The stratospheric airship is affected by the alternating high and low temperatures, the ozone, the ultraviolet radiation and other harsh conditions in the stratosphere environment. This paper studies the crack tip opening displacement (CTOD) fields and the strain distribution test method for the strain field in the stratospheric airship envelope material by uni-axial tensile experiments and the digital speckle correlation method (DSCM). For tearing tests of single edge notched (SEN) specimens, the initial weft crack is prefabricated to a length of 20 mm, and the typical brittle fracture is observed during the crack propagation process and the material specimen deformation field varies in a manner of steps. The calculation results of the displacement and the strain of the weft and warp fibers show that the mode I crack tip deformation field is accurately evaluated by the DSCM, which also displays the initial crack propagation law and the crack evolution characteristics of an SEN crack tip. The crack tip deformation curves for a large scale yielding length is obtained for the design and the deformation test of the high performance stratospheric airship envelope material.
LIU Longbin, LI Xue, LÜ Mingyun, MI Panpan, CAO Shuai
. Mode I Crack Tip Deformation Field for Stratopheric Airship Envelope[J]. Science & Technology Review, 2014
, 32(18)
: 15
-21
.
DOI: 10.3981/j.issn.1000-7857.2014.18.001
[1] 姚伟, 李勇, 王文隽, 等. 美国平流层飞艇发展计划和研制进展[J]. 航 天器工程, 2008, 17(2): 69-75. Yao Wei, Li Yong, Wang Wenjun, et al. Development plan and research progress of stratospheric airship in USA[J]. Spacecraft Engineering, 2008, 17(2): 69-75.
[2] 王兆希, 窦宝峰, 逄型召. 平流层浮空器用柔性复合材料的断裂性能[J]. 复合材料学报, 2011, 28(2): 211-216. Wang Zhaoxi, Dou Baofeng, Pang Xingzhao. Fracture properties of flexible composites from aerostat[J]. Acta Materiae Compositae Sinica, 2011, 28(2): 211-216.
[3] 徐斌, 颜银标. 断裂韧度CTOD评定技术的现状及应用[J]. 材料导报, 2012, 26(11): 124-129. Xu Bin, Yan Yinbiao. The overview of assessment technique of CTOD experiment and its application[J]. Materials Review, 2012, 26(11): 124-129.
[4] 万琳辉, 曹平, 黄永恒, 等. 岩石亚临界裂纹扩展及其应用研究[J]. 科 技导报, 2010, 28(9): 42-46. Wan Linhui, Cao Ping, Huang Yongheng, et al. Subcritical crack growth of rocks and its applications[J]. Science & Technology Review, 2010, 28(9): 42-46.
[5] 张亚, 强洪夫, 杨月诚. 复合型裂纹小范围屈服下裂尖塑性区统一解[J]. 机械工程学报, 2007, 43(2): 50-54. Zhang Ya, Qiang Hongfu, Yang Yuecheng. Unified solutions to mixed mode crack tip under small scale yielding[J]. Chinese Journal of Mechanical Engineering, 2007, 43(2): 50-54.
[6] 刘保琮, 李勇. 韧性金属裂纹尖端损伤区内应变场测量——数字散斑 相关法应用[J]. 实验力学, 1993, 8(1): 11-17. Liu Baochen, Li Yong. Measurement of strain field in damage zone around crack-tip—Appliacation of digital[J]. Journal of Experiment Mechanics, 1993, 8(1): 11-17.
[7] 代树红, 马胜利, 潘一山, 等. 数字散斑相关方法测定岩石I型应力强 度因子[J]. 岩石力学与工程学报, 2012, 31(12): 2501-2507. Dai Shuhong, Ma Shengli, Pan Yishan, et al. Evaluation of mode I stress intensity factor of rock utilizing digital speckle correlation method[J]. Chinese Journal of Rock Mechanics and Engineering, 2012, 31(12): 2501-2507.
[8] Bizeul M, Bouvet C, Barrau J J, et al. Fatigue crack growth in thin notched woven glass composites under tensile loading. part II: Modelling[J]. Composites Science and Technology, 2011, 71(3): 297-305.
[9] Kim S C, Kim J S, Yoon H J. Experimental and numerical investigations of mode I delamination behaviors of woven fabric composites with carbon, Kevlar and their hybrid fibers[J]. International Journal of Precision Engineering and Manufacturing, 2011, 12(2): 321-329.
[10] 陈华. 基于数字散斑相关方法的视觉变形测量技术研究[D]. 哈尔 滨: 哈尔滨工业大学, 2008. Chen Hua. Study of vision deformation measurement technologies based on digital speckle correlation method[D]. Harbin: Harbin Institute of Technology University, 2008.
[11] Sutton M A, Orteu J J, Schreier H. Image correlation for shape, motion and deformation measurements: Basic concepts, theory and applications[M]. Springer, 2009: 75-212.
[12] 樊雪松. 数字散斑相关方法研究[D]. 天津: 天津大学, 2004. Fan Xuesong. Study of digital speckle correlation method[D]. Tianjin: Tianjin University, 2004.
[13] ChenZX, LiangJ, GuoC.Applicationofdigitalspecklecorrelation method to deformation measurement[J]. Optics and Precision Engineering, 2011, 19(7): 1480-1485.
[14] Meng L B, Jin G C, Yao X F. Application of iteration and finite element smoothing technique for displacement and strain measurement of digital speckle correlation[J]. Optics and Lasers in Engineering, 2007, 45(1): 57-63.
[15] 柴兴华. 结合数字散斑干涉和数字图像相关的三维形变测量研究[D]. 北京: 北京信息科技大学, 2010. Chai Xinghua. Combined with digital speckle pattern interferometry and digital image correlation of three-dimensional deformation measurement study[D]. Beijing: Beijing University of Information Science and Technology, 2010.
[16] 曹旭, 王伟志, 顾正铭. 平流层浮空器蒙皮材料力学性能细观分析[C]//2008 年中国浮空器大会论文集. 长沙: 中国航空学会, 2008: 290-295. Cao Xu，Wang Weizhi, Gu Zhengming. Study on the mcrocosmic mechanical property of stratosphere airship composite envelope[C]//Proceesding of Chinese Aerstats Conference 2008. Changsha: China Aviation Institute Press, 2008: 290-295.
[17] American Society for Testing and Materials. ASTM D1004-2009 standard test method for tear resistance (graves tear) of plastic film and sheeting[S]. New York: American Society for Testing and Materials, 2009.
