【作者】 周英贵；

【导师】 袁竹林；

【作者基本信息】 东南大学 ， 制冷及低温工程， 2005， 硕士

【摘要】 本文采用数值模拟方法,对一种新型制取流体冰的方法进行了模拟研究,对其中一些关键问题进行了探讨,取得了相应的研究结果和结论。该新型制取流体冰方法的机理是通过一个特殊设计的雾化装置,把低温油介质均匀的导入一个直立的制冰通道,而把水雾化成细小水滴喷入制冰通道中的油介质环境中,水滴在油介质中被冷却直至结成冰颗粒,水滴在介质油中产生相变,所以在这个过程中水和油的流动是水滴,冰颗粒和油介质的多相流动。本文根据工艺的特性和要求,查阅相关文献和资料,找出了较为合适的两种油类介质:变压器油和缝纫机油,并做与水的相溶性对比试验。根据新型的制取流体冰方式,本文采用欧拉-拉格朗日数值模拟的方法对对油水多相流动混和物中的连续介质油和离散相水滴分别建立适时动态分布参数模型和离散颗粒轨道模型,对单个颗粒采用空间离散和时间离散的方法对水滴颗粒的内部导热和水滴表面与外界油介质对流换热进行数值模拟计算,得到了粒径,相对速度,通道管径等因素对水滴结冰时间的影响规律,同时运用颗粒轨道模型跟踪到具体的颗粒,模拟计算了喷入制冰通道中的水滴之间的碰撞特性和规律,通道进出口处的水滴的粒径分布状况,并相应的得到了介质油的速度场,温度场和水滴在油介质中的速度场,温度场。更多还原

【Abstract】 This papaer studies a new fluid ice technology. Numerical simulation method is used for some key questions of the new fluid ice technology. Relevant results and conclusions are obtained.The method of the new fluid ice technology is that low temperature oil-media is guided into a erect channel, and water is atomized in the low temperature oil by a atomization machine, water droplets are congealed. The mixture is three phases fluid of water droplets, oil and ice particles.This papaer refers a lot of literature and data about oil media, and finds two kinds of oil media which are fit for the technics characteristics: transformer oil and sartorius oil. The separability of water and oil media is tested.According to the new fluid ice technology, a transient mathematical model is used for the oil fluid and particle trajectory model is used for the discrete water droplets. Discrete time and discrete space are used for simulating the water droplet’s heat conduction and convection. Droplet’s icing time is abtained in the conditions of different droplet diameter, relative velocity and channel diameter. Particle trajectory model is used for following the tracks of water droplets, the occurrence of collision times between droplets is investigated and the related results are obtained. The oil’s temperature distribution, velicty distribution, water droplets’temperature distribution and velocity distribution are obtained by numerical simulation.更多还原