摘要
摩阻天平是直接测量作用在飞行器模型表面摩阻的重要手段,本文介绍了一种基于压电敏感元件的压电效应进行摩阻天平设计的情况。天平主体采用悬臂梁结构,通过在悬臂梁上对称布置的压电陶瓷片进行摩阻的测量,利用压电陶瓷片的方向选择性来降低模型表面的压力对摩阻测量结果的交叉干扰。在设计中,利用有限元分析的方法,采用力电耦合模型,对天平的性能进行了评估分析。根据有限元分析的结果,设计制作了用于激波风洞试验的摩阻天平,并对摩阻天平进行了校准和风洞试验。结果表明,天平的灵敏度、频响和稳定性均能满足激波风洞摩阻测量试验的要求,通过压电陶瓷片的组合可以有效地降低模型表面分布不均匀的压力对摩阻测量输出的影响。
Skin friction plays a great role in the total drag of hypersonic vehicles, and skin friction balance is widely used to measure the skin friction of hypersonic vehicles directly. A great number of skin friction balances are developed to test the skin friction in impulse tunnels, which include strain gauge balance, piezoelectric balance, fiber optical balance, and MEMS based skin friction gauge. The design of skin friction balance based on piezoelectric ceramic is introduced in this paper. The cantilever beam structure is used in the design, the skin friction are test by the piezoelectric ceramics symmetrically stuck to the cantilever beam. The polarized orientation of the piezoelectric ceramic is used to minimize the skin friction output influenced by the flow pressure on the surface of the model. In the design, the finite element analysis by the software of ANSYS is used to evaluate the character of the skin friction balance. The analysis contains the static force analysis and mode analysis. A skin friction balance with the cantilever beam thickness of 4mm is developed according to the finite element analysis design results. The sensitivity is 0.957V/N compared with the simulation result of 1.16V/N. The first order response frequency is 2563Hz compared with the simulation result of 2746Hz. The sensitivity difference may be caused by the glue which used to stick the piezoelectric ceramic to the skin friction balance structure, and the response frequency difference may be caused by the simplified model in the ANSYS simulation. The result showed that, the sensitivity and frequency of the skin friction balance can satisfied the need of the shock tunnel skin friction measurement. The combination of the piezoelectric ceramic voltage outputs can reduce the influence of non-uniform pressure on the skin friction output.
作者
赵荣娟
吕治国
黄军
刘施然
ZHAO Rongjuan;LYU Zhiguo;HUANG Jun;LIU Shiran(Hypervelocity Aerodynamics Institute of China Aerodynamics Research and Development Center,Mianyang G21000,China)
出处
《空气动力学学报》
CSCD
北大核心
2018年第4期555-560,共6页
Acta Aerodynamica Sinica
基金
试验技术研究项目(2012SY29B0010)
关键词
压电陶瓷
摩阻天平
有限元分析
设计
piezoelectric ceramic
skin friction balance
finite element analysis
design
