摘要:电动水力学EHD(electro hydrodynamic)强化传热技术是一种利用电场、流场和温度场的相互作用来达到强化传热目的的主动强化传热方式。为了进一步探索外加电场对于气泡的作用,本课题针对均匀电场下气泡周围电场分布状况进行研究。选用了R134a工质,采用ANSYS计算软件,编程求解出不同电场作用下气泡周围场强分布特性。分别向上级板施加30kv,40kv,50kv的直流高压电场,对单个气泡附壁、脱离及多个气泡生成并部分脱离时电场分布特性进行了数值模拟。电场使气泡行为特征和运动规律发生改变,从而改变流场结构可实现传热强化,所以气泡有着核心纽带作用,气泡行为及运动规律等内容的研究,成为电场强化传热技术研究的难点和重点。35897 毕业论文关键词:电动水力学;气泡;均匀电场;数值模拟;电场特性
Effect on Bubbles in Electric Field in R134a Working Fliuds
ABSTRACT:EHD heat transfer enhancement(electro hydrodynamic)technology is a use of electric field, flow filed and temperature field of heat transfer enhancement interaction to achieve the purpose of actively strengthening heat transfer mode. In order to further explore the role of applied electric field in bubble. This research focuses on the numerical simulation of the electric field distribution around the bubble that is under the uniform electric field. The working fluid used is R134a.ANSYS is used to simulate the electric field distribution of the bubble under different uniform electric field. The top plate is respectively exerted 30kv,40kv and 50kv direct-current high voltage electric field, the simulations is carried out when a bubble attaches, departs or when the formation with partial departure of several bubbles. Electric field makes the bubble behavior characteristics and the motion the low of change, which changes the flow field structure can realize heat transfer strengthen, so bubbles play a core link function, the bubble behavior and movement low, etc, become a electric field strengthening. The research emphasis and difficulty of heat transfer technology.
KEYWORDS:EHD(electro hydrodynamic);bubbles;uniform electric field; numerical simulation;electric characteristics
目录 2
1绪论 1
1.1 课题选择的目的和意义 1
1.2 强化沸腾传热技术的研究历程 1
1.3 对强化沸腾传热技术的展望 3
1.4 沸腾强化传热技术的种类 3
1.4.1池沸腾强化传热技术 3
1.4.2流动沸腾强化传热技术 3
1.5 影响沸腾传热的因素 4
2强化沸腾换热理论基础 5
2.1 EHD强化传热机理 5
2.2 EHD强化传热的优点 7
2.3 不同工质对EHD强化换热的影响 8
3 ANSYS软件的应用 10
3.1 ANSYS软件的简介 10
3.1.1 ANSYS软件的基本知识 10
3.1.2 ANSYS软件的特点 11
3.1.3前处理模块 11
3.1.4 后处理模块 11
3.1.5 分析计算模块 11
3.2 电磁场有限元分析简介 12
3.2.1 有限元法的简介和发展 13
3.2.2 有限元的分析 13
3.3 有限元的计算步骤 15
3.3.1 构建模型 15
3.3.2 施加载荷计算 16
3.3.3 求解 16
3.3.4 后处理 17
4电场作用下工质对气泡的影响 18