单级轴流氦气压气机空气模拟气动性能数值分析

HTGR-10模块式高温气冷堆作为第四代反应堆型具有系统简单、安全可靠和经济性能优越等特点。而氦气循环透平发电机组的氦气压缩机性能,将成为发电是否高效的决定因素之一。本文利用Numeca数值模拟软件对一亚音速轴流氦气压气机试验机进行了气动性能及准数关系研究,分析了气流在叶栅中的流动机理,探讨了等雷诺数下相似准数对压气机叶片性能的影响。结果表明:采用空气工质模拟氦气压缩,在马赫数小于0.4工况下对压气机的通流流动影响很小,基本可以忽略;采用大于0.5的反动度,增加正预旋可以使效率维持较高的水平;在马赫数较小的情况下,绝热指数k不会对相似模拟产生大的影响。

Numerical Simulation Analysis of the Aerodynamic Performance of a Single-stage Axial Helium Compressor with Air Serving as the Working Medium

Being the fourth generation of an advanced reactor type,HTGR-10(modular hightemperature gas cooled reactor) features a simple system,safe and reliable operation as well as high cost-effectiveness etc.Furthermore,the performance of the helium compressor in a helium circulation-based turbo-generator unit is one of the decisive factors ensuring a high efficiency of electric power generation.By using numerical simulation software NUMECA,the relationship between the aerodynamic performance and similarity criterion of a subsonic and axial helium test compressor was studied along with an analysis of the mechanism of helium flow in the cascades.An exploratory study was also performed of the impact of the similarity criterion at an equal Reynolds number on the performance of the compressor blades.The analysis of the blade aerodynamic performance has led to the conclusion that with air as a working medium being used to simulate the helium compression process,when the Mach number at this operating condition is smaller than 0.4,very little influence on the flow in the flow path of the compressor will be exercised by the Mach number.As a result,the influence in question can be basically neglected.If a reaction of more than 0.5 is employed,the increase of positive pre-whirl of the blades can maintain the efficiency at a relatively high level.Under the condition of a relatively small Mach number the adiabatic exponent k will not exercise a great influence on the similarity simulation.