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题名	转子管道式自循环蒸发冷却系统的实验研究和仿真计算; 转子管道式自循环蒸发冷却系统的实验研究和仿真计算
作者	1王增强,电工研究所
学位类别	博士
答辩日期	2008-05-26
授予单位	中国科学院电工研究所
导师	1顾国彪,电工研究所
关键词	转子冷却系统 蒸发冷却技术 旋转冷凝器 热电式流量计 仿真计算 cooling system of the rotor evaporative cooling technology rotational condenser thermo-electric flowmeter simulative computation
其他题名	转子管道式自循环蒸发冷却系统的实验研究和仿真计算
中文摘要	鉴于空冷、氢冷、水内冷、热管冷却在转子冷却方面的不足，迫切需要研发一种新型的转子冷却系统。而蒸发冷却技术具有安全、可靠、冷却效果好、维护简单等优点，并且在水轮发电机定子冷却方面具有比较成熟的经验。因此我们借鉴以往蒸发冷却技术的成熟经验以及热管技术在电机转子冷却方面的特点，开创性地设计了一种转子管道式自循环蒸发冷却系统模型。 本论文的研究目的在于设计了一种转子管道式自循环蒸发冷却系统实验装置 ，通过该实验装置解决转子管道式冷却系统的旋转冷凝器、二次冷却水循环系统、蒸发管、回液管、转子左右端盖和转子本体之间的连接、焊接、安装、密封以及在检漏过程中出现的难题。为了测量该实验系统中的温度、压力和流量以及观测液位和循环状态，我们找到了准确测量这些参数的方法和手段，特别是攻克了转子流量测量的困难，开发出了一种专门用于测量转子冷却系统流量的热电式流量计，并校正了该流量计的电阻差和流量的关系曲线。这种流量计测量精度高，误差较小。 本论文在实验的基础上，对该冷却系统的流动和传热的理论进行了分析，分 析了蒸发管内起沸点、净蒸汽产生点、蒸发点、最大热负荷、加速度压降和摩擦压降以及各段的换热系数的计算方法。通过两相流动变量参数之间的内在的牵连关系，把定子自循环系统的两相流动与传热计算方法移植应用到转子上，并综合考虑转子旋转产生的离心力的影响，得到了转子管道式自循环蒸发冷却系统的计算程序。对比实验结果和计算结果，发现计算结果接近实验结果，计算程序准确、可靠。同时运用计算程序对不同液位、转速和热负荷下冷却效果进行了预测，发现：在热负荷和液位一定时，随着转速的增加，沿蒸发管的最大温升不断增大，在蒸发点附近温度达到最大值；在转速和液位一定时，随着热负荷的增大，蒸发管出口的干度逐渐增大，蒸发管的最大温升也逐渐增大，但温升幅度减小；在转速和热负荷一定时，随着液位的增加，蒸发管的最大温升有增大趋势，但增幅逐渐减小；当达到一定转速后（大于800转/分），较小的液位高度就能使冷却介质成单相流动。通过大量计算结果发现转子管道式冷却系统的冷却效果不错，有着广阔的应用前景。 为了在几何尺寸、热负荷和转速相同的情况下，比较转子管道式蒸发冷却系统与转子开槽式冷却系统的冷却效果。本论文通过仿真软件CFX计算了转子开槽式冷却系统的三维温度场，计算后发现转子开槽式冷却系统的转子最大温升比转子管道式自循环冷却系统的温升要高7℃左右，由此可见转子管道式自循环冷却系统的换热效果是比较不错的。 In view of the disadvantage of air cooling, hydrogen cooling, water inner-cooling and heat pipe cooling technology used for the rotor, it is urgently needed to develop a new kind of rotor cooling system (RCS). Moreover, evaporative cooling technology (ECT) has the advantage of security, reliability, better cooling effect and convenient maintenance, and aslo has the comparatively matured experience for the stator cooling of hydro-generator. So we refer to the matured experience of the ECT and the heat pipe cooling technology used for the rotor, and have innovatively designed a model of pipeline-type rotor self-circulating evaporative cooling system (ECS). The dissertation aims to design an experimental unit for the self-circulating ECS of the pipeline-type rotor, by which, we resolve the problems of connection, welding, installation, seal between the rotating condenser, circulating system of the re-cooling water, evaporating pipe, returned liquid pipe, right and left end cap of the rotor and rotor body and in the course of checking leakage. For measurement of the temperature, pressure and flow rate of the experiment system and observation of the liquid level and circulation status, the methods and ways of exactly measuring these parameters have been found, especially, the problem of measuring the rotor’s flow rate is resolved, and a thermo-electric flowmeter for technically measuring the flow rate of the RCS has been developed, at the same time the relationship curve of resistance difference and flow rate is calibrated. The flow rate is with high measuring accuracy and less error. Based on the experiment, the flow and heat transfer of the cooling system is analyzed in the dissertation, and the onset of bubble, pure vapor arising-point, evaporative point, maximum heat load, pressure drop of acceleration and friction and the coefficient of heat exchange thereof in the evaporating pipe have been analyzed. By the intrinsic interrelationship between the parameters of two-phase flow variables, and the influence of centrifugal force being wholly taken into account, the computational method of two-phase flow of stator self-circulation system is used for the pipeline-type rotor self-circulating ECS. After comparing the computational value with the experimental value, we find that the error is little which shows that the computational program is accurate and reliable. At the same time, the computational program is also used to forecast the cooling effect on condition of different liquid level, rotation speed and heat load. Then we find that the maximum temperature rise along the evaporative pipe is gradually increased and at the evaporative point it reaches to the maximum value with the rise of rotation speed when the heat load and liquid level are both constant, the dryness of evaporative pipe outlet is gradually increased and maximum temperature of the evaporative pipe is also gradually increased but its increment is decreased with the increase of heat load when the rotation speed and liquid level are both constant, the maximum temperature rise of evaporative pipe trends to increase but the increment is gradually decreased when the rotation speed and heat load are both constant, the cooling medium will flow in single phase status even if with a lower liquid level when the rotation speed reaches a value such as greater than eight hundred of revolution per minute. Many computational values show that the cooling system has a good cooling effect and with the bright application future. For comparing the cooling effect of the present cooling system with the cooling system of groove-type rotor with the same size, heat load and rotation speed, the three-dimensional temperature field of the cooling system of groove-type rotor has been simulated by the CFX simulation software. After computation, the maximum temperature rise of the present cooling system is lower about seven centigrade degree than the cooling system of groove-type rotor, therefore the present cooling system has a good effect on heat exchange.
语种	中文
公开日期	2010-10-18
页码	150
分类号	TM3;TM5
内容类型	学位论文
源URL	[http://ir.iee.ac.cn/handle/311042/6662]
专题	电工研究所_其他部门_其他部门_博士学位论文
推荐引用方式 GB/T 7714	1王增强,电工研究所. 转子管道式自循环蒸发冷却系统的实验研究和仿真计算, 转子管道式自循环蒸发冷却系统的实验研究和仿真计算[D]. 中国科学院电工研究所. 2008.

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