为涡轮噪声、后缘噪声以及喷气混合噪声,各观察点的次要噪声源有所不同。
The noise source contain point source and distribution source insurface of airplane in cruising condition. Fan/compressor,core,turbine noise can be regarded as point source using far-field predicting method with fly forward effect. Jet noise and airframe noise （fuselage turbulence boundary layer and trailing edge） are the distribution source with the near-field method to an estimate. Semi-empirical model was used for airplane noise predicting. The method can use to predict the sound load of airplane including fuselage ,wing and tail wing and give the radiation and spectrum characteristic of the source. Taking ARJ21-700 as an example,flight level 10 000 meters and fly Mach 0.7,5 points carried on the longitudinal axis of airframe surface. The result indicates that fan noise is the primary contribution of the sound load in cruising condition the secondly one are turbine,trailing edge and jet mixing noise. For each observation point has a dissimilarity secondly source. The radiation and spectrum characteristic of different observation points was presented.
出处
《科学技术与工程》
2009年第5期1181-1186,共6页
Science Technology and Engineering
关键词
噪声预测
发动机噪声
机体噪声
近场噪声
气动声学
noise prediction engine noise fuselage noise near-field noise aeroacoustics
