摘要
风能利用的主要方式就是风力发电。而在风力机系统当中,叶片又是必不可少的部分,叶片的结构和强度对风力发电机的可靠性起决定作用。在风力机系统中,复合材料叶片由于有着一般金属材料叶片无法比拟的优势,开始受到重视。本文针对形状记忆合金(SMA)复合材料叶片的结构动力学问题进行了初步的研究探索。
首先,介绍了SMA的主要力学行为以及描述其力学行为的本构关系模型,给出了SMA回复力和马氏体含量随温度变化的关系曲线。在采用弯扭耦合梁理论建立风力机复合材料叶片的自由振动方程的基础上,通过计算分析了由NiTi/石墨/环氧树脂粘合而成的复合材料夹芯结构臂梁简化叶片模型固有振动特性。根据拉格朗日方程建立考虑复合材料叶片旋转刚体运动的振动方程,采用Galerkin法建立了广义坐标表示的弯扭耦合叶片的低阶固有振动分析模型。数值分析显示出复合材料的铺层方式和铺层角、SMA含量、温度以及风力机叶片旋转角速度对复合材料风力机叶片的固有频率和振型的影响。
根据典型截面结构模型和准定常流的气动力模型,建立了叶片气动弹性稳定性的分析方法。分别计算了不同风速下风力机叶片运动时的特征值,对比分析了叶片运动的稳定性,然后利用龙格-库塔法进行验证。
最后,采用ANSYS有限元分析软件对风力机复合材料叶片的固有振动特性进行了仿真。
The main form of wind energy is the wind power generation. The blade is the essential part in the wind turbine system.The structure and the intensity of the blade play a decisive role to the reliability of the wind turbine generator. Because of the superiority that the common metallic blade can not compare with, the composite blade becomes more and more popular in the wind turbine system. In this paper, the structural dynamics issues about the blade of SMA composite materials are studied.
First of all, the main mechanic behavior of the SMA and the constitutive relational model is introduced in this paper, which describes its mechanic behavior.The curve on which the constrained recovery stress of the SMA and the content of the Martensite change with the temperature, are also given. On the basis of the free vibration equation of the composite wind turbine blades which is developed using the beam theory about the coupling of the bending and torsion, the natural vibration characteristics of the blade of composite sandwich material, which is made of the NiTi/graphite/epoxy resin are investigated. The vibration equation of the composite rotating blade is formulated according to the Lagrange equation. The lower-order natural vibration analysis model is also established, which couples the bending and torsion, in the generalized coordinates is also derived by the method of Galerkin. The numerical results show the effect of the composite ply sequences, the ply angle, SMA content, temperature and the rotational angular velocity on the natural frequency and vibration mode of the composite wind turbine blades.
According to the classic section structural model and quasi steady flow aerodynamic model, the blade aeroelastic stable method is presented. And the eigenvalues under different wind speed are calculated, when the wind turbine blade rotates. The results are also compared with the results by Runge-Kutta method blade aeroelastic stability, agreement between results is verified.
Finally, the natural vibration characteristics of composite wind turbine blade are it simulated by the ANSYS finite element analysis software.
引文
1.吴新年,刘全根.风能-21世纪人类理想的替代能源[J].中国科学院资源环境科学信息中心1999年研究报告,1999,32(1):51-53
2.Thomas Ackermann,Lennart soder.Wind energy technology and current status:a review[J].Renewable.and Sustainable Energy Reviews,2000,(4):315-374
3.钟方国.风力发电发展现状及其复合材料的应用[J].热固性树脂,2006,21(8):16-21
4.施鹏风.风力发电在中国的现状和前景[J].水利发电学报,1998,(3)-14
5.张正敏.中国风力发电经济激励政策[M].北京:中国环境科学出版社,2002
6.童帮树.一种巨型风力机的设想[J].农村能源,1997,(3):8-10
7.谢晓芳,卞子罕.国外风力机叶片材料的进展[J].玻璃钢,2006,(4):21-24
8.李本立.风力机结构动力学[M].北京:北京航空航天大学出版社,1999
9.贺德馨等.风工程与工业空气动力学[M].北京:国防工业出版社,2006
10.刘晓燕.风力机叶片设计和稳定性分析[D].西安:西北业大学硕士论文,2004
11.黄世民.智能材料的研究与展望[J].航空科学技术,1999,(1):22-24
12.刘福顺.形状记忆合金在约束状态下力学行为的研究[J].功能材料,1996,(1):439-442
13.王征.智能机构中的形状记忆合金性能研究[J].功能材料,1996,(1):476-479
14.霍永忠.NiTi丝拉伸的物理模型及数值模拟[J].功能材料,1996,(1):488-492
15.熊克.镍钛形状记忆合金丝的性能测试分析[J].南京航空航天大学学报,1999,31(4):464-468
16.徐祖耀等.形状记忆材料[M].上海:上海交通大学出版社,2000
17.赵连城.合金的形状记忆效应与超弹性[M].北京:国防工业出版社,2002
18.杨大智.智能材料与智能系统[M].天津:天津大学出版社,2002
19.李玲.NiTi合金材料力学性能的测试与分析[J].太原理工大学学报,2002,33(1):13-15
20.Brandon D,Rogers R.C.Constitutive laws for the psedudo-elastic materials[J].Journal of Intelligent Material System and Structures,1992,(3):255-267
21.李忠宪.应用SMA复合橡胶支座的桥梁隔震[J].地震工程与工程振动,2002,(2): 143-148
22.王社良.形状记忆合金拉索被动控制结构地震响性分析[J].土木工程学报,2000,33(1):56-62
23.Tanaka K.A.Thermomechanicai sketch of shape memory effect:one-dimensional tensile behavior[J].Res Mechanical,1986,11(8):251-263
24.Liang C.,Rogers C.A.One-dimensional thermomechanical constitutive relations for shape memory materials[J].Journal of Intelligent Material System and Structures,1990,(1):207-234
25.Brinson L.C.One-dimensional constitutive behavior of shape memory alloys:Thermomechanical derivation with non-constant material functions and redefined martensite internal variable[J].Journal of Intelligent Material System and Structures,1993,(4):229-242
26.Weijia Tang,Roll Sandstrom.The material parameters in constitutive relations for NiTi shape memory alloys[J].Journal of Applied Biomechanics,1995,(10):26-35
27.刘淑红,杜彦良.形状记忆合金的应力-应变-温度关系[J].功能材料,1996,(1):461-464
28.刘淑红,杜彦良.形状记忆合金相变过程中马氏体含量的表征[J].材料科学与工艺,1986,(2):13-16
29.王兴光,钟伟芳.镍钛合金增强梁的有限元法[J].华中理工大学学报,1999,27(2):43-45
30.邹静.含形状记忆合金纤维的复合材料层合板的弯曲及其自由振动的有限元分析[J].固体力学学报,2000,21(1):27-32
31.S.Timoshenko,S.Woinowsky-Krieger.Theory of Plate and Shells[M].New York:McGraw-Hill,1959
32.沈观林.复合材料力学[M].北京:清华大学出版社,2006
33.Banerjee J R.Explicit analysis expressions for frequency equation and mode shape of composite beams[J].Int.J.Solids and Structures,2001,(38):2415-2426
34.Weisshaar W A,Foist B L.Vibration tailoring of advanced composite lifting surface[J].J.Aircraft,1985,(22):141-147
35.赵永辉,胡海岩.大展弦比夹芯翼大攻角颤振分析[J].振动工程学报,2004,17(1):25-30
36.Zhong Z W,Mei C.Finite element vibration analysis of composite plates with embedded shape memory alloy fibers at elevated temperatures[C].Design Engineering Technical Conference,1998,84(3):675-684
37.Birman V.Review of mechanics of shape memory alloy structures[J].Appl Mech Rev,1997,50(11):629-643
38.Xue M B,Song G.Adaptive control of vibration wave propagation in cylindrical shell using SMA wall joint[J].J of Sound and Vibration,2004,(278):307-326
39.Li Jun,Hua Hongxing,Shen Rongying.Dynamic finite element method for generally laminated composite beams[J].Journal of Mechanical Sciences,2007,(9)
40.Park JS,etal.Thermal post-buckling and flutter characteristics of composite plates embedded with shape memory alloy fibers[J].Composites:Part 8,2005,36:627-636
41.季文美.机械振动[M].北京:科学出版社,1985
42.方同.振动理论及应用[M].西安:西北工业大学出版社,1998
43.张锦.叶轮机振动模态分析理论及数值方法[M].北京:国防工业出版社,2001
44.周盛.叶轮机气动弹性力学讨论[M].北京:国防工业出版社,1989
45.Dowell E.H.气动弹性力学现代教程[M].北京:北航出版社,199l
46.R.Gasch,J.Twele.Wind Power Plants[J].London:James-James,2002,(2):18-22
47.刘虎平.风力机叶片设计和颤振分析[D].西安:西北工业大学硕士论文,2005
48.张锦,刘小平.叶轮机振动模态分析理论及数值方法[M].北京:国防工业出版社,2001
49.信伟平.风力机旋转叶片动力特性及响应分析[D].汕头:汕头大学硕士学位论文,2005
50.赵先琼,杨晓红.ANSYS有限元分析与20节点块单元[J].岳阳师范学院学报,2001,14(3):29-31
51.蓝宇,张连杰.大型有限元分析软件ANSYS[J].应用科技,2000,(6):11-15
52.刘国庆,杨庆东.ANSYAS工程应用教程机械篇[M].北京:中国铁道出版社,2003
53.张胜民.基于有限元软件ANSYS7.0的结构分析[M].北京:清华大学出版社,2003
54.叶先磊,史亚杰.ANSYS工程分析软件实例[M].北京:清华大学出版社,2003
55.罗高作,王平.ANSYS及结构分析应用[J].黄石高等专科学校学报,2002,18(3):26-28
56.邵蕴秋.ANSYS8.0有限元分析实例导航[M].北京:北京铁道出版社,2004
57.博嘉科技.有限元分析软件--ANSYS融会与贯通[M].北京:中国水利水电出版社,2002
58.李黎明.Ansys有限元分析使用教程[M].北京:清华大学出版社,2005
59.李顺林,王兴业.复合材料结构设计基础[M].武汉:武汉工业大学出版社,1993
60.宋佳明,周玉,雷廷权.复合材料设计的回顾与展望[J].固体火箭技术,1997,(4):53-60
61.张桂江.ANSYS在复合材料结构仿真与设计中的应用[J].陕西理工学院学报,2005,21(9):33-35
62.孟志华.ANSYS复合材料仿真分析及其在航天领域的应用[J].中国航空报,2004,(2):36-38
63.李涛.ANSYS在复合材料应力分析中的应用[J].计算机应用技术,2006,33(12):47-48