不同结构特征悬臂梁的振动影响实验研究

摘要 (Ⅰ)

ABSTRACT (Ⅱ)

目录 (Ⅳ)

CONTENTS (Ⅶ)

第一章绪论 (1)

1.1 研究背景和意义 (1)

1.2悬臂梁相关振动国内外研究现状 (3)

1.3粘弹性阻尼技术的研究现状 (6)

1.4主要研究内容 (8)

第二章悬臂梁振动模型基本理论 (9)

2.1悬臂梁的模型简化分析 (9)

2.1.2振动系统微分方程 (9)

2.1.2固有频率和主振型 (11)

2.2欠阻尼振动系统微分方程的解及特性 (13)

2.2.1振动系统微分方程的欠阻尼的解 (13)

2.2.2欠阻尼的振动特性分析 (14)

2.3结构振动的阻尼模型 (14)

2.3.1瑞利阻尼 (15)

2.3.2阻尼比 (16)

2.4本章小结 (16)

第三章振动响应的实验及数据处理 (17)

3.1悬臂梁振动试验台的搭建 (17)

3.1.1实验装置 (17)

3.1.2实验试件 (18)

3.2实验原理及主要仪器 (18)

3.2.1实验原理 (18)

3.2.2电涡流传感器原理及特点 (19)

3.2.3测试系统的操作软件 (21)

3.3实验步骤 (22)

3.4曲线拟合 (25)

3.4.1最小二乘法原理及其计算 (25)

3.4.2非线性拟合 (26)

3.4.3麦夸特算法 (27)

3.5实心悬臂梁响应参数的求解 (28)

3.5.1参数拟合过程 (28)

3.5.2拟合结果及评价指标 (28)

3.5.3实验参数拟合计算 (29)

3.5.4结构固有频率有限元分析 (30)

3.5.5实验误差分析 (30)

3.6本章总结 (31)

第四章不同结构特征的悬臂梁振动响应实验 (32)

4.1不同长度槽孔结构对悬臂梁振动响应的影响 (32)

4.1.1悬臂梁槽孔切割加工 (32)

4.1.2实验试件 (32)

4.1.3载荷与槽孔方向相同时悬臂梁振动响应实验 (33)

4.1.4载荷与槽孔方向垂直时悬臂梁振动响应实验 (35)

4.1.5槽孔悬臂梁实验结果数据 (37)

4.1.6不同方向载荷悬臂梁槽孔长度对刚度影响分析 (38)

4.1.7不同方向载荷悬臂梁槽孔长度对特征频率影响分析 (38)

4.1.8不同方向载荷悬臂梁槽孔长度对阻尼影响分析 (40)

4.2孔径大小对悬臂梁振动响应的影响 (41)

4.2.1悬臂梁圆孔的加工 (41)

4.2.2实验试件 (41)

4.2.2作用力方向与圆孔方向相同时振动实验 (42)

4.2.3作用力方向与孔径方向不同时振动实验 (43)

4.2.4圆孔实验结果数据 (45)

4.2.5不同方向载荷悬臂梁孔径大小对刚度影响 (45)

4.2.6不同方向载荷悬臂梁孔径大小对特征频率的影响 (46)

4.2.7不同方向载荷悬臂梁孔径大小对阻尼的影响 (46)

4.3本章结论 (47)

第五章不同阻尼结构的悬臂梁振动响应实验 (48)

5.1粘弹性阻尼材料 (48)

5.1.1阻尼材料的选用 (48)

5.1.2粘弹性材料阻尼机理 (49)

5.1.3不同阻尼层结构 (50)

5.2阻尼材料的基本模型 (51)

5.3制备粘弹性层合悬臂梁 (52)

5.4不同阻尼材料对槽孔结构悬臂梁的振动实验 (53)

5.4.1塑料对槽孔悬臂梁振动响应实验 (53)

5.4.2橡胶对槽孔悬臂梁振动响应实验 (55)

5.4.3计算实验结果 (58)

5.4.4不同阻尼材料悬臂梁槽孔长度对刚度的影响 (58)

5.4.5不同阻尼材料悬臂梁槽孔长度对阻尼的影响 (59)

5.4.6不同阻尼材料悬臂梁槽孔长度对特征频率的影响 (60)

5.5槽孔长L=280mm的悬臂梁振动仿真 (62)

5.5.1槽孔悬臂梁无阻尼约束的振动仿真 (62)

5.5.2槽孔悬臂梁橡胶约束的振动仿真 (63)

5.5.3槽孔悬臂梁塑料约束的振动仿真 (65)

5.6本章总结 (66)

结论与展望 (68)

参考文献 (70)

攻读硕士学位期间发表的论文 (75)

学位论文独创性声明 (76)

学位论文版权使用授权声明 (76)

致谢 (77)

CONTENTS

ABSTRACT(Chinese) (Ⅰ)

ABSTRACT(English) (Ⅱ)

CONTENTS(Chinese) (Ⅳ)

CONTENTS(English) (Ⅶ)

Chapter 1 Introduction (1)

1.1 Research background and significance (1)

1.2 Research status of cantilever beam vibration control at home and abroad (3)

1.3 Research status of viscoelastic damping technology (6)

1.4 Main research contents (8)

Chapter 2 Basic theory of cantilever beam vibration model (9)

2.1Simplified model of cantilever beam (9)

2.1.2Differential equation of vibration system (9)

2.1.2Natural frequency and main vibration mode (11)

2.2Solution and characteristic of differential equation of damped vibration system

(13)

2.2.1The damped solution of differential equation of vibration system (13)

2.2.2Analysis of vibration characteristics of under damping (14)

2.3Damping model of structural vibration (14)

2.3.1Rayleigh damping (15)

2.3.2 damping ratio (16)

2.4Summary (16)

Chapter 3 Experiment and data processing of vibration response (17)

3.1Construction of cantilever beam vibration test bed (17)

3.1.1 Experimental device (17)

3.1.2Experimental specimen (18)

3.2Experimental principle and main instrument (18)

3.2.1Experimental principle (18)

3.2.2Principle and characteristics of eddy current sensor (19)

3.2.3Test system operating software (21)

3.3Experimental procedure (22)

3.4curve fitting (25)

3.4.1The principle of least square method and its calculation (25)

3.4.2Nonlinear fitting (26)

3.4.3Marquardt algorithm (27)

3.5Solution of response parameters of solid cantilever beam (28)

3.5.1Parameter fitting process (28)

3.5.2Fitting result and evaluation index (28)

3.5.3Fitting calculation of experimental parameters (29)

3.5.4Finite element analysis of structural natural frequency (30)

3.5.5Experimental error analysis (30)

3.6Summary (31)

Chapter 4 Study on the influence of different structural characteristics on vibration response (32)

4.1Influence of different length slot structure on the vibration response of

cantilever beam (32)

4.1.1Slot cutting of cantilever beam (32)

4.1.2Experimental specimen (32)

4.1.3Experimental study on the vibration response of cantilever beam with the

same direction of the slot (33)

4.1.4Experimental study on the vibration response of cantilever beam under

vertical load (35)

4.1.5Experimental results of slotted cantilever beam (37)

4.1.6Analysis of the influence of the length of the cantilever beam on the

stiffness of the cantilever beam (38)

4.1.7Analysis of the influence of the length of cantilever beam on the

characteristic frequency (38)

4.1.8Analysis of the influence of the length of the cantilever beam in different

directions on the damping (40)

4.2Effect of pore size on vibration response of cantilever beam (41)

4.2.1The processing of cantilever beam with different holes (41)

4.2.2Experimental specimen (41)

4.2.2Vibration experiment on the same direction as the direction of circular

hole (42)

4.2.3Vibration experiment of different direction of force and aperture (43)

4.2.4Experimental results of circular hole (45)

4.2.5Influence of aperture size of cantilever beam on stiffness in different

directions (45)

4.2.6Influence of aperture size of cantilever beam with different direction on

characteristic frequency (46)

4.2.7Influence of aperture size of cantilever beam with different direction on

damping (46)

4.3Summary (47)

Chapter 5Experimental study on vibration of cantilever beam with different damping materials (48)

5.1Viscoelastic damping material (48)

5.1.1Selection of damping materials (48)

5.1.2Damping mechanism of viscoelastic material (49)

5.1.3Damping structure of polymer damping material (50)

5.2Basic model of damping material (51)

5.3Viscoelastic laminated cantilever beam (52)

5.4Experimental study on vibration of cantilever beam with different damping

materials (53)

5.4.1Experimental study on vibration response of plastic cantilever beam (53)

5.4.2Experimental study on vibration response of rubber to slotted cantilever

beam (55)

5.4.3Calculated results (58)

5.4.4 The influence of the length of the cantilever beam on the stiffness of different

damping materials (58)

5.4.5Influence of the length of the cantilever beam with different damping

materials on damping (59)

5.4.6Influence of the length of the cantilever beam on the characteristic frequency

of different damping materials (60)

5.5 Vibration simulation of cantilever beam with long slot L=280mm .......................

(61)

5.5.1 Vibration simulation of slotted cantilever beam without damping

constraint (61)

5.5.2 Vibration simulation of slotted cantilever beam with rubber restraint (63)

5.5.3 Vibration simulation of plastic constraint on slotted cantilever beam (65)

5.6Summary (66)

CONCLUSION AND PROSPECT (68)

REFERENCE (70)

PUBLICATION DRUING STUDY (75)

ORIGINAL STATEMENT OF DEGREE THESIS (76)

AUTHORIZED STATEMENT OF COPYRIGHT (76)

ACKNOWLEDGMENTS (77)