【作者】 许洋；

【导师】 张秋翔；

【作者基本信息】 北京化工大学 ， 化工过程机械， 2010， 硕士

【摘要】 采用低沸点液体介质冷却解决低转速、高扭矩电机冷却技术,是减少电机体积,提高电机效率较为有效的措施,尤其对我国大型电机石化行业,船用机械等可将庞大的减速箱去掉,极大地优化结构设计,降低设备成本。电机中冷却液的密封成为该技术的一个关键点。传统密封装置很难达到要求,针对这种工作环境我们提出采用新型密封技术,即磁脂密封。不同间隙和不同齿形的密封结构会影响磁场分布和密封耐压能力；而转轴和磁极的温度场对密封寿命有至关重要的影响。本文首先采用ANSYS分析软件,对磁脂密封不同结构的模型进行磁场的数值模拟,通过得出的实际密封简化耐压公式计算该密封的耐压能力,结果表明：磁脂密封能力好于普通磁流体密封,且由于磁脂密封的磁极与转轴间隙可以更大,所以适用于转轴径向跳动量大的场合,应用范围更广泛。研究表明,磁脂密封失效发生在什么位置是与密封间隙有关系的。双斜齿的密封耐压能力稍强,单斜齿次之,矩形齿稍弱；但三种不同齿形的耐压能力相差不大。由于矩形齿加工工艺简单,性能容易保证,因此在实际应用中一般选用矩形齿；极齿宽度太大或太小都会降低密封能力。对于本实验装置,极齿宽度取2-4mm较为合理；在一定范围内,不同的极齿高度对对密封压差影响不大。建立了实验装置的二维传热模型,并对该模型进行数值求解,获得转轴、磁极和永磁铁内部的温度分布,结果表明：受冷却水的影响,冷却水槽附近磁极温度明显低于转轴的温度；温度最低处发生在与氟利昂接触的内侧磁极,最低温度为80℃；由于转轴与磁铁之间为空气,导热系数低,因此永磁铁的温度较低。更多还原

【Abstract】 The liquid cooling technology of low boiling point that solved the low speed and high-torque motor cooling is an effective traditional craft of reducing the motor size and improving motor efficiency. The use of this technology can remove the large gear box, greatly optimize the structure design and reduce equipment costs for China’s large-scale electrical and petrochemical industries, marine machinery.Sealing motor cooling fluid is a key point of the technology. The generally traditional seal is difficult to meet the requirements. In view of this working environment, we propose using new sealing technology-the high viscous and non-Newtonian magnetic fluid sealing. Different sealing gap and different tooth structure will affect the magnetic field distribution and sealed pressure capabilities; while the temperature field of shaft and pole have a critical influence on sealing life.In this paper, high viscous and non-Newtonian magnetic fluid sealing different gap and different tooth structure was analyzed by using the finite element software package ANSYS. The sealing pressure was calculated by the equation of actual pressure resistance, the results show that the seal capacity of the high viscous and non-Newtonian magnetic fluid sealing is better than the ordinary magnetic fluid sealing and the high viscous and non-Newtonian magnetic fluid sealing is applicable to the occasions of large axial-radial pulse volume and has wide range of applications because of the large gap between of the magnetic pole and the shaft. The location of failure has relationship with the seal gap. The seal pressure capability of double-oblique tooth is slightly stronger than single-oblique tooth, and the seal pressure capability of rectangular tooth is weakest, but the seal pressure capability of three different teeth is or less. As machining process simply and easy to guarantee performance of the rectangular tooth, the rectangular tooth is generally used in practical applications. Too large or too small pole tooth width will reduce the sealing ability. For this experiment, more reasonable tooth width is 2-4mm; In a certain range, tooth height has very little effect on sealing pressure.The two-dimensional heat transfer model of experimental device is established and solved to obtain the temperature field of the shaft, pole and permanent magnet. The numerical results show that the temperature of the magnetic pole close to the cooling water trough is lower than the temperature of the shaft due to the cooling effect of water; the temperature of the inner pole near the Freon is lowest, the minimum temperature is 80℃; the temperature of the permanent magnet is relative lower because of the low thermal conductivity of the air between the rotor and the permanent magnet.更多还原