基于基元叶栅法的轴流式压气机变工况性能计算模型

Calculation Model for the Off-design Performance of an Axial-flow Compressor Based on an Elementary Cascade Method

基于基元叶栅法,建立了轴流式压气机的变工况计算模型,并采用变比热公式计算空气的热力参数;绘制了压比、等熵效率、折合耗功率和折合出口总温的通用特性曲线;计算了压气机的运行工况线。在此基础上,确定了压气机的喘振边界线。定量计算了IGV对压气机通用特性曲线的影响。建模过程中,考虑了空气相对湿度对压气机通用特性曲线的影响。算例表明,该模型精度较高,能够对具有IGV的压气机进行变工况计算。本文所做工作为进一步研究压气机的变工况性能奠定了基础。

On the basis of an elementary cascade method a calculation model for the off-design performance of an axial-flow compressor has been set up.Through the use of a variable specific-heat equation the thermodynamic parameters of air were calculated with the general characteristic curves showing pressure ratios,isentropic efficiency,corrected consumed power and outlet total temperatures being drafted and the compressor operating condition curves calculated.On this basis,the surge boundary line of the compressor was determined.A quantitative calculation of the impact of inlet guide vanes(IGV) on compressor general characteristic curves was conducted.During the model building process the influence of air relative humidity on compressor general characteristic curves has been taken into account.A calculation example indicates that the model under discussion features relative high precision and can be used to calculate the off-design performance of a compressor fitted with IGV.The work described above has laid a solid foundation for the further study of off-design performance of compressors.