超超临界汽轮机中压转子冷却效果分析

Analysis of the cooling efficiency of medium pressure rotor in ultrasupercritical turbine

摘要:

为了评价超超临界汽轮机中压转子的冷却效果及其对主蒸汽流动性能的影响,以600MW超超临界汽轮机中压缸为计算模型,采用气热偶合数值模拟方法对中压转子的蒸汽冷却进行了研究.计算结果表明,在所研究的冷却结构与冷却蒸汽初参数下,叶根最高与最低温度分别下降19K与95K,中压转子得到了充分冷却.冷却蒸汽增大了动叶温度分布的不均匀性,导致热应力上升.因此有冷却的动叶热应力校核应该是一个重点考虑的问题.

Abstract:

For estimating the effect of the medium pressure rotor cooling system in ultra-supercritical turbine on the main steam flow and cooling efficiency,the steam-thermo coupled numerical simulation method was used to study the medium pressure rotor steam cooling system,with the 600 MW ultra-supercritical turbine medium pressure casing as the computational model.The computational results show that the maximum and minimum temperatures of the blade root are decreased by 19 K and 95 K respectively,and the medium pressure rotor is cooled at the present cooling structure and initial parameters of the cool steam.The nonuniformity of temperature distribution of the rotation blade is increased by the cool steam,so the thermal stress is enhanced.Thus the important problem for the rotation blade to be cooled is the thermal stress verification.