论文总字数：27451字

摘 要

了解固液两相流在泵内的流动情况以及对泵外特性的影响有十分重要的现实意义，在工程上，更多情况要面对的是混杂固体颗粒的两相流流体。固液两相流的特点在于固体颗粒会提高泵的传输负荷，并且在泵内流动运输时会对泵内部造成不可避免的磨损，本文希望通过研究两相流的内部流动情况，进而找到应对磨损可能性，并且对外特性进行预测，提高工程效率，降低成本。本文采用数值模拟的方法，研究颗粒属性（粒径、体积分数和密度）对泵内的定常流动的影响，研究结果可为输送两相介质泵的优化设计提供参考。本文的主要研究内容和结论如下：

1. 对泵输送固相为单分散颗粒群的固液两相流动进行了定常数值计算，研究了不同的颗粒属性（粒径、体积分数和密度）对泵内部流动的影响。结果表明，影响内部流动规律的主要因素是粒径和体积分数。
2. 研究了泵内部两相流流动的主要规律。其结果为，部分固体颗粒随流体由前盖板冲刷后盖板并集中于此，当颗粒属性数值较高时易对叶轮工作面以及蜗壳近出口位置形成冲击和堆积，大大影响了泵的使用。

3）研究了颗粒属性对泵外特性的影响。结果表明随着三种颗粒属性数值的提升，体积分数是当中影响最大的因素，并且可以推测，泵的运行存在最佳工况。

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关键词：固液两相 颗粒属性 外特性 内部流动 数值模拟

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Study on the characteristics of Solid-liquid Two-phase Flow in centrifugal pump

ABSTRACT

It is very important to understand the flow characteristics of the solid liquid two phase flow in the pump and its influence on the external characteristics of the pump. Solid-liquid two-phase flow characteristics is solid particles can improve the transmission load of the pump, the pump internal inevitably and in the pump flow transport of wear and tear, we hope that through the study of two-phase flow of internal flow, and then find the respond to wear the possibility, and external characteristic of prediction, improve work efficiency and reduce the cost. In this paper, the numerical simulation method is used to study the influence of particle size, volume fraction and density on the steady flow of the pump. The results can provide reference for the optimal design of the two phase medium pump. The main research contents and conclusions of this paper are as follows:

1) A solid-liquid two-phase flow, its solid phase consisting of monodisperse particles, made a steady numerical calculation and the effect of different particle sizes (particle size, volume fraction and density) on the internal flow of the pump is studied. The results show that the main factors affecting the internal flow law are particle size and volume fraction.

2. The main laws of two-phase flow in the pump are studied. As a result, part of the solid particles with the fluid scour the impeller back shroud from the front shroud of impeller and focus on the, when the properties of particles numerically higher easy of impeller and volute near the exit position impact on the formation and accumulation, greatly affected the use of the pump.

3) The effect of particle properties on the pump characteristics is studied. The results show that the volume fraction is the most influential factor with the increase of the three kinds of particle properties, and it can be inferred that there is the best operation condition of the pump.

Key words: solid-liquid two phase; particle properties; external characteristic; internal flow; numerical simulation;

目 录

摘 要 I

ABSTRACT II

目录 i

第一章 绪论 1

1.1 固液两相流的研究意义 1

1.2 固液两相流的研究方法 1

1.2.1 理论研究 1

1.2.2 实验研究 1

1.2.3 数值模拟 2

1.3 研究内容 5

1.4 研究方法 5

第二章 离心泵实体建模及数值计算 7

2.1 CFD相关理论介绍 7

2.2 固液离心泵的Pro/E三维实体建模 8

2.2.1 吸入室造型 9

2.2.2 叶轮造型 9

2.2.3 压出室造型 9

2.3 网格划分 10

2.4 边界条件 12

2.5 控制方程 13

2.5.1 连续性方程 13

2.5.2 N-S方程 13

2.5.3 能量守恒方程 14

第三章 离心泵内部流动分析 15

3.1 离心泵内两相流流动规律一般结论 15

3.2 颗粒体积浓度对流场的影响 18

3.3 颗粒直径对流场的影响 19

3.4 固相密度对流场影响 20

第四章 泵外特性预测 22

4.1 外特性预测主要手段 22

4.2 具体算法 23

4.2.1 扬程 23

4.2.2 轴功率 23

4.2.3 效率 24

4.3 粒径对外特性的影响 24

4.4 体积分数对外特性的影响 26

4.5 密度对外特性的影响 29

4.6 本章小结 31

第五章 结论与展望 32

5.1 结论 32

5.2 展望 33

参考文献 34

致 谢 36

第一章 绪论

1.1 固液两相流的研究意义

20世纪70年代末期左右，我国固液两相流泵的研究才刚起步，依照两相流理论进行设计和研发的泵直到80年代中页才开始被重视以及使用。通过数十年间的不断发展，我国的两相流技术理论的到了升华，我国的诸多学者将两相流理论付诸应用，对固液两相流泵开展了水力设计和试验研究，其中产生了很多有重大意义的经验和教训^[1][2]。

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