Energy absorption mechanism of hydrophobic silica gel particles
ZHAO Peng1 YU Muchun2 CHEN Qian1
1.State Key Laboratory of Mechanics and Control of Mechanical Structure, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China；
2. China academy of launch vehicle technology, Beijing 100076, China
Abstract：Hydrophobic silica gel is a shock energy absorption buffer medium consisting of water and hydrophobic silica gel particles covered with micro-pores. It is sealed in a compressible hydraulic cylinder to form a hydrophobic silica gel buffer. During impact processes, water molecules invade and escape from hydrophobic micro-pores to realize energy storage, conversion and dissipation. Based on Laplace-Washburn equation and the contact angle hysteresis model, the process of water molecules invading and escaping from hydrophobic micro-pores was studied to establish hydrophobic silica gel’s mechanical model. Quasi-static tests were used to verify this mechanical model, and according to the actually measured force-displacement curve, the energy-dissipating efficiency of hydrophobic silica gel was calculated. The results showed that the theoretical results are better consistent to test ones; hydrophobic silica gel reveals a larger hysteretic phenomenon in loading and unloading processes, it is an ideal energy-absorbing material; if the design is appropriate, hydrophobic silica gel has excellent buffering performance.
[1] 缪宏, 左敦稳, 汪洪峰,等. 冲击载荷对飞机起落架螺纹连接的影响[J]. 振动与冲击, 2010, 29(2):208-211.
MIAO Hong, ZUO Dun-wen, WANG Hong-feng, et al. Effect of impact load on threaded connection of an aircraft landing gear[J]. Journal of Vibration and Shock, 2010, 29(2):208-211.
[2] 雷正保, 钟志华, 李岳林. 汽车碰撞过程中乘员冲击响应的分析方法及应用[J]. 中国公路学报, 2001, 14(2):115-119.
LEI Zheng-bao, ZHOHG Zhi-hua, LI Yue-lin. Study of analysis procedure for impact response of occupant during vehicle crash and its application[J]. China Journal of Highway and Transport, 2001, 14(2):115-119.
[3] 张翠霞, 陈前, 滕汉东. 混合介质缓冲器的动力学特性及缓冲效果研究[J]. 振动与冲击, 2010, 29(1): 178-182.
ZHANG Cui-xia, CHEN Qian, TENG Han-dong. Study on Dynamic Properties of SALiM Shock Absorber[J]. Journal of Vibration and Shock, 2010, 29(1): 178-182.
[4] Soulard M, Patarin J, Eroshenko V, et al. Molecular spring or bumper: A new application for hydrophobic zeolitic materials[J]. Studies in Surface Science and Catalysis, 2004, 154(04):1830-1837.
[5] Ryzhikov A, Khay I, Nouali H, et al. High pressure intrusion–extrusion of electrolyte solutions in aluminosilicate FAU and *BEA-type zeolites[J]. Microporous and Mesoporous Materials, 2016, 221:1-7.
[6] 余慕春，陈前，高雪，等. 分子弹簧的隔振机理与力学性能研究[J]. 力学学报，2014, 46(4): 553-560
YU Mu-chun, CHEN Qian, GAO Xue, et al. Investigation of molecular spring on vibration isolation mechanism and mechanical properties[J]. Chinese Journal of Theoretical and Applied Mechanics, 2014, 46(4): 553-560
[7] Yu M, Chen Q, Gao X. Theoretical and experimental investigation of molecular spring isolator[J]. Microsystem Technologies, 2017, 23(2): 285–292.
[8] Fadeev A Y, Eroshenko V A. Study of Penetration of Water into Hydrophobized Porous Silicas[J]. Journal of Colloid & Interface Science, 1997, 187(2): 275-282.
[9] Suciu C V, Iwatsubo T, Yaguchi K, et al. Investigation of the Water Flow Into a Mesoporous Matrix From Hydrophobized Silica Gel[C]// ASME/JSME 2004 Pressure Vessels and Piping Conference. 2004: 211-221.
[10] Lefevre B, Saugey A, Barrat J L, et al. Intrusion and extrusion of water in hydrophobic mesopores[J]. Journal of Chemical Physics, 2004, 120(10): 4927-4938.
[11] Surani F B, Kong X, Panchal D B, et al. Energy absorption of a nanoporous system subjected to dynamic loadings[J]. Applied Physics Letters, 2005, 87(16): 163111-163111-3.
[12] 张福田. 分子界面化学基础[M]. 上海：上海科学技术文献出版社，2006
ZHANG Fu-tian. Fundamentals of Molecular Interface Chemistry[M]. Shanghai: Shanghai Scientific and Technological LiteraturePress, 2006(inChinese).
[13] Suciu C V, Iwatsubo T, Deki S. Investigation of a colloidal damper.[J]. Journal of Colloid & Interface Science, 2003, 259(1):62-80.
[14] Tzanis L, Trzpit M, Soulard M, et al. High pressure water intrusion investigation of pure silica 1D channel AFI, MTW and TON-type zeolites[J]. Microporous and Mesoporous Materials, 2011, 146(1): 119-126.
[15] Suciu C V, Iwatsubo T, Yaguchi K, et al. Novel and global approach of the complex and interconnected phenomena related to the contact line movement past a solid surface fromhydrophobized silica gel[J]. Journal of Colloid & Interface Science, 2005, 283(1): 196–214.
[16] 王晓东, 彭晓峰, 陆建峰,等. 粗糙表面接触角滞后现象分析[J]. 热科学与技术, 2003, 2(3): 230-234.
WANG Xiao-dong, PENG Xiao-feng, LU Jian-feng, et al. Analysis of contact angle hysteresis on rough surfaces[J]. Journal of Thermal Science & Technology, 2003, 2(3): 230-234.
