变几何多级轴流压气机全工况性能预测模型

基于压气机级的综合特性曲线,采用逐级叠加法开发了静叶可调的变几何多级轴流压气机全工况性能预测模型。在计算中将低转速下不同的级特性曲线分别应用于压气机各级,建立每一级的性能计算模块;在合理假设的基础上,根据动叶速度三角形推导出压气机入口可调静叶(IGV)角度变化对压气机性能的影响;引入气体动力学函数和变比热计算公式,简化了计算,提高了模型精度。算例表明,本模型具有一定的适用性,基本上反映出压气机的全工况特性,较准确地体现了IGV调节对整台压气机性能的影响,为开发现代大型燃气轮机动态仿真模型提供较可靠的压气机性能计算数据。

A Model for the Prediction of the Full-load-operation Performance of Variable-geometry Multi-stage Axial Compressors

Based on the comprehensive characteristic curves of compressor stages and by using a stage-by-stage superposition method,the authors have developed a model for the prediction of the full-load-operation performance of a variable geometry multistage axial compressor incorporating adjustable stationary blades.During the calculation different stage characteristic curves at a low rotating speed were used for each compressor stage to establish the performance calculation module of each stage.On the basis of rational assumptions,derived was the influence of the change in adjustable inlet guide vane(IGV) angles of the compressor on its performance based on the speed triangles of moving blades.The introduction of the aerodynamic functions and specific-heat-variable calculation formulae has simplified the calculation process,enhancing the calculation accuracy of the model.The calculation examples show that the model lends itself to practical use to a certain extent,basically reflecting the full-load-operation characteristics of the compressor and exhibiting more or less accurately the effect of IGV regulation on the performance of the whole compressor.As a result,the foregoing can well provide reliable data for the performance calculation of compressors during the development of a dynamic simulation model for modern large-sized gas turbines.