Entity

Time filter

Source Type


Li Y.-B.,Nanjing Southeast University | Li Y.-B.,Key Laboratory of Engineering Mechanics of Jiangsu Province | Zhang P.,Nanjing Southeast University | Zhang P.,Key Laboratory of Engineering Mechanics of Jiangsu Province | And 5 more authors.
Yuhang Xuebao/Journal of Astronautics | Year: 2015

Based on Finite element method-Direct boundary element method (FEM-DBEM) and Finite element method-Indirect boundary element method (FEM-IBEM) approach, the bearing cylinder-skin structural-acoustic coupling models considering onlyinternalorexternalacoustic field and both inside and outside acoustic field are established. The structural-acoustic coupling analysis under random base excitation is researched. Further, the coupled effect of internal/external acoustic field and structural-acoustic coupling on the inherent characteristics and dynamic response is analyzed with the emphasis on. Results show that coupled effect results in the decrease of its nature frequencies, but has no effect on the modal shape. Single acoustic field effect results in the increase of the nature frequencies more than both inside and outside acoustic field effect. The coupled effect also results in the overall decrease of dynamic response, but causes increase of the dynamic responsein the places where is parallel to the direction of excitation. In addition, influence of internal acoustic field on the dynamic responseis greater than the external acoustic field. ©, 2015, China Spaceflight Society. All right reserved. Source


Li Y.-B.,Nanjing Southeast University | Li Y.-B.,Key Laboratory of Engineering Mechanics of Jiangsu Province | Zhang P.,Nanjing Southeast University | Zhang P.,Key Laboratory of Engineering Mechanics of Jiangsu Province | And 4 more authors.
Zhendong Gongcheng Xuebao/Journal of Vibration Engineering | Year: 2015

Hypersonic vehicle suffers severe environment with the combination of thermal, vibration and noise during service. The coupling of structure and acoustic is one of the most concerned problems in the design stage. Based on the FEM-BEM approach, the structural-acoustic coupling analysis of a composite stiffened panel in thermal environment is conducted with three cases: (1) only the material properties change with temperature; (2) only the stiffness of panel changes with temperature due to thermal stress; (3) two kinds of influences, (1) and (2) are both considered. Results show that high temperature on panel changes its material properties which results in the decrease of its nature frequencies, the increased amplitude of the peaks shifting to lower frequency domain. The thermal stress due to high temperature reduces most of the nature frequencies, changes the modal shape, causes a significant increase in the response peaks shifting to higher frequency domain and restrains the response of acceleration. When the two kinds of influences are both considered, the response of stress and acceleration are significantly increased and decreased, respectively, with the amplitude of peak fall between the results from case (1) and (2). Temperature has little effect on the sound pressure response. ©, 2015, Nanjing University of Aeronautics an Astronautics. All right reserved. Source


Li Y.-B.,Nanjing Southeast University | Li Y.-B.,Key Laboratory of Engineering Mechanics of Jiangsu Province | Jiang D.,Nanjing Southeast University | Jiang D.,Key Laboratory of Engineering Mechanics of Jiangsu Province | And 4 more authors.
Guti Huojian Jishu/Journal of Solid Rocket Technology | Year: 2013

To ensure the structural integrity of missile cabin connections under transportation loads, a novel scheme was proposed to accurately simulate the rivets connections between two cabins of a missile. The power spectral density of stress was calculated from the stochastic analysis, based on which the fatigue life of the rivet connections was evaluated. Results show that the first vertical bending mode and the first longitudinal mode are excited during transportation. The longitudinal excitation forces make greater contribution to the dynamic stress of rivet connections. The fatigue life of the rivets at the left and right sides are shorter than that at the up and down sides. In each group of three rivets, the fatigue life of the sideward ones is shorter than the middle one. All rivets fulfill the infinite life requirements of design. Source

Discover hidden collaborations