Using the single crack solution and the regular solution of plane harmonic function, the problem of Saint_Venant bending of a cracked cylinder by a transverse force was reduced to solving two sets of integral equation...Using the single crack solution and the regular solution of plane harmonic function, the problem of Saint_Venant bending of a cracked cylinder by a transverse force was reduced to solving two sets of integral equations and its general solution was then obtained. Based on the obtained solution, a method to calculate the bending center and the stress intensity factors of the cracked cylinger whose cross_section is not thin_walled, but of small torsion rigidity is proposed. Some numerical examples are given.展开更多
The aim of this work is to propose a 3D FE model of a theoretical assembling straight bevel gear pair to analyze the contact fatigue on the tooth surface and the bending fatigue in the tooth root. Based on the cumulat...The aim of this work is to propose a 3D FE model of a theoretical assembling straight bevel gear pair to analyze the contact fatigue on the tooth surface and the bending fatigue in the tooth root. Based on the cumulative fatigue criterion and the stress-life equation, the key meshing states of the gear pair were investigated for the contact fatigue and the bending fatigue. Then, the reliability of the proposed model was proved by comparing the calculation result with the simulation result. Further study was performed to analyze the variation of the contact fatigue stress and the bending fatigue stress under different loads. Furthermore, the roles of the driving pinion and the driven gear pair were evaluated in the fatigue life of the straight bevel gear pair and the main fatigue failure mode was determined for the significant gear. The results show that the fatigue failure of the driving pinion is the main fatigue failure for the straight bevel gear pair and the bending fatigue failure is the main fatigue failure for the driving pinion.展开更多
Accurate springback prediction of wide sheet metal air bending process is important to improve product quality and ensure the precision in dimension. The definition of elastic limit bend angle was proposed. Based on c...Accurate springback prediction of wide sheet metal air bending process is important to improve product quality and ensure the precision in dimension. The definition of elastic limit bend angle was proposed. Based on cantilever beam elastic deforming theory, the geometrical parameters of forming tools, sheet thickness and the material yielding strain were derived and validated by the finite element method (FEM). Employing the degree of elastic limit bend angle, the equation for springback prediction was constructed, the results calculated fit well with experimental data. Especially for the small bend angle, the predicted results by equation were applied to conduct the springback prediction and compensation in industries and give closer correlation to the experimental data than those calculated by engineering theory of plastic bending.展开更多
文摘Using the single crack solution and the regular solution of plane harmonic function, the problem of Saint_Venant bending of a cracked cylinder by a transverse force was reduced to solving two sets of integral equations and its general solution was then obtained. Based on the obtained solution, a method to calculate the bending center and the stress intensity factors of the cracked cylinger whose cross_section is not thin_walled, but of small torsion rigidity is proposed. Some numerical examples are given.
基金Project(51105287) supported by the National Natural Science Foundation of ChinaProject(2012BAA08003) supported by the Key Research and Development Project of New Products and New Technologies of Hubei Province, ChinaProject(2011-P05) supported by the State Key Laboratory of Materials Processing and Die & Mould Technology, Huazhong University of Science and Technology,China
文摘The aim of this work is to propose a 3D FE model of a theoretical assembling straight bevel gear pair to analyze the contact fatigue on the tooth surface and the bending fatigue in the tooth root. Based on the cumulative fatigue criterion and the stress-life equation, the key meshing states of the gear pair were investigated for the contact fatigue and the bending fatigue. Then, the reliability of the proposed model was proved by comparing the calculation result with the simulation result. Further study was performed to analyze the variation of the contact fatigue stress and the bending fatigue stress under different loads. Furthermore, the roles of the driving pinion and the driven gear pair were evaluated in the fatigue life of the straight bevel gear pair and the main fatigue failure mode was determined for the significant gear. The results show that the fatigue failure of the driving pinion is the main fatigue failure for the straight bevel gear pair and the bending fatigue failure is the main fatigue failure for the driving pinion.
基金Project(20050216013) supported by the Research Fund for the Doctoral Program of Higher Education
文摘Accurate springback prediction of wide sheet metal air bending process is important to improve product quality and ensure the precision in dimension. The definition of elastic limit bend angle was proposed. Based on cantilever beam elastic deforming theory, the geometrical parameters of forming tools, sheet thickness and the material yielding strain were derived and validated by the finite element method (FEM). Employing the degree of elastic limit bend angle, the equation for springback prediction was constructed, the results calculated fit well with experimental data. Especially for the small bend angle, the predicted results by equation were applied to conduct the springback prediction and compensation in industries and give closer correlation to the experimental data than those calculated by engineering theory of plastic bending.
