高速撞壁液滴內(nèi)在瞬變特征及其規(guī)律的數(shù)值研究

第1章引言
1.1研究背景和意義
1.2液滴與壁面作用過程的研究綜述
1.2.1液滴撞擊固體壁面的模態(tài)研究總結(jié)
1.2.2液滴撞擊固體壁面的動(dòng)力學(xué)過程研究
1.2.3液滴高速撞壁問題的研究進(jìn)展
1.2.4小結(jié)
1.3高速液滴撞擊壁面過程的流動(dòng)現(xiàn)象及其物理解釋
1.3.1水錘激波
1.3.2復(fù)雜波系演化
1.3.3液滴內(nèi)的空化
1.3.4壁面侵蝕與損傷
1.3.5壁面幾何效應(yīng)
1.4相變與空化模型
1.4.1相變模型
1.4.2空化模型
1.5本書研究目的和內(nèi)容
第2章數(shù)值模型與方法
2.1可壓縮兩相流控制方程和數(shù)值方法
2.1.1控制方程
2.1.2模型的數(shù)學(xué)性質(zhì)
2.1.3控制方程的離散與求解方法
2.2物性參數(shù)的計(jì)算
2.3空化相變模型
2.3.1均質(zhì)/異質(zhì)成核空化模型
2.3.2相變過程的數(shù)值求解
2.4數(shù)值方法的驗(yàn)證
2.4.1單相激波管問題
2.4.2兩相激波管問題
2.4.3膨脹空化問題
2.4.4二維空泡瑞利潰滅問題
2.5本章結(jié)論
第3章高速液滴撞擊剛性水平壁面
3.1物理模型
3.2數(shù)值結(jié)果驗(yàn)證
3.2.1網(wǎng)格敏感性分析
3.2.2實(shí)驗(yàn)比照
3.3液滴內(nèi)部流場(chǎng)與波系演化規(guī)律
3.3.1階段——水錘激波的產(chǎn)生和脫離
3.3.2第二階段——激波的運(yùn)動(dòng)與反射
3.3.3第三階段——反射波的匯聚與空化泡產(chǎn)生
3.3.4第四階段——空化泡潰滅
3.4初始速度的影響
3.4.1撞壁液滴的幾何特性
3.4.2空化泡尺度
3.4.3潰滅激波強(qiáng)度
3.5流體物性的影響
3.5.1物性參數(shù)擬合
3.5.2結(jié)果分析與討論
3.6本章結(jié)論
第4章含空化泡液滴高速撞擊剛性水平壁面
4.1物理模型
4.2含空氣泡/蒸氣泡液滴高速撞壁過程對(duì)比分析
4.2.1動(dòng)力學(xué)過程的整體分析
4.2.2空泡的變形與潰滅機(jī)制
4.2.3水平壁面受力分析
4.3空泡尺寸與液滴初始速度的影響
4.3.1空泡潰滅時(shí)間
4.3.2潰滅峰值壓力
4.3.3壁面受力分析
4.4空泡位置的影響
4.5本章結(jié)論
第5章液滴高速撞擊曲形固體壁面
5.1物理模型
5.2撞擊液滴中受限水錘激波的演化規(guī)律
5.2.1受限水錘激波的產(chǎn)生
5.2.2水錘激波與壁面的脫離
5.2.3水錘激波的運(yùn)動(dòng)及其形態(tài)演化
5.3空化及其演化規(guī)律
5.3.1液滴內(nèi)部的均質(zhì)空化
5.3.2壁面附近的異質(zhì)空化
5.4壁面受力規(guī)律
5.5三維效應(yīng)討論
5.6本章結(jié)論
第6章全書總結(jié)與展望
6.1全書總結(jié)
6.2研究展望
參考文獻(xiàn)
在學(xué)期間發(fā)表的學(xué)術(shù)論文與研究成果
致謝
 
 
Contents
Contents
Chaper 1Introduction1
1.1Background & Motivation1
1.2Literature Review of Droplet Impingement Problem2
1.2.1Different Outcomes of Droplet Impingement3
1.2.2Kinetic Processes of Droplet Impingement6
1.2.3Research Progress of HighSpeed Droplet 
Impingement8
1.2.4Literature Summary11
1.3Flow Mechanics Study of HighSpeed Droplet Impingement12
1.3.1WaterHammer Shock Wave12
1.3.2Evolution of Complex Wave System13
1.3.3Cavitation Phenomena in the Droplet15
1.3.4Erosion of the Impinging Wall16
1.3.5Surface Geometric Effect17
1.4Research of Phase Transition & Cavitation Model18
1.4.1Phase Transition Model18
1.4.2Cavitation Model21
1.5Research Purpose23
Chapter2Mathematical Model & Computational Methodology25
2.1Twophase Compressible Model25
2.1.1Governing Equations25
2.1.2Mathematical Properties of the Model27
2.1.3Discretization of the Governing Equation28
2.2Physical Parameters Calculation33
2.3Cavitation & Phase Transition Model34
2.3.1Homogeneous/Heterogeneous Nucleation Cavitation
Model34
2.3.2Numerical Simulation of Phase Transition Process36
2.4Numerical Validation40
2.4.1Sod Problem40
2.4.2TwoPhase Shock Tube Problem41
2.4.3Real Cavitation43
2.4.4Spherical Bubble Collapse44
2.5Chapter Summary46
Chapter 3Highspeed Droplet Impingement on the Rigid Flat Wall47
3.1Physical Model47
3.2Validation of Numerical Results48
3.2.1Grid Sensitivity Analysis48
3.2.2Comparison With Experimental Results50
3.3Transient Characteristics Inside the Impinging Droplet54
3.3.1The First Stage—Generation and Detachment of
Shock Wave55
3.3.2The Second Stage—Propagation and Reflection of
Shock Wave57
3.3.3The Third Stage—Wave Convergion and Cavitiation
Generation61
3.3.4The Fouth Stage—Cavitation Collapse64
3.4Influence of Initial Velocity66
3.4.1Geometric Properties of Droplets66
3.4.2Size of the Cavitation Zone69
3.4.3Intensity of Collapse Waves70
3.5Influence of Fluids Physical Properties72
3.5.1Physical Parameter Fitting72
3.5.2Results Analysis and Discussion73
3.6Chapter Summary78
Chaper 4Highspeed Impingement of Droplet Embedded With Cavity80
4.1Physical Model80
4.2Results Comparison of Droplets Embedded With Different
Cavities81
4.2.1Analysis of the Whole Dynamic Processes83
4.2.2Deformation and Collapse Mechanism of Embeding
Cavities88
4.2.3Stress Bearing Analysis of Impinging Wall94
4.3Influence of Cavity Size and Initial Velocity95
4.3.1Collapse Time of Embeding Cavities96
4.3.2Peak Collapse Pressure98
4.3.3Wall Stress Analysis99
4.4Influence of Cavitys Initial Position101
4.5Chapter Summary104
Chapter 5HighSpeed Droplet Impingement on the Rigid Curved Wall106
5.1Physical Model106
5.2Analysis of Confined Shock Waves Under Different Curved
Wall107
5.2.1Generation of Shock Wave107
5.2.2Detachment of Shock Wave110
5.2.3Waveform Evolution114
5.3Cavitation Inside Droplet114
5.3.1Focusing Homogeneous Cavitation115
5.3.2NearWall Heterogeneous Cavitation116
5.4Stress Bearing Analysis of Different Curved Wall120
5.5Discussion of Three Dimensional Effect121
5.6Chapter Summary125
Chapter 6Conclutions127
6.1Summary127
6.2Prospect128
References129
Published Academic Papers146
Acknowledgements147