Rotor thermal stress monitoring in steam turbines

12th European Workshop on Advanced Control and Diagnosis

Antonín, Bouberle^1 ; Jan, Jakl^1 ; Jindich, Lika^1

NTIS - New Technologies for the Information Society, University of West Bohemia, Czech Republic^1

关键词: Calculation of temperature;    Heat propagation;    Machine failure;    Machine loading;    Machine operation;    Nonuniform temperature field;    Numerical solution of partial differential equations;    Stress monitoring;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/659/1/012044/pdf
DOI  :  10.1088/1742-6596/659/1/012044

来源: IOP

【 摘 要 】

One of the issues of steam turbines diagnostics is monitoring of rotor thermal stress that arises from nonuniform temperature field. The effort of steam turbine operator is to operate steam turbine in such conditions, that rotor thermal stress doesn't exceed the specified limits. If rotor thermal stress limits are exceeded for a long time during machine operation, the rotor fatigue life is shortened and this may lead to unexpected machine failure. Thermal stress plays important role during turbine cold startup, when occur the most significant differences of temperatures through rotor cross section. The temperature field can't be measured directly in the entire rotor cross section and standardly the temperature is measured by thermocouple mounted in stator part. From this reason method for numerical solution of partial differential equation of heat propagation through rotor cross section must be combined with method for calculation of temperature on rotor surface. In the first part of this article, the application of finite volume method for calculation of rotor thermal stress is described. The second part of article deals with optimal trend generation of thermal flux, that could be used for optimal machine loading.