第一个书签之前
摘 要
Abstract
第一章 绪论
1.1 研究背景及意义
1.2 国内外研究现状
1.2.1 低温空化流数值模拟研究
表1-1 水、液氮和液化天然气的部分物性参数表[5]
Fig.1-1 Saturation and liquid/vapor density ratio curves of water, liquid nitrogen, liquefied natural gas
1.2.2 低温空化流的实验研究
1.3 课题的研究内容
第二章 考虑热力学效应空化模型修正与评估
2.1 控制方程
2.1.1 基本控制方程
2.1.2 湍流模型
2.1.3 空化模型
2.1.4 壁面函数
2.2 考虑热力学效应的空化模型修正
2.2.1 添加热力学效应项的修正
2.2.2 热力学物性参数的修正
2.3 数值模型于求解器中的计算实现
2.3.1 原始空化模型的计算实现
2.3.2 修正空化模型的计算实现
2.4 本章小结
第三章 不同温度水空化的空化流数值模拟及其空化特性
3.1 几何模型和边界条件设置
图3-1 实验段结构示意图[47]
Fig.3-1 Schematic of test section structure
图3-2 三维水体模型及边界条件
Fig.3-2 Schematic of the 3D model with water and the boundary conditions of the cases
表3-1 不同温度水空化数值模拟边界条件
Table.3-1 Boundary conditions of numerical simulation about cavitation in water with different temperature
3.2 网格划分和无关性验证
图3-3 不同网格所计算的压力系数
Fig.3-3 Pressure coefficient of different grids
表3-2 不同网格信息
Table.3-2 Information of different grids
图3-4 翼型局部网格
Fig.3-4 Grids distribution near the hydrofoil
图3-5 翼型表面y+值分布
Fig.3-5 Yplus distribution on the surface of the hydrofoil
3.3 不同空化模型在不同温度水空化中的应用
表3-3 不同温度水与水蒸汽的部分物性参数
Table.3-3 Physical parameters of water and water vapor at different temperatures
(b)50℃
图3-6 不同温度下不同空化模型模拟得到翼型吸力面的压力系数分布
Fig.3-6 Pressure coefficient on the suction surface of the hydrofoil with the different cavitation models at different temperatures
图3-7 不同空化模型模拟所得测量点压力系数的均方根误差
Fig.3-7 RMSE of pressure coefficient at pressure taps simulated with different cavitation models
表3-4 模拟所得测量点压力系数的均方根误差值
Table.3-4 RMSE of the pressure coefficient simulated at pressure taps
(a)25℃
(b)50℃
图3-8 不同温度下不同空化模型模拟得到翼型吸力面的蒸汽体积分数
Fig.3-8 The vapour volume fraction along the suction surface of the hydrofoil with the different cavitation models at different temperatures
图3-9 不同空化模型模拟所得翼展中截面空穴尺度及面积
Fig.3-9 The cavity length and cavity area on the cross section at middle of wingspan simulated with different cavitation models
3.4 修正空化模型在不同温度水空化中的应用
(a)25℃
(b)50℃
图3-10 不同温度下不同修正空化模型模拟得到翼型吸力面的压力系数分布
Fig.3-10 Pressure coefficient on the suction surface of the hydrofoil with the different modified cavitation models at different temperatures
图3-11 不同修正的空化模型模拟所得测量点压力系数的均方根误差
Fig.3-11 RMSE of pressure coefficient at pressure taps simulated with the different modified cavitation models
表3-5 模拟所得测量点压力系数的均方根误差值
Table.3-5 RMSE of the pressure coefficient simulated at pressure taps
(a)25℃
(b)50℃
图3-12 不同温度下不同修正空化模型模拟得到翼型吸力面的蒸汽体积分数
Fig.3-12 The vapour volume fraction along the suction surface of the hydrofoil with the different modified cavitation models at different temperatures
图3-13 不同修正空化模型模拟所得翼展中截面空穴尺度及面积
Fig.3-13 The cavity length and cavity area on the cross section at middle of wingspan simulated with different modified cavitation models
3.5 热力学效应对不同温度水空化的影响
3.5.1 压力及温度分布对比分析
图3-14 不同温度下模拟所得翼型吸力面压降及分布云图
Fig.3-14 The pressure difference on the suction surface of the hydrofoil simulated at different temperatures
图3-15 不同温度下模拟所得翼型吸力面温降及分布云图
Fig.3-15 The temperature difference on the suction surface of the hydrofoil simulated at different temperatures
3.5.2 空泡形态及空化强度对比分析
图3-16 不同温度下模拟所得翼型吸力面蒸汽体积分数及分布云图
Fig.3-16 The vapour volume fraction on the suction surface of the hydrofoil simulated at different temperatures
图3-17 不同温度下模拟所得翼型吸力面当地空化数及分布云图
Fig.3-17 The local cavitation number on the suction surface of the hydrofoil simulated at different temperatures
3.5.3 相间质量传输特性对比分析
图3-18 不同温度下模拟所得液汽相间质量传输速率分布云图
Fig.3-18 The water-water vapour mass transfer rate on the suction surface of the hydrofoil simulated at different temperatures
3.6本章小结
第四章 低温流体空化的两相流数值模拟及其空化机理
4.1 几何模型和边界条件设置
图4-1 实验段结构[43]
Fig.4-1 Test section structure
图4-2 水翼结构[43]
Fig.4-2 Hydrofoil structure
图4-3 三维对称水体模型及边界条件
Fig.4-3 Schematic of the symmetrical 3D model with water and the boundary conditions of the cases
表4-1不同液氮中空化数值模拟边界条件
Table.4-1 Boundary conditions of numerical simulation about cavitation in nitrogen with different temperature
4.2 网格划分和无关性验证
图4-4 不同网格所计算的压力系数
Fig.4-4 Pressure coefficient of different grids
表4-2 不同网格信息
Table.4-2 Information of different grids
图4-5 水翼局部网格
Fig.4-5 Grids distribution near the hydrofoil
图4-6 水翼表面y+值分布
Fig.4-6 Yplus distribution on the surface of the hydrofoil
4.3 不同空化模型在低温流体空化中的应用
表4-3 不同温度饱和液氮液相及汽相的部分物性参数
Table.4-3 Physical parameters of nitrogen and nitrogen vapor at different temperatures
图4-7 不同空化模型模拟所得水翼表面的压力分布
Fig.4-7 Pressure on the surface of the hydrofoil with the different cavitation models
图4-8 不同空化模型模拟所得测量点压力的均方根误差
Fig.4-8 RMSE of pressure at pressure taps simulated with different cavitation models
表4-4 模拟所得测量点压力的均方根误差值
Table.4-4 RMSE of the pressure simulated at pressure taps
4.4 修正空化模型在低温流体空化中的应用
图4-9 修正空化模型数值模拟所得水翼表面的压力分布
Fig.4-9 Pressure on the surface of the hydrofoil with the modified cavitation model
图4-10 修正空化模型数值模拟所得水翼表面的温度分布
Fig.4-10 Temperature coefficient on the surface of the hydrofoil with the modified cavitation model
图4-11 修正空化模型模拟所得水翼表面的蒸汽体积分数
Fig.4-11 The vapour volume fraction along the surface of the hydrofoil with the modified cavitation model
图4-12 Merkle空化模型模拟所得翼展中截面空穴尺度及面积
Fig.4-12 The cavity length and cavity area on the cross section at middle of wingspan simulated with Merkle cavitation models
4.5 热力学效应对低温流体空化的影响
4.5.1 压力及温度分布对比分析
图4-13 不同液氮中模拟所得水翼表面压降及分布云图
Fig.4-13 The pressure difference on the surface of the hydrofoil simulated in different liquid nitrogen
图4-14 不同液氮中模拟所得水翼表面温降及分布云图
Fig.4-14 The temperature difference on the surface of the hydrofoil simulated in different liquid nitrogen
4.5.2 空泡形态及空化强度对比分析
图4-15 不同液氮中模拟所得水翼表面蒸汽体积分数及分布云图
Fig.4-15 The vapour volume fraction on the surface of the hydrofoil simulated in different liquid nitrogen
图4-16 不同液氮中模拟所得水翼表面当地空化数及分布云图
Fig.4-16 The local cavitation number on the surface of the hydrofoil simulated in different liquid nitrogen
4.5.3 相间质量传输特性对比分析
图4-17 不同液氮中模拟所得液汽相间质量传输速率分布云图
Fig.4-17 The water-water vapour mass transfer rate on the surface of the hydrofoil simulated in different liquid nitrogen
4.6本章小结
第五章 总结与展望
5.1 总结
5.2 展望
参考文献
致谢
攻读硕士发表的学术论文及参加的科研工作