<p>To predict the effect of inlet total pressure distortion on a two-stage high-speed axial fan with less computational costs, a three-dimensional body-force model (BFM) is developed. To capture the circumferential interaction of each sector under distortion condition, the governing equation of BFM is derived based on the time average operator. A correction factor is added to BFM to account for the effect of induced swirl, which is vital for simulating of coupling effect between distorted inflow and fan. Further, steady simulations with and without an inserted baffle distortion generator are performed using BFM, and the obtained distorted compressor characteristics are compared with the full-annulus Unsteady Reynolds-averaged Navier-Stokes (URANS) and experiment results. It is shown that the BFM can simulate the pressurization effect of each blade row on airflow and its deflection capability in the radial direction under uniform condition. The transfer of distorted characteristics insides the two-stage fan captured by BFM match well with URANS and experiment. The changes of blade loading with and without distortion are in line with URANS. After the airflow goes through the fan, the total temperature distortion would be induced. In addition, the intensity of total pressure distortion is weakened. Conversely, the intensity of total temperature distortion is enhanced, and the total temperature and static entropy at the blade tip region after turning out of the corresponding distortion baffle are more significant. All above-mentioned results demonstrate the BFM can significantly reduce the consumption of computing resources while effectively capture the main flow features inside fan.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

Performance Prediction of a Two-Stage High-Speed Axial Fan with Total Pressure Distorted Inflow Based on Body-Force Model

  • Jiahui Qiu,
  • Min Zhang,
  • Zihao Zhu,
  • Juan Du,
  • Penghao Duan

摘要

To predict the effect of inlet total pressure distortion on a two-stage high-speed axial fan with less computational costs, a three-dimensional body-force model (BFM) is developed. To capture the circumferential interaction of each sector under distortion condition, the governing equation of BFM is derived based on the time average operator. A correction factor is added to BFM to account for the effect of induced swirl, which is vital for simulating of coupling effect between distorted inflow and fan. Further, steady simulations with and without an inserted baffle distortion generator are performed using BFM, and the obtained distorted compressor characteristics are compared with the full-annulus Unsteady Reynolds-averaged Navier-Stokes (URANS) and experiment results. It is shown that the BFM can simulate the pressurization effect of each blade row on airflow and its deflection capability in the radial direction under uniform condition. The transfer of distorted characteristics insides the two-stage fan captured by BFM match well with URANS and experiment. The changes of blade loading with and without distortion are in line with URANS. After the airflow goes through the fan, the total temperature distortion would be induced. In addition, the intensity of total pressure distortion is weakened. Conversely, the intensity of total temperature distortion is enhanced, and the total temperature and static entropy at the blade tip region after turning out of the corresponding distortion baffle are more significant. All above-mentioned results demonstrate the BFM can significantly reduce the consumption of computing resources while effectively capture the main flow features inside fan.