在线诊断中离心式压缩机预期性能计算

Calculating method for expected performance prediction in centrifugal compressor thermal performace diagnosis on line

鉴于离心式压缩机运行性能在线诊断中预期性能的计算极为重要，而对于运行中工作元件发生变化（如叶轮密封的磨损、通流各元件的结垢等）引起性能的变化尚无较好的计算方法，特别是在许多情形下压缩机的结构参数不全时更难于计算，提出将对压缩机段的热力计算简化成为一个中间平均级的计算方法；因模型简化而带来的误差引入了相应的修正系数，其值利用压缩机的性能曲线在整个性能曲线场范围内校核确定，从而推导出准确的性能参数计算式．计算示例表明，它不仅能很好地应用于压缩机运行预期性能的计算，而且能较好地应用于压缩机工作元件变化对性能影响的分析．

The expected performance of a centrifugal compressor under the operating inlet condition may be obtained by conversion from the performance under the design inlet condition on the basis of simulation theory, but the change of working elements (such as the impeller seals, filth on working elements, etc.) usually can not be taken into account. This paper presents a calculating method for the expected performance prediction, based on the average stage model of a compression stage and the correction by performance under the design condition. It can be accomplished successfully to consider the change of working elements and can be applied to the thermal performance diagnosis on line.