Heat exchangers can be found in a large number of technical systems and installations. They are usually operated in combination with other machines, such as axial fans, in order to remove or supply heat to a system. The heat exchanger can influence the existing flow field and thus lead to increased noise emission from fans located downstream of the heat exchanger. This can be observed, for example, in air conditioning units in which axial fans operate in combination with heat exchangers. Even though this mechanism is known, it is not yet understood how the heat exchanger affects the sound propagation of the sound produced by the downstream machine. For example, the heat exchanger may lead to a change in directional characteristics or specific frequencies may be attenuated. In order to better understand the interaction of the heat exchanger with the sound field, sound power measurements were carried out on various heat exchangers and the sound propagation was simulated numerically. It was shown that the sound attenuation due to the interaction with the periodic tube array is detectable in heat exchangers and that this leads to a sound reduction at the Bragg frequency. Based on its filling factor, the heat exchanger can reduce the sound propagation in certain frequency bands by up to 10 dB if the geometrirical properties are selected suitably. The simulations of a single unit cell confirm in very good agreement with the experimental results. This allows the conclusion that the approach presented in this paper is a cost-effective way to model acoustic effects of heat exchangers. Furthermore, sound attenuation effects by the heat exchanger were caused by thermoviscous effects on the cooling fins and dimensions of the heat exchanger housing.

热交换器可以在大量技术系统和装置中找到。它们通常与其他机器（例如轴流风扇）结合运行，以便为系统散热或供热。热交换器会影响现有的流场，从而导致位于热交换器下游的风扇发出的噪音增加。例如，这可以在轴流风扇与热交换器结合运行的空调机组中观察到。尽管这种机制是已知的，但尚不清楚热交换器如何影响下游机器产生的声音的声音传播。例如，热交换器可能会导致方向特性的变化或特定频率可能会衰减。为了更好地了解换热器与声场的相互作用，对各种换热器进行了声功率测量，并对声传播进行了数值模拟。结果表明，由于与周期性管阵列的相互作用而导致的声音衰减在热交换器中是可检测到的，这会导致布拉格频率下的声音降低。根据其填充系数，如果几何特性选择合适，热交换器可以将某些频段的声音传播降低多达 10 dB。单个晶胞的模拟与实验结果非常吻合。由此得出的结论是，本文中提出的方法是一种模拟换热器声学效应的经济有效的方法。此外，