ANSYS+R124工质作用下电场对气泡的作用
时间:2018-04-14 12:52 来源:毕业论文 作者:毕业论文 点击:次
| 摘要: 为了探明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R124 工质，利用 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。分别向上极板施加 15kv,20kv,25kv 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。结果表明，气泡周围电场分布不再均匀，随着施加的直流高压电场的增大，场强也逐渐增大，随着两侧的场强增大，而靠近气泡顶部及底部附近的场强降低。随着气泡数量的增多，场强对气泡的作用相应变弱。场强使气泡周围电场特性发生改变，使 EHD强化效果增强。 21202 关键词：水电动力学；均匀电场；电场特性；气泡 R124 Refrigerant under the Action of an Electric Field on the Bubble Abstract：In order to proven the role of the applied electric field for the bubbles. 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 R124. Ansys is used to simulate the electric field distribution of the bubble under different uniform electric field .The top plate is respectively exerted 15kv,20k vand 25kv 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. The results indicate that the electric field distribution around the bubble is no longer uniform .The field strength also is increased with the increase of the applied direct-current high voltage electric field, and the electric fields of the two sides are enhanced while near the top and bottom areas the electric fields decrease. As the numbers of bubbles become more, the effect of electric field on bubbles becomes weaker. So the conclusion is reached that the electric field distribution around the bubbles will be changed by the electric field and thus will enhance the effect of EHD. Key words: electrohydrodynamics; uniform electric field; electric characteristics; bubbles 目 录 目录 1 绪论 . 1 1.1课题选择依据及研究意义 . 1 1.2 国内外发展概况 . 1 1.2.1 国内 . 1 1.2.2 国外 . 2 1.3 强化传热的途径 . 2 1.3.1增强传热系数 3 1.3.2 采用高效能的传热面,增大传热面积 3 1.3.3 加大平均温差 . 3 1.4 强化沸腾传热技术的研究历程 . 3 2 EHD 强化沸腾换热理论基础 . 6 2.1 EHD强化传热机理 . 6 2.1.1 汽泡在电场中所受到的力 . 8 2.1.2 EHD对汽液界面的作用 . 10 2.1.3 EHD对接触角和表面张力的改变 . 11 2.2 EHD强化沸腾换热的基本方程 11 2.2.1 存在一个汽泡的均匀电场分析 12 2.2.2 存在多个汽泡的非均匀电场模拟 12 2.2.3 电场及电场力的数值解 12 2.3 EHD强化沸腾换热的数学模型 . 13 3 ANSYS 软件应用 15 3.1 ANSYS软件简介 15 3.2 ANSYS软件功能 15 3.2.1 前处理 15 3.2.2 加载求解 17 3.2.3 后处理 17 3.2.4 ANSYS处理应用技巧 . 18 3.3有限元法的计算步骤 18 3.3.1 构建模型 18 3.3.2 施加载荷计算 19 3.3.3 求解 19 3.3.4 后处理 20 4 电场作用下 R124 对气泡的影响 . 21 (责任编辑：qin) |