Abstract In order to understand the dynamics of vortices on heat transfer, the unsteady flow field of tangential direction jets flowing in the annular chamber is numerically investigated by scale-adaptive simulation (SAS). The jet Reynolds number is 332,000 based on the jet’s diameter and inflow velocity for a specific geometric model. The analogy theory is used to obtain the convective heat transfer coefficient distribution on the hub surface. Spectral analysis via fast Fourier transform (FFT) is used to analyze frequency information that flows inside the chamber. The proper orthogonal decomposition (POD) method is performed on the velocity field in the chamber and the convective heat transfer coefficient on the hub surface using a snapshot method. The fast Fourier transform helps find the dominant frequency of the unsteady flow in the chamber. The time sequence of velocity fields on the radial plane shows the presence of cyclic flapping of the jet. The proper orthogonal decomposition analysis indicates that the unsteady periodic flow phenomenon in the chamber and unsteady heat transfer on the hub surface are mainly related to the dynamics of the counter-rotating vortices caused by the jet.

中文翻译：

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环形腔内圆柱面圆形切向射流非定常流动与传热的数值研究

摘要 为了解涡流在传热过程中的动力学特性，采用尺度自适应模拟（SAS）方法对环形腔内切向射流的非定常流场进行了数值研究。基于特定几何模型的射流直径和流入速度，射流雷诺数为 332,000。类比理论用于获得轮毂表面的对流传热系数分布。通过快速傅立叶变换 (FFT) 进行的频谱分析用于分析在腔室内流动的频率信息。使用快照方法对腔室内的速度场和轮毂表面的对流传热系数进行适当的正交分解 (POD) 方法。快速傅立叶变换有助于找到腔室中不稳定流动的主频率。径向平面上速度场的时间序列表明存在射流的周期性拍动。适当的正交分解分析表明，腔室内的非定常周期性流动现象和轮毂表面的非定常传热主要与射流引起的反向旋转涡流动力学有关。