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ANSYS冰丸穿越高温炉膛的传热过程模拟

时间:2020-12-19 19:16来源:毕业论文
研究冰丸发射后在炉膛中飞行时的换热过程,首先建立冰丸在炉膛中飞行时的换热模型,然后利用数值模拟和 VB编程的手段,对换热过程进行模拟,最终给出数值模拟的结果以及冰丸内

摘要我国电站锅炉以燃煤为主。如果燃煤具有较高的灰分和硫分、较低的灰熔点、炉内局部出现还原性气氛、负荷偏高、空气动力场失调等情况,容易诱发锅炉炉膛的结渣,严重时还会导致受热面的高温腐蚀。炉膛结渣还会影响受热面的传热效率,导致锅炉的热效率下降。在运行中对炉膛进行除灰(除渣)操作,是锅炉运行的一个关键问题。现有的吹灰器主要利用动能除灰的方式,对锅炉的安全高效运行有不利影响,而冰丸除灰技术主要利用冰丸溶解时吸收热量在渣层内产生热应力破坏渣层结构从而达到除灰的目的,对锅炉本体的动能冲击小。 本文主要研究冰丸发射后在炉膛中飞行时的换热过程,首先建立冰丸在炉膛中飞行时的换热模型,然后利用数值模拟和 VB编程的手段,对换热过程进行模拟,最终给出数值模拟的结果以及冰丸内部的热应力分布。61042  
毕业论文关键词  电站锅炉,炉膛,吹灰,冰丸,传热 
Title     Heat transfer process simulation  of  Ice pellets through high-temperature furnace 
Abstract In China the main fuel of power plants is coal which contains high ash content and  sulfur content 锄d has low ash fusion temperature.In the case that in the furnace the local atmosphere is reductive or the load is too high or the air dynamics is disordered , slagging  will be easily induced.Worsely, it will lead to high temperature erosion on the heating surfaces.Slagging in the furnace affects the heat transfer efficiency of the heating surfaces and causes the decreasing in the thermal efficiency of the boiler . In the operation process , ash . disposal(or slag.disposal)becomes a critical problem.The existing ash sootblowers    take the advantage of momentum,and have an adverse effect on the safety and efficiency of the boiler operation. The main advantage of ice pellets ash technical is ice pellets’ absorbing heat when dissolved. It has thermal stress to damage slag layer, so as to achieve the purpose of ash, and have small impact of kinetic energy on the boiler. This paper studies the heat transfer process of ice pellets after launching when flying in the furnace. First we need to establish the heat exchanger model when ice pellets flying in the furnace. Then we use numerical simulation and VB programming means to simulate the process of the heat exchanger. Finally results of numerical simulation are given as well as the thermal stress distribution inside the ice pellets.
Keyword    Power plants,furnace,ash-disposal,ice pellet,simulate 

1 绪论..  7 

1.1 炉膛结渣概述  ..  7 

1.1.1 炉膛结渣的分类  8 

1.1.2 炉膛结渣的危害  8 

1.1.3 炉膛结渣的防止  9 

1.2 炉膛吹灰概述  ..  9 

1.2.1 设置吹灰器的必要性..  9 

1.2.2 现有炉膛吹灰器  9 

1.2.3 吹灰效果比较  10 

2  理论基础  .  12 

2.1 冰丸除灰.  12 

2.2  FLUENT 简介  13 

2.2.1 FLUENT 的功能及特点  ..  13 

2.2.2 FLUENT 的分析过程.  14 

2.3 ANSYS 简介..  16 

2.4 本文的主要工作    16 

3 模拟思路与设计  18 

3.1 传热和应力分析模型  ..  18 

3.2 模拟设计    18 

3.2.1 fluent 软件模拟    18 

3.2.2 ANSYS 软件模拟  .  19 

3.2.3 VB数值模拟  .  21 

4 实验数据及处理  22 

4.1 fluent 数据处理  22  ANSYS冰丸穿越高温炉膛的传热过程模拟:http://www.751com.cn/zidonghua/lunwen_66648.html

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