题名 | 大型水轮发电机蒸发内冷系统的基础理论研究及自循环系统的仿真计算; 大型水轮发电机蒸发内冷系统的基础理论研究及自循环系统的仿真计算 |
作者 | 1阮琳,电工研究所 |
学位类别 | 博士 |
答辩日期 | 2004 |
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 | 蒸发冷却技术 水轮发电机 两相流 仿真计算 模型实验 evaporative cooling technology hydro-generator two-phase flow simulation model experiment |
其他题名 | 大型水轮发电机蒸发内冷系统的基础理论研究及自循环系统的仿真计算 |
学位专业 | 电机与电器 |
中文摘要 | 蒸发冷却技术中所涉及的两相流动和传热问题相当复杂,至今没有十分通用计算方法,导致蒸发冷却循环系统的设计计算还有待进一步完善。针对这种情况本论文为水轮发电机定子绕组自循环蒸发冷却系统提出了一套通用有效的理论计算方法,更为准确地计算了蒸发点的位置;计算了起沸点和净蒸气产生点:为两相段摩擦阻力放大倍数的计算选择了Friedel方法,并根据实验结果对其进行了合理地修正'在两相流体与空心导线壁面换热计算中,采用了划分流型分段取独热系数的方法,使空心导线壁面温度分布的计算更为准确。本文在理论计算算法基础上用Visual C++开发了具有GUI的专业应用软件,该软件功能完善,使用简便。为了验证仿真计算的准确性,进行了冷却系统的模型实验并与仿真结果对比。比较结果显示二者之间的最大相对误差绝对值不超过10%。这充分验证了仿真计算软件的数学模型是准确的,计算结果具有可靠性。与此同时,为了对两相流问题有更深层次的认识,本文进行了一系列空心导线内流体流动和传热特性比较的原理性实验,并根据实验结果推导出了矩形空心导线两相段总压降放大倍数的实验关联式,简化了工程计算,提高了仿真精度。 The relating problems of two-phase flow and heat-transfer in the evaporative cooling loop are very complicated with no common design and calculation methods in use up to the present and no criterion has developed from the technologic point of view, which, results in the design calculation of the evaporative cooling system should to be perfected. Aiming at this situation, this paper provides a general and effective theoretical calculative method for the operational states of the stator windings' close-loop-self-circulating - CLSC evaporative cooling system of hydro-generators. Among the theoretical calculative methods, the evaporative point was more accurately computed; ONB and FDB were calculated; the Friedel method was selected to compute the two-phase frictional resistance and it was reasonably corrected on the basis of the experimental results; for the heat exchange between two-phase fluid and conductor's wall, a kind of partition of flow patterns was adopted and the corresponding convective heat exchange coefficients were calculated according to the different flow patterns, which make the computing result of the temperature distribution more accurate than ever. On the basis of the theoretical algorithm, a kind of professional applied software with GUI was developed. This software has complete functions and can be used easily. At the same time, the experiment was done in a cooling system model in order to verify the validity of the simulation. Comparative results show that the maximum relative errors between them are less than 10 percent. This result fully validates the mathematical model of the circulating cooling system is justified and the algorithm of the numerical simulation is correct. Besides, in order to have further knowledge about the characteristics of the two-phase flow, the theoretic model experiment of the two-phase flow and heat transfer was done in vertical hollow conductors with different inner sizes. According to the experimental results, for the amplification ratio of the general two-phase pressure drop to the liquid flowing resistance in rectangular hollow conductors, the experimental correlation was developed, which simplifies the engineering calculation, reduces the error sources and improves the simulating precision. |
语种 | 中文 |
公开日期 | 2010-10-18 |
页码 | 134 |
内容类型 | 学位论文 |
源URL | [http://ir.iee.ac.cn/handle/311042/6860] ![]() |
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阮琳,电工研究所. 大型水轮发电机蒸发内冷系统的基础理论研究及自循环系统的仿真计算, 大型水轮发电机蒸发内冷系统的基础理论研究及自循环系统的仿真计算[D]. 中国科学院电工研究所. 2004. |
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