﻿ 双水内冷调相机转子线圈强励温升数值模拟
 上海理工大学学报  2019, Vol. 41 Issue (5): 492-497 PDF

1. 上海电气电站设备有限公司 发电机厂技术部，上海 200240;
2. 上海理工大学 能源与动力工程学院，上海 200093

Numerical Simulation on Rotor Winding Temperature Rise under Forced Excitation of Double Water Inner Cooled Condenser
XIAN Zhelong1, ZHANG Xiaohu1, HU Lei1, WANG Lei1, WANG Tingshan1, YUAN Yichao2
1. Design Department, Generator Plant, Shanghai Electric Power Generation Equipment Co., Ltd. Shanghai 200240;
2. School of Energy and Power Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
Abstract: To analyze the forced excitation capability of double water inner cooled condenser, three-dimensional numerical simulation was carried out to study the rotor winding temperature rise under forced excitation by using Fluent software. A three-dimensional model of the rotor winding was build according to its actual size, and the transient temperature distributions of cooper and water in the rotor winding under forced excitation by grids division and governing equations solution. Finally, the result was compared with that from the one-dimensional approximate calculation, the shortcomings of the traditional one-dimensional approximate calculation method were pointed out. The results show that the three-dimensional numerical simulation provides a higher accuracy. The research has an important guiding significance for the theoretical calculation of transient temperature rise and the design to the temperature margin in rotor winding of double water inner cooled condenser.
Key words: double water inner cooled     condenser     forced excitation     three-dimentional numerical simulation

1 转子线圈冷却水路

 图 1 转子线圈冷却水路示意图 Fig. 1 Schematic of cooling water path in rotor winding
2 一维近似计算方法 2.1 稳态温升计算

2.2 瞬态温升

 图 2 转子线圈单根水路强励计算分析模型 Fig. 2 Analysis model of forced excitation for single water path in rotor winding

 $\begin{split}&\left( {{C_{\rm w}} {} {G_{\rm w}} {} x + {C_{\rm {Cu}}} {} {G_{\rm {Cu}}} {} x} \right) {} {\rm d}\left( {\frac{{{\theta _x}}}{2}} \right) + {\rho _{\rm w}} {} Q {} {C_{\rm w}} {} {\theta _x} {} {\rm d}\tau = px {} {\rm d}\tau \end{split}\!\!\!\!\!\!\!\!\!\!$ (1)

 $\theta = \frac{{p l}}{{{\rho _{\rm w}} Q {C_{\rm w}}}}\left( {1 - {{\rm {e}}^{ - \frac{\tau }{M}}}} \right) + {\theta _0} {{\rm {e}}^{ - \frac{\tau }{M}}}$ (2)

 $M = \dfrac{{{C_{\rm w}} {G_{\rm w}} l + {C_{\rm {Cu}}} {G_{\rm {Cu}}} l}}{{2{\rho _{\rm w}} Q {C_{\rm w}}}}$

 $\theta = {\theta _{\rm m}} \left( {1 - {{\rm e}^{ - \frac{\tau }{M}}}} \right) + {\theta _0} {{\rm e}^{ - \frac{\tau }{M}}}$ (3)
3 数值模拟方法 3.1 控制方程

 $\nabla {\cdot} \; v = 0$ (4)

 ${\rho_{\rm w}}\nabla {\cdot} \left( { v \,{\cdot} \, v} \right) = \nabla {\cdot} { f_\tau } + {\rho_{\rm w}} g - \nabla P$ (5)

 $\frac{\partial }{{\partial \tau }}\left(\,{{\rho _{\rm w}}H} \right) + \nabla {\cdot} \left( \,{{\rho _{\rm w}} vH} \right) = \nabla {\cdot} \left( {\lambda \nabla t} \right) + {{ f}_\tau } {\cdot} \nabla v$ (6)

 $\frac{\partial }{{\partial \tau }}\left(\, {\rho H} \right) = \nabla {\cdot} \left( {\lambda \nabla t} \right) + S$ (7)

3.2 物理模型

 图 3 转子线圈三维物理模型 Fig. 3 Three-dimensional physical model of rotor winding
3.3 网格划分

 图 4 转子线圈横截面网格划分示意图 Fig. 4 Grid division for the cross section of rotor winding
3.4 边界条件和材料物性

3.5 计算步骤

4 计算结果与分析 4.1 调相机线圈强励瞬态温升的数值模拟结果

 图 5 调相机转子线圈2.5倍强励及冷却过程 Fig. 5 2.5 times excitation and cooling process of the condenser's rotor winding

 图 6 调相机不同时刻转子线圈内铜温及水温分布 Fig. 6 Temperature distribution of copper and water at different time in condenser's rotor winding

 图 7 调相机转子线圈不同倍数下强励、冷却过程出口铜温变化 Fig. 7 Copper temperature at the outlet of condenser's rotor winding at different excitation times and during cooling process

4.2 两种计算方法的对比

 图 8 两种方法获得的2.5倍强励20 s时沿流动方向的水温分布 Fig. 8 Water temperature distribution along the flow direction of 2.5 times strongly excited 20 s by two methods

5 结　论

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