核电汽轮机高压缸级内凝结流动特性分析

摘要

In order to research flow characteristics and aerodynamic characteristics of wet steam in high pressure cylinder of nuclear steam turbines.Analyzing the spontaneous condensation flow of wet steam at different steam condition and working conditions by three-dimensional numerical nethod.The calculation results show that the process of spontaneous condensation of supercooled steam is the lowest,but it has the highest dynamic pressure value.Along the blade height direction,condensation firstly occurs at the upper blade,the sudden steam condensation can lead to dramatic growth of humidity.As the inlet mass flow rate decreases,the flow loss of wet steam in stage is enhanced,and the steam turbine efficiency is declined.On the premise of stable load,with steam humidity increasing at inlet,the aerodynamic performance of flow field turn worse,and the capability of work is declined.%为研究湿蒸汽在核电汽轮机高压缸内的流动特性和气动特性,对不同蒸汽状态和不同工况下湿蒸汽自发凝结流动进行三维数值分析.结果表明:过冷蒸汽自发凝结过程最缓慢,但其动压值最高.沿叶高方向,凝结首先发生在叶片上部,凝结发生的瞬间会引起湿度剧增.随着入口质量流量减小,级内湿蒸汽流动损失增加,汽轮机效率下降.在稳定负荷的前提下,随着蒸汽来流湿度增大,级内流场的气动性能变差,蒸汽的做功能力下降.