摘要锅炉自吸式取样器是一种不需要动力，自动取灰的装置。其原理是，被吸喷嘴连接到锅炉尾部烟道，尾部烟道内的气体压强是负压，外界常压空气就会从此缝隙中流入混合室，空气与锅炉烟气混合，在扩散室中，压力经过速度转换一直升高直到终压，空气和烟气的混合的气体通过分离器分离，锅炉烟灰由此过程被分离出来。本文侧重于对喷射器内部流场的研究，忽略了烟气中烟灰和杂质对流场的影响，只进行流场的数值模拟。本文应用FLUENT软件拟合在不考虑热传递的情况下的在引射器出口质量流量趋于稳定下的内部流场的流体压力分布图以及速度分布图，可以发现，压力呈上下对称分布，且明显在喷管的喉部有着明显的负压区域。而速度分布也是按照上下的对称分布，并且看的出在喷管的喉部有着最大速度，并且还对比分析了不同压力工况下的压力以及速度分布云图。 33702
关键词   锅炉内喷管引射器  FLUENT  流场  数值模拟
毕业论文设计说明书外文摘要
Title    The numerical stimulation of internal flow field of ejector based on FLUENT 
Abstract
The boiler is a kind of self suction sampler without power, automatic ash collecting device. The principle is, the suction nozzle is connected to the boiler flue gas and the gas pressure in the flue at the tail of the negative pressure, the outside atmospheric pressure air will then slot into the mixing chamber, air and flue gas mixture, in the diffusion chamber, pressure after the speed conversion increased continuously until the final pressure, air and flue gas mixed gas through the separator, boiler soot from the process were isolated. The study of the flow field in the injector is focused on the effect of soot and impurities on the flow field, and the numerical simulation of the flow field is carried out. In this paper, the application of FLUENT software fitting without considering the heat transfer on the introduction of the injector outlet mass flow tends to stable under the internal flow field of fluid pressure distribution diagram and the velocity profile can be found, pressure is distributed symmetrically from top to bottom and significantly in the nozzle throat has a significantly negative pressure region. And velocity distribution is in accordance with the symmetrical distribution, and look at the maximum velocity in the nozzle throat, and also compared and analyzed under different pressure conditions of pressure and velocity contours.
Keywords   ejector   numerical stimulation   flow field   FLUENT
目   次
1 引言•1
1.1 课题背景 1
1.2 当下发展方向•2
1.3 FLUENT软件介绍3
1.4 课题研究的侧重点•4
2  理论基础 •5
2.1 能量守恒定律•5
2.2 质量守恒定律•5
2.3 动量定理•6
3 湍流分析•7
3.1 湍流模型•7
3.2 湍流的控制方程•8
4 模型设计11
4.1 模型的简化处理11
4.2 网格的划分12
4.3 具体建模数据12
4.4 边界条件14
4.5 计算过程及结果14
结论19
致谢20
1  引言
1.1 课题背景
    随着人们生活水平的日益提高，引射器在人们的日常生活中扮演的越来越重要的角色。引射器，通常又有一种说法叫做喷射器，一般来说流体通过引射器能够将自己的质量或者是能量传递出去，进行一些流体的分离分流或者是能量交换[1]。引射器的优点是它能比较稳定地工作，并且有较高的工作效率，它的结构简单易于建模分析，并且工作时不易受外界影响让其拥有持久工作能力，同样地，因为结构不会过于复杂，所以当收到损坏或者过旧时人们也很方便地对其进行文修改善等。 基于FLUENT的引射器内部流场数值模拟:http://www.youerw.com/wuli/lunwen_30943.html