Aeroacoustic Scaling of a Compressor Stator Blade Row

在过去的几十年里，对现代涡喷发动机的叶轮机械部件施加的经济和监管要求变得更加严格。因此，在早期开发阶段考虑噪声排放正成为越来越重要的设计标准。在工业中，应用于此目的的建模通常基于分析或经验方法，这些方法假定将叶片排抽象为平板。这些模型的验证以及后期设计阶段基于实验参考数据的数值工具的验证是复杂的，因为由于声学上不合适的边界条件(低信噪比，测量段内的声反射高)，普通的叶轮机械试验台不能用于高质量的声学测量。另一方面，声学优化的试验台仅在选定的设计和配置中可用。对于这些声学试验台的使用，必须进行相似性评估，以便在声学边界条件可控的情况下对真实机器和试验台环境进行比较。为了实现这种气动声学相似性，基于解析方法的方法已经存在，但到目前为止，它们只用简化的数值方法进行验证。因此，该项目的目的是扩大现有的比例方法，并在广泛的数值和实验调查中对其进行验证。作为实际应用，建立并研究了高速轴流压气机静叶排与TFD声学风洞的气动声学相似性。在高精度测量和数值模拟的基础上，将对定标方法进行验证，以便更容易地将实验声学研究转移到航空发动机和固定叶轮机械。

Economic and regulatory requirements imposed on turbomachinery components of modern turbojet engines have been becoming more stringent over the last decades. The consideration of noise emissions in early development stages is thus becoming an increasingly important design criterion. In the industry, the modelling applied for this purpose is usually based on analytical or empirical approaches, which assume an abstraction of the blade rows, e.g. as flat plates. The validation of these models, but also of numerical tools in later design stages, based on experimental reference data is complicated by the fact that the common turbomachinery test rigs cannot be used for high-quality acoustic measurements due to acoustically unsuitable boundary conditions (low signal-to-noise ratio, high acoustic reflections within the measuring section).On the other hand, acoustically optimized test rigs are only available in selected designs and configurations. For the use of these acoustic test rigs, a similarity assessment is necessary, which allows a comparison between real machines and the test rig environments with controllable acoustic boundary conditions. To achieve this aeroacoustic similarity, approaches based on analytical methods already exist, but so far, they have only been validated with simplified numerical methods. The aim of the project is therefore to extend an existing scaling approaches and to validate them in extensive numerical and experimental investigations. As a practical application, the aeroacoustic similarity of a stator blade row between the high-speed axial compressor and the acoustic wind tunnel of the TFD will be established and investigated. Based on the high-precision measurements and numerical simulations, the validation of the scaling approach will be carried out in order to enable an easier transfer of experimental acoustic investigations to aero engines and stationary turbomachinery in the long term.