屏蔽电机定子端部氮气腔温度场计算方法分析

核主泵屏蔽电机的热设计是涉及核电发展的一个关键因素,直接关系到电机能否安全运行60年。针对某屏蔽电机结构紧凑、内部损耗大,特别是氮气腔内散热条件差,定子绕组容易超温等特点,本文基于有限体积法,根据计算流体动力学(CFD)原理,分别进行了常规不考虑与考虑辐射换热两种算法时的电机内温度场数值模拟,获得了电机内的三维温度分布,并分析了定子端部氮气腔内的自然对流换热系数和热流密度等传热特性。此外,还对比了两种计算方法电机内温度分布的差异。计算结果表明,两种计算方法的峰值数值模拟结果与实验数据的相对误差分别是+3.6%、-4.2%。所得结论为对我国开发具有自主知识产权的同类电机产品具有重要参考价值。

Analysis of the Temperature Field Calculation Method of Stator End Nitrogen Chamber in the Canned Motor

The thermal design of the main pump shielding motor is a key factor relating to the development of nuclear power, which has direct influence to whether the motor can run safely for 60 years. Based on the fact that a shielded motor structure is compact, the internal loss is large, especially in the nitrogen cavity heat dissipation conditions are poor, the stator winding is easy to overheat and so on, this paper adopted the finite volume method, according to the principle of computational fluid dynamics (CFD), performed numerical simulation of the internal temperature field of the motor with and without considering radiation heat transfer, respectively. A three-dimensional temperature fields of the canned motor are obtained. And the heat transfer characteristics such as natural convective heat transfer coefficient and heat flux in the nitrogen chamber are analyzed. In addition, the differences in the temperature distribution between the two methods of the motor are compared. The result shows that the relative error of the peak temperature of winding at stator end between the numerical values of the calculation method and the experimental data is +3.6% and -4.2%, respectively. The conclusions have important reference value for the development of similar motor products with independent intellectual property rights in our country.