论文总字数：28121字

摘 要

压缩空气储能系统是一种能够实现大容量和长时间电能储存的电力储能系统，可以有效解决各种能源应用问题。随着其应用不断扩大，对其系统设备的研究也越发深入。其中，蓄热器的储热在整个压缩空气储能系统中尤为重要。因此针对蓄热器内部管道储气的研究是提高储热效率的重点，也是提高储气的安全性、经济性和大量性的关键问题，由于希望热损失尽可能小，蓄热器内常采用缠绕式管子。目前所研究的问题是基于实验分析与数值模拟两种，实验分析方法研究的问题是基于相似原理的指导，通过对实际问题进行实验模拟的方式来确定的，在工程研究中具有广泛的应用，但相比而言，耗时较长，成本相对较高。

本文即尝试利用有限元模拟技术对蓄热器管程进行模拟和分析，考察管内压缩空气动态流动的速度、温度和压强的变化。主要研究内容及结论如下：

1. 基于同一规格的蓄热器缠绕式管子模型，对管内储气过程进行研究，数值模拟分析管内压缩空气压强、温度、速度的分布情况。结果表明：管内流体温度、压强分布均匀，从管口到封闭端，压强逐渐下降，而温度逐渐上升；速度矢量分布从开始的杂乱无章到最后的整齐统一，变化明显；而在缠绕管横截面上，速度大小由圆心到管壁逐渐降低，管壁速度大小为0。
2. 对压缩空气在缠绕管内压强和温度随时间的变化进行研究，讨论了入口质量流量对管内流体温度和压强以及进出口压降的影响。结果表明：质量流量对温度和压强的变化有很大的影响，入口的质量流量越大，压强和温度随时间的变化也就越大，压强呈线性增长，而温度随时间增长时，增长率逐渐降低；质量流量的增大，使得管子进出口的压降也随之增大。
3. 基于不同工况的缠绕管子模型，模拟并讨论了不同管口径和缠绕直径对管内流体温度和压强的影响。结果表明：管口径越大的管子，管内压强和温度随时间增长的越慢，相反，管口径越小的管子，管内压强和温度随时间增长的越快，同一时间内达到的值越大；缠绕管的缠绕直径越小的管子，管内压强和温度随时间变化的越快，相反，缠绕直径越大的缠绕管，管内压强和温度随时间增长的越慢，同一时间内达到的值越小。这为管子规格尺寸的选择提供了帮助，从而实现选材的合理性与优化性。

关键词：压缩空气储能 缠绕管式蓄热器 温度 压强 速度 有限元模拟

ABSTRACT

Compressed Air Energy Storage system is able to achieve a large-capacity power storage system and prolonged the energy storage, it can be effectively applied to solve various problems. With the continuous expansion of its application, system equipment also studied more in depth. Wherein the heat storge of accumulator is particularly important in the Compressed Air Energy Storage system. Therefore, for the study of the gas storage of the internal accumulator pipeline is focused on improving the efficiency of thermal storage and improving security, economy and great number of the gas storage. In order to control the heat loss as small as possible, accumulator often used winding tube. Now the study is based mainly on the experimental analysis and numerical simulation. Experimental analysis of the study is based on similar guiding principles, practical issues of experimental simulation approach to identify, and in engineering research in a wide range of applications, but in comparison, the time is longer, the cost is relatively high.

This paper attempts to use finite element simulation techniques to simulate and analyse the accumulator tube and study the changes of velocity, temperature and pressure. The main contents and conclusions are as follows:

1. Based on the same size regenerator winding tube model of the process gas tube to study the distribution of the pressure, temperature and velocity of the compressed air by the numerical simulation. The results shows that: the temperature and the pressure of the fluid in the tube are uniform distribution. From the mouth to the closed end of the tube, the pressure is gradually decreased, while the temperature was gradually increased;velocity vector changed significantly that its distribution disorganized from the beginning to the end of uniform; in the Pipe cross-section, the speed is gradually reduced from the center to the wall and the wall velocity size is 0.
2. Study changes of pressure and temperature over time of the compressed air in pipe, discuss the influence of the tube inlet mass flow rate of fluid temperature and pressure as well as import and export drop. The results shows that: the mass flow rate influenced a lot change in temperature and pressure, the greater the mass flow of the inlet, the greater changes of pressure and temperature over time, pressure increased linearly with time while the growth rate of temperature gradually reduced; mass flow rate increases, so that the voltage drop across the tube and export increases.

(3) Based on different conditions of Pipe sub-models, simulate and discuss the effects of different pipe diameter and the diameter of the tube on temperature and pressure of fluid. The results shows that: the larger diameter pipe tube, the slower growing of pipe pressure and temperature over time, on the contrary, the smaller the pipe diameter of the tube, the faster growing of the pressure and temperature, the greater the value reached in the same time; the smaller pipe winding diameter, the faster tube change of pressure and temperature over time, on the contrary, the larger the winding diameter of the winding tube, the slower growth of pressure and temperature over time,the smaller the value reached in the same time.This provides a helpful option for pipe size specifications, enabling the selection of optimization and rationality.

Keywords: Compressed Air Energy Storage; winding tube accumulator; temperature; pressure; velocity; finite element simulation

目 录

摘 要 I

ABSTRACT III

目 录 V

第一章 绪论 1

1.1 压缩空气储能系统简介 1

1.1.1 课题背景 1

1.1.2 压缩空气储能系统的技术特点 2

1.1.3 压缩空气储能系统应用现状 3

1.1.4 压缩空气储能系统的分类 4

1.1.5 压缩空气储能系统的热力过程分析 5

1.1.6 压缩空气储能技术的发展趋势 6

1.2 储热系统性能分析 6

1.3 缠绕管式热交换器的特征和用途 7

1.4 缠绕管式热交换器的构造和使用 8

1.5 缠绕管简介 9

1.6 管内压缩空气动态流动的研究意义 10

1.7 本文所做工作 10

第二章 物理模型建立 11

2.1 简化假设 11

2.2 圆形截面缠绕管简化模型 11

2.3 圆形截面管建模过程 11

2.4 网格划分 12

2.5 定义边界条件 13

第三章 固定尺寸下管内的数值模拟分析 14

3.1 利用FLUENT-3D求解器对圆形截面缠绕管进行求解 14

3.2 圆形截面缠绕管数值模拟分析 17

3.2.1 速度分布 17

3.2.2 压力分布 19

3.2.3 温度分布 19

3.2.4 不同质量流量对压强的影响 20

3.2.5 不同质量流量对温度的影响 22

3.2.6 入口速度与压降的关系 24

3.3 小结 25

第四章 不同工况下管内温度、压强的分析 26

4.1 不同管口径对管内温度、压强的影响 26

4.1.1 管口径对管内温度的影响 26

4.1.2 管口径对管内压强的影响 26

4.2 不同缠绕管缠绕直径对管内温度、压强的影响 27

4.2.1 缠绕管缠绕直径对管内温度的影响 27

4.2.2 缠绕管缠绕直径对管内压强的影响 28

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