【作者】 李德胜；

【导师】 赵良举；

【作者基本信息】 重庆大学 ， 动力工程及工程热物理， 2008， 硕士

【摘要】 增压换热器是一种能提高流体压力而不直接消耗机械能的设备,因其结构简单可靠、运转费用低廉而在很多领域得到广泛应用。增压换热器虽然结构简单,但其设备内部流体的超音速混合过程非常复杂,存在着激波、边界层、剪切层的交互作用,混合机理尚不清楚。本课题从两相流音速计算和激波产生机理入手,设计了增压换热器,结合具体实验对增压换热器的特性进行深入研究,为工作参数及结构参数的优化设计提供理论依据。本文的主要研究结果如下:①在分析增压换热器内两相流动规律基础上,给出了喷射器的特性方程,设计了增压换热器的蒸汽喷嘴和混合腔的结构尺寸。②实验所得的增压换热器的出口热水压力均不同程度高于入口工作蒸汽压力,最高时可达1.5倍左右,很好的证明了该喷射器的增压效果,和理论分析吻合较好。③提高工作流体压力有助于提高喷射器的喷射系数及升压性能。④被引射流体压力越高,越容易被抽吸,喷射系数越高。⑤喷嘴出口面积和混合腔喉部结构对喷射器的喷射系数影响较大。更多还原

【Abstract】 Ejector with pressure gain has been used in a variety of applications due to their simplicity, reliability and versatility. Though the structure of ejector with pressure gain is very simple, the supersonic flow in the equipment is very complex because of the interaction of shock wave, boundary layer, and shear layer. The mix mechanism is not very clear. In this paper, begin with the calculation of the sound velocity and the analysis of the emergence of shock wave, we prepared an experiment for the further study of the characteristics of the ejector, supply the frame of reference for the design of geometrical factors and work factors. Main contributions of the paper are as follows:①Based on the law of two-phase flow in the ejector with pressure gain, according to its characteristic equation, full dimensions were designed, and the dimension of each part was given in detail.②According to the experiment, the pressure of exit hot water was more or less higher than the entrance working steam the maximum is up to 1.5 times. The effect of pressure gain was well proved. This was in good agreement with the theoretical analysis.③Increasing the pressure of working fluid is helpful for the eject coefficient and lift-pressure capability.④The higher the pressure of inject fluid, the easier it was sucked and the bigger the eject coefficient was.⑤The exit area of the nozzle and the throat structure of mixing chamber have great impact on eject coefficient.更多还原