【作者】 祁晓锋；

【导师】 冯青； 夏继胜；

【作者基本信息】 景德镇陶瓷学院 ， 热能与动力工程， 2009， 硕士

【摘要】 高温旋风分离器是循环流化床锅炉分离机构的重要组成部分,由于其结构简单,分离效率高,广泛运用于循环流化床锅炉中。为了掌握高温旋风分离器内部流场特性,本文以计算流体力学软件Fluent6.3为基础,景德镇电厂150WM循环流化床锅炉高温旋风分离器为研究对象,对其内部流场进行模拟和分析。通过本文的研究,首先确定一套适合高温旋风分离器内部流场计算的数值方法,在这基础上,对高温旋风分离器气相流场进行了模拟研究,其中包括速度场、压力场以及湍流结构的分析。其次对高温旋风分离器两相流场进行了研究,包括气固两相流模型,颗粒运动轨迹、颗粒浓度场的分布、分离效率的研究等内容。最后提出了一种新型弧形入口型的高温旋风分离器。(1)在对旋风分离器内部流场进行数值模拟时,湍流模型采用雷诺应力模型、对流项采用QUICK格式进行离散、对于控制方程组采用SIMPLEC算法求解、采用分区组合来划分网格。(2)从模拟中可以清楚看出,总体上高温旋风分离器内部流场由两层涡流组成。在入口区,可以看到气流紊乱,对壁面造成严重的冲刷。在旋风筒区域流场的对称性较好,而在锥体部分,流场的对称性较差。(3)本文提出一种弧形入口型高温旋风分离器,并对其流场进行模拟。这种结构使得入口流场较为稳定,减少了对壁面的冲刷,内部流场的对称性要好于原型,同时分离效率有了一定的提高。更多还原

【Abstract】 High temperature cyclone separator with simple structure and high separation efficiency is an important part of CFBB with separation equipment ,which has been widely used in CFBB. By using the computational fluid dynamics software FLUENT6.3, the internal flow in high temperature cyclone separator of Jingdezhen Power 150MW CFBB is simulated and analyzed to understand the flow characteristics in separator.Through researching this thesis, the method of numerical for computing the internal flow in high temperature cyclone separator will been confirmed at first, the gas flow in cyclone separator is simulated afterwards, including velocity field, pressure field and analysis of turbulence structure, two-phase flow is researched, which includes gas-solid two-phase flow model, paths of particles , particles concentration field distributions and so on. A new high temperature cyclone separator with arc way is presented in the end.(1) The internal flow in cyclone separator is simulated by RSM model for turbulent flow, QUICK format for different scheme, SIMPLEC for controlling equations, zoning combination of grid.(2) The internal flow in high temperature cyclone separator is double vortex on the whole flow from simulating. In the entrance area, the gas flow is disordered and wall is strong erosion and the flow is symmetrical in cyclone tube area, however, the flow is dissymmetrical in cone area.(3) The flow is simulated for arc way high temperature cyclone separator , the flow in entrance area is stability and erosion of wall is mitigated, symmetrical in internal flow is better than original model, and separation efficiency is enhanced.更多还原