The 19^(th) National Congress of the Communist Party of China(CPC)established Xi Jinping Thought on Socialism with Chinese Characteristics for a New Era as the guiding ideology of the CPC,marking a new leap forward in...The 19^(th) National Congress of the Communist Party of China(CPC)established Xi Jinping Thought on Socialism with Chinese Characteristics for a New Era as the guiding ideology of the CPC,marking a new leap forward in synthesizing basic principles of Marxism with China’s concrete conditions.This Thought enriches and develops scientific socialism,the guiding ideology of the International展开更多
Eringen’s two-phase local/nonlocal model is applied to an Euler-Bernoulli nanobeam considering the bending-induced axial force, where the contribution of the axial force to bending moment is calculated on the deforme...Eringen’s two-phase local/nonlocal model is applied to an Euler-Bernoulli nanobeam considering the bending-induced axial force, where the contribution of the axial force to bending moment is calculated on the deformed state. Basic equations for the corresponding one-dimensional beam problem are obtained by degenerating from the three-dimensional nonlocal elastic equations. Semi-analytic solutions are then presented for a clamped-clamped beam subject to a concentrated force and a uniformly distributed load, respectively. Except for the traditional essential boundary conditions and those required to be satisfied by transferring an integral equation to its equivalent differential form, additional boundary conditions are needed and should be chosen with great caution, since numerical results reveal that non-unique solutions might exist for a nonlinear problem if inappropriate boundary conditions are used. The validity of the solutions is examined by plotting both sides of the original integro-differential governing equation of deflection and studying the error between both sides. Besides, an increase in the internal characteristic length would cause an increase in the deflection and axial force of the beam.展开更多
The objective of this paper is mainly to investigate the ventilated tail cavity flow of an underwater vehicle with focus on the gas leakage regime by experimental and numerical methods.A high-speed camera and pressure...The objective of this paper is mainly to investigate the ventilated tail cavity flow of an underwater vehicle with focus on the gas leakage regime by experimental and numerical methods.A high-speed camera and pressure measurement system are used to record the cavity flow patterns and pressure behavior,respectively.The numerical simulation is carried out with volume of fluid(VOF)model and Filter-based turbulence model(FBM).Good agreement can be obtained between the experimental and numerical results.There are three gas leakage types in the evolution of the intact tail cavity,i.e.,twin-vortex tube entrainment(TVTE),toroidal vortex shedding(TVS)and hybrid twin-vortex tube entrainment and toroidal vortex shedding(TVTE-TVS).With the increase of Fr,the unsteady behavior of the cavity with different gas leakage types becomes more apparent.The internal flow characteristics revealed three distinct regions including the ventilation influence region,the reverse flow region and the high shear flow region and have an important effect on the transition of gas leakage regime.展开更多
文摘The 19^(th) National Congress of the Communist Party of China(CPC)established Xi Jinping Thought on Socialism with Chinese Characteristics for a New Era as the guiding ideology of the CPC,marking a new leap forward in synthesizing basic principles of Marxism with China’s concrete conditions.This Thought enriches and develops scientific socialism,the guiding ideology of the International
基金Project supported by the National Natural Science Foundation of China(No.11472130)
文摘Eringen’s two-phase local/nonlocal model is applied to an Euler-Bernoulli nanobeam considering the bending-induced axial force, where the contribution of the axial force to bending moment is calculated on the deformed state. Basic equations for the corresponding one-dimensional beam problem are obtained by degenerating from the three-dimensional nonlocal elastic equations. Semi-analytic solutions are then presented for a clamped-clamped beam subject to a concentrated force and a uniformly distributed load, respectively. Except for the traditional essential boundary conditions and those required to be satisfied by transferring an integral equation to its equivalent differential form, additional boundary conditions are needed and should be chosen with great caution, since numerical results reveal that non-unique solutions might exist for a nonlinear problem if inappropriate boundary conditions are used. The validity of the solutions is examined by plotting both sides of the original integro-differential governing equation of deflection and studying the error between both sides. Besides, an increase in the internal characteristic length would cause an increase in the deflection and axial force of the beam.
基金supported by the National Natural Science Foundation of China(Grant No.U20B2005).
文摘The objective of this paper is mainly to investigate the ventilated tail cavity flow of an underwater vehicle with focus on the gas leakage regime by experimental and numerical methods.A high-speed camera and pressure measurement system are used to record the cavity flow patterns and pressure behavior,respectively.The numerical simulation is carried out with volume of fluid(VOF)model and Filter-based turbulence model(FBM).Good agreement can be obtained between the experimental and numerical results.There are three gas leakage types in the evolution of the intact tail cavity,i.e.,twin-vortex tube entrainment(TVTE),toroidal vortex shedding(TVS)and hybrid twin-vortex tube entrainment and toroidal vortex shedding(TVTE-TVS).With the increase of Fr,the unsteady behavior of the cavity with different gas leakage types becomes more apparent.The internal flow characteristics revealed three distinct regions including the ventilation influence region,the reverse flow region and the high shear flow region and have an important effect on the transition of gas leakage regime.
