Journal of Mechanical Science and Technology

The Korean Society of Mechanical Engineers (대한기계학회)
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Development of a Performance Prediction Method for Centrifugal Compressor Channel Diffusers

  • Kang, Jeong-Seek (Turbomachinery Department, Korea Aerospace Research Institute P.O.Box 113) ;
  • Cho, Sung-Kook (School of Mechanical and Aerospace Engineering, Seoul National University) ;
  • Kang, Shin-Hyoung (School of Mechanical and Aerospace Engineering, Seoul National University)
  • Published : 2002.08.01
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Abstract

A hybrid performance prediction method is proposed in the present study. A channel diffuser is divided into four subregions: vaneless space, semi-vaneless space, channel, and channel exit region. One-dimensional compressible core flow and boundary layer calculation of each region with an incidence loss model and empirical correlation of residuary pressure recovery coefficient of a channel predict the performance of diffusers. Three channel diffusers are designed and tested for validating the developed prediction method. The pressure distributions from an impeller exit to the channel diffuser exit are measured and discussed for various operating conditions from choke to nearly surge conditions. The strong non-uniform pressure distribution which is caused by impeller-diffuser interaction is obtained over the vaneless and semi-vaneless spaces. The predicted performance shows good agreement with the measured performance of diffusers at a design condition as well as at off-design conditions.

Keywords

References

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