Study on sampling method for performance curve of centrifugal compressor

Based on the simulation data of performance of centrifugal compressor, this study analyzed the flow rate and efficiency curve of the compressor. By using third-order polynomial fitting method, we compared different results and found that the optimal sampling method was to have 5 lines of rotating speed with 7 different flow rate points in each line, in total 35 sample points, which satisfied the 5% fitting accuracy with minimal sample point and minimal experimental cost. Typical sample points for this optimal method was to set 3 lines of rotating speed and 3 flow rate points to be the maximum (rotating speed) flow rate, minimal (rotating speed) flow rate and the designed (rotating speed) flow rate, respectively. The rest sample points were distributed among those typical sample points. Finally, this sampling method was validated by the experimental results of centrifugal compressor.