Study on Mathematical interpolation and correction of three - dimensional modeling of high - speed railway

Author(s):  
Jun Gao ◽  
Xiao Lin
Author(s):  
M.A. Baburin ◽  
V.D. Baskakov ◽  
S.V. Eliseev ◽  
K.A. Karnaukhov ◽  
V.A. Tarasov

Experimental and analytical research methods of losses of stability of meniscal form liners at their high-speed deformation, i.e., collapse, by products of detonation of explosive have limited opportunities. They are caused by the complicated nature of liner thickness change to control the operated loss of stability --- folding, high-speed deformations of liners, intensive drop of pressure acting on them and some other features. The paper introduces an approach to numerical three-dimensional modeling of collapse of meniscal form liners with variable thickness in the circumferential direction in the area of their periphery, the modeling being carried out by the finite element method in Lagrange coordinate system in LS-DYNA software package. The study also shows the main stages of implementing this approach and describes the key parameters of the materials models used, as well as the type of the final element and mechanism of adaptive updating of the computational grid. By the method of numerical simulation, we found the main regularities of liners collapse and folding of the afterbody of high speed elements formed during the collapse of the liners. The results of numerical calculations are confirmed by experimental data. The studies done are of interest to specialists involved in the analysis of the loss of stability of various structures under dynamic loads, as well as to specialists in the field of explosion and impact physics.


2013 ◽  
Vol 631-632 ◽  
pp. 1068-1072
Author(s):  
Yan Wu ◽  
Yan Ma

When the intermediate cuttings cut the wood, the efficiency of the vibration of the circular saw web was low so that the saw web always broke off. Moreover, the high-speed rotation would cause the vibration of the complete machine and result in the initial failure of the machine. Therefore, seeing from the problems from the analysis above and practice, the new design of the current micro intermediate cuttings seemed especially important. In the thesis, the author made a new arrangement of the micro intermediate cuttings of machinery tools, carrying out three-dimensional modeling and simulation of the complete machine and made an analysis of the dynamic cutting process by means of analyzing the working condition of circular saw web.


2014 ◽  
Vol 137 (1) ◽  
Author(s):  
Ophélie Chevalier ◽  
André Langlet ◽  
Laetitia Fouché-Sanseigne ◽  
Yann Guilmard

The aim of this work is to assess the influence of the dynamic stresses (due to the projectile displacement and the gas pressure) on the lifetime of certain medium caliber (less than 40 mm) gun barrels. First, an experimental study of tube dynamics under high speed loads was made. The large number of experimental measurements made it possible for us to identify the forcing effect of the projectile. In parallel, experimental samples were submitted to periodic traction-compression forces in order to obtain the material parameters of the barrels used in the study. Second, a finite element (FE) model was elaborated which faithfully forecasts the experimental strain records. Three-dimensional modeling permitted us to correctly evaluate the response in the zones of stress concentration. Third, a lifetime calculation was performed. This shows that the lifetime of the barrel is determined by the most constrained zones during firing: in the present case by the stresses appearing at the bottom of the grooves.


Sign in / Sign up

Export Citation Format

Share Document