论文总字数：24500字

摘 要

环氧乙烷（Ethylene Oxide，简称EO）是乙烯工业衍生物中的一种重要化工产品，广泛应用于洗染，医药，电子等领域。EO反应器是环氧乙烷/乙二醇（EO/EG）生产装置中的核心设备，我国长期依赖进口。扬子EO反应器的诞生，成功地打破了国外的技术垄断，对提高国内大型设备的设计、制造能力具有重要意义。

环氧乙烷生成过程中发出大量的热量，完全氧化副反应的反应热比主反应高十几倍。完全氧化副反应的发生，不仅使反应选择性大大降低，而且热效应大大升高，极易出现飞温。可见，EO化学反应的程度与反应气体含量、催化剂活性等有着很大的联系。EO反应器在实际运行过程中，可能出现局部放出大量热量的现象（如换热管靠近管程出口段），进而对EO反应器造成一定的影响甚至破坏。因而需要针对稳态运行时管程流体的温度变化展开研究。

本文结合扬子石化EO反应器的特点，应用CFD软件FLUENT展开数值模拟研究。主要研究工作和结论如下：

（1）利用流体分析前处理软件GAMBIT建立单根换热管模型，结合FLUENT软件分析实际稳态运行工况下，换热管内流体的温度场分布。结果发现：在预热区附近，管内流体温度迅速上升，在化学反应区，管内流体温度几乎维持在一个温度水平，至换热管下游，流体温度略有下降。

（2）研究了化学反应导致的换热管内流体局部过热工况下，换热管内流体的温度场。结果发现：该工况下，随着局部过热区域范围的增大，过热区域的换热管温度梯度也相应增大。

关键词：国产EO反应器，多孔介质，有限元，温度场

ABSTRACT

Ethylene oxide (referred to as EO) is an important chemical product of ethylene industrial derivatives, which is widely used in dyeing, medicine, electronics and other fields. EO reactor is the core equipment of ethylene oxide/ ethylene glycol (EO/EG) production plant, but this equipment always depends on importing in our country. However, Yangzi Company has successfully manufactured an EO reactor recently, which breaks the technology monopoly of foreign countries and have a very important meaning for improving the domestic ability of designing and manufacturing such large-scale equipments.

A lot of heat is generated in the process of ethylene oxide creation, and the heat of completely oxidized side reaction is about ten times higher than the main reaction. The occurrence of completely oxidized side reaction, not only reduces the selectivity, but also increases the thermal effect greatly, which leads to temperature runaway easily. Visibly, the extent of the EO reaction has a strong link with the amount of reaction gas and the catalyst activity, etc. In the process of actual operation, local phenomenon of heat release (such as the heat exchange tube close to the outlet of tube side) may emerge in the EO reactor, which in turn has a certain impact even damage on the EO reactor. Therefore, it is necessary to monitor the temperature changes in the tube side fluid during the steady-state operation.

In this paper, computational fluid dynamic (CFD) software FLUENT were used to numerically simulate the temperature filed of the tube side of EO reactor. The main research work and conclusions are as follows:

(1) Single tube model was established by GAMBIT and simulated by FLUENT. Fluid temperature profiles were obtained under steady-state condition. The results showed that fluid temperature rose rapidly in the vicinity of the preheating zone, while it maintained at a certain level in the reaction zone and then declined slightly in the downstream zone.

(2) Local overheating condition caused by reactions was studied. The results showed that local temperature gradient increased with the increasing area of the local overheating zone.

Keywords：Domestic EO reactor；Porous media; Finite element; Temperature field

目 录

摘 要 I

ABSTRACT II

第一章 绪论 1

1.1 课题背景 1

1.2 课题研究意义 2

1.3 换热器流场分析的发展 4

1.3.1 计算流体力学（CFD）技术的发展 4

1.3.2 多孔介质模型在换热器分析中的应用 5

1.4 FLUENT商用CFD软件包 8

1.4.1 软件介绍 8

1.4.2 FLUENT有限元分析过程 8

1.5 主要研究内容及方法 9

1.5.1 主要研究内容 9

1.5.2 研究方法 9

参考文献 9

第二章 模型建立及参数设置 13

2.1 引言 13

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