稳压器电加热器模型简化及抗震分析方法研究

Research of model simplifying and seismic analysis for electric heaters of the pressurizer

根据相关理论,对电加热器周围的水进行等效处理,同时根据电加热器的结构和支撑特点,研究电加热器的模型简化方法。使用有限元软件ANSYS,采用梁单元建立电加热器有限元模型,并进行模态分析和谱分析。分析结果表明:电加热器的振动频率在地震激励的主能量区间之外;电加热器在SSE地震作用下的结构强度满足要求。

Background： The electric heaters can regulate the pressure of the reactor coolant system, and are pressure boundary of the reactor coolant. The clad and sleeve of the heater are classified RCC-M class 1 and Seismic class 1I. Purpose： Model simplification and seismic analysis method of the heater are studied to support the structure design of the heater. Methods： The water around the electric heater is processed equivalently based on related theory. According to features of structure and support the finite element model of the heater is made by beam elements through finite element software ANSYS. Modal analysis and spectrum analysis for the heater are performed. Results： Analysis results are： （1） The nature vibration frequencies of the heater are respectively beyond of the frequency range which give significant values of acceleration. （2） During the SSE earthquake condition the structural strength of the heater meets the requirement. Conclusions： The seismic capability of the electric heater can be evaluated through analyzing its frequencies and stress intensity.