基于实际运行工况的转子热力状态分析

Evaluation of Thermodynamic State of Rotor Under In-Service Operating Conditions

火电厂实际运行工况的载荷类型与过程较为多样,导致汽轮机转子的实际热力状态较难评估。以实际退役汽轮机转子为研究对象,结合该转子近10年运行历史工况,对汽轮机高中压转子的热力行为进行了全历史的有限元仿真计算,并分析了启停及降出力工况下转子的温度分布及应力行为。结果展示了蒸汽入口位置以及高压级前凹槽内温度、应力在降出力工况中的变化范围,发现当功率下降量超过100 MW时,蒸汽入口位置的温度变化最大值为51℃,应力变化范围最大值为165 MPa,需要考虑对应产生的疲劳损伤。研究成果可为高中压汽轮机的转子结构设计及运行调控提供参考。

It is difficult to evaluate the thermal state of turbine rotor because of the various load types and processes in the actual operating conditions of thermal power plant.Based on the decommissioned turbine rotor as the research objective,combining with the working condition of the rotor with a history of nearly 10 years running,the finite element simulation towards the whole history was calculated.The temperature and stress behaviors of the rotor under start-stop and down-output conditions were emphatically studied.The results displayed the variation range of the steam inlet position and the temperature and stress in the groove before the high pressure stage under the condition of power reduction.When the power reduction exceeded 100 MW,the maximum value of the temperature range reached 51℃at steam inlet position,while the stress range was 165 MPa,thus the induced fatigue damage needs to be considered.The research result can provide reference for the structure design and operation management of high-and intermediate-pressure rotors.