一、前言对于汽轮机来说,提高机组的热效率和运行可靠性是两个基本的课题。但是,这两个课题在技术方面经常矛盾。例如,汽轮机转动部分和静止部分之间必须设置以迷宫式汽封为典型的非接触式的密封装置。在这种迷宫式汽封中,通常若增加间隙,确实可提高运行可靠性,但机组的热效率就会降低;如果减小间隙,则效果相反。为了解决这个问题,国内外科技人员进行了大量的试验研 First, the preface For the steam turbine, to improve the thermal efficiency of the unit and operational reliability are two basic topics. However, these two topics are often technologically contradictory. For example, labyrinth seals, which are typically non-contact seals, must be provided between the rotating part and the stationary part of the turbine. In such a labyrinth seal, it is usually possible to increase the operational reliability by increasing the clearance, but the thermal efficiency of the unit is reduced; if the clearance is reduced, the effect is reversed. In order to solve this problem, a large number of experimental studies have been conducted by domestic and foreign scientific and technical personnel