【作者】 王晓东；

【导师】 许洪元；

【作者基本信息】 清华大学 ， 流体机械及工程， 2002， 硕士

【摘要】 旋转喷射泵是近些年才发展起来的一种极低比转数泵，主要用在碳黑、食品、化工以及深井采矿系统中用以提供小流量高水头的稳定出流。旋喷泵工作原理比较特殊，结构简单，性能曲线稳定，维护方便。我国从九十年代末开始引进，目前国内对旋喷泵的研究还比较少，尤其是对集流管以及转子腔内部的流动状况研究更是一个空白。集流管是旋喷泵的重要的过流部件，它的设计的好坏直接影响到旋喷泵的效率。本文综合了国内对旋喷泵的研究，根据实际工况设计了多种模型并用数值模拟的方法对集流管及转子腔的内部流动进行了分析研究。论文的一部分是集流管的设计及内部流动研究。集流管的设计参照了目前国内对集流管的研究并提出了一种改进型的集流管模型。利用DELPHI6.0设计了一个旋喷泵集流管的参数化设计软件。对集流管的三维粘性紊流模拟计算是建立在雷诺平均的Navier-Stokes方程的基础上，紊流封闭模型采用目前工程上应用比较广泛的模型，在靠近固壁区采用了标准的壁面函数法。数值方法上，先将控制方程转换到贴体坐标系下，然后对其进行有限差分离散。速度压力的求解方法采用速度压力耦合算法即SIMPLEC算法。通过对集流管的数值模拟，得出了集流管内部流动的速度场、压力场和湍动能的分布，通过分析速度、压力和湍动能的分布比较了各种模型的优劣，得出如下结论：对集流管的改型可以达到与原来集流管相同的水力性能；集流管的第一转弯处容易产生气蚀；集流管的扩散角一般在5度以内；集流管进口形状对其内部压力分布有较大影响。论文的另一部分是对转子腔内部流动的数值模拟。由于转子腔是与叶轮一起高速旋转，其内部流动无法用试验的方法测出。集流管在转子腔中是静止的，其对转子腔内流动的影响直接关系到旋喷泵的水力性能。通过数值模拟，得到了转子腔内部流动的速度场、压力场和湍动能分布。得出如下结论：转子腔内部速度沿半径呈线性变化；转子腔在轴向上速度变化不大；转子腔内部的压力场是一致的；集流管进口处压力、速度、和湍动能变化比较大，应重点设计；集流管扩散段翼型对流动影响不大。更多还原

【Abstract】 The Roto-Jet pump is a new kind of very low specific speed pump which is developed in recent years. It is always used in carbin black, food production, chemical industry and deep well mining system to supply the steady outflow with low flux and high pressure. The work theory of the Roto-Jet pump is very specific and it has very simple construction and smooth performance curve and cheap maintain. Our country began to introduce this pumps in 1990s. The research on it is very poor now especially on the flow in the pick-up tube and rotating case. The pick-up tube is one of the most important overflowing parts, and its design result will directly influent the efficiency of the Roto-Jet pump. All the research on this pump is analysis by synthesis in this paper and many models are designed according to the real condition. The flow in the pick-up tube and rotating case is researched by numerical simulation. One part of this paper is the researching of the design and flow of the pick-up tube. The design of the pick-up tube accords to the research on the roto-jet pump by other people in China and a new type model is designed. A parameterize designing software is made by Delphi 6.0. Numerical simulation on the three-dimensional turbulence flow in the pick-up tube is based on Reynolds time-average Navier-Stokes equations. The k-εTurbulence-closed model is used in this paper. In the near wall area the standard wall function is used. The finite difference discrete is applied on controlling equations after they are converting into the body fitted coordinate system. SIMPLEC algorithm is used to solve the velocity and pressure field. So that the distribution of the velocity, pressure and kinetic energy in the pick-up tube is shown to us by numerical simulation. We can compare the models through analysising the velocity and pressure. We get that: the new type model has same performance as the old one. Cavitation is liable to appear in the first elbow. The angle of flare is always less than 5o. The shape of the pick-up’s inlet influence the internal pressure much.Another part of this paper is numerical simulation of the flow in the rotating case. Because the rotating case rotates with impellers with high speed, the flow in it can’t be measured by means of experiments. The stationary<WP=6>pick-up tube will influence the flow in the rotating case. So that the distribution of the velocity, pressure and kinetic energy in the rotating case is shown to us by numerical simulation. We get that: Velocity in the rotating case linearly changes along the radius and velocity changes little on the axis direction. Pressure in the rotating case has the same value. Velocity, pressure and kinetic energy change a lot around the inlet of the pick-up tube, so it should be importance design. Aerofoil around the diffuse segment of the pick-up tube influences the flow in the rotating case little.更多还原