The Effect of Viscous and Hysteretic Damping on Rotor Stability

2000 ◽  
Author(s):  
Anthony M. Cerminaro ◽  
Frederick C. Nelson
Keyword(s):  
Finite Element ◽  
Numerical Study ◽  
Rotor System ◽  
Viscous Damping ◽  
Finite Element Program ◽  
Hysteretic Damping ◽  
Element Program

A rotordynamic finite element program has been modified to include internal viscous and hysteretic damping. A numerical study has been done on a rotor system with variable external damping to predict the effect of various amounts of internal viscous and hysteretic damping on rotor stability. Three cases are considered: (1) external viscous damping with internal viscous damping; (2) external hysteretic damping with internal hysteretic damping; and (3) external viscous damping with internal hysteretic damping.

An Experimental and Numerical Study to Analysis and Design of Sheet Hydroforming Process for an Automobile Fender Shell

2006 ◽  
Author(s):  
Mohammad Habibi Parsa ◽  
Payam Darbandi
Keyword(s):  
Finite Element ◽  
Numerical Study ◽  
Fluid Pressure ◽  
Finite Element Program ◽  
New Approach ◽  
Explicit Finite Element ◽  
Sheet Hydroforming ◽  
Analysis And Design ◽  
Hydroforming Process ◽  
Element Program

A new approach for manufacturing of shell fender is proposed and has been examined numerically and experimentally. The new suggested method is based on sheet hydroforming process, which has a lot of advantages over conventional deep drawing process. After defining the shape of initial blank using an inverse finite element program, numerical evaluation of the proposed sheet hydroforming process for production of shell fender has been carried out using an explicit finite element code considering fluid pressure, boundary conditions and tools. Then experimental evaluation has been carried out using down sized specimen and the results have been compared with results of previous simulations. It has been shown that there are similar trends between finite element and experimental results.

Nonlinear Numerical Study of Cold-Formed Lipped Channel Beam-Columns

2014 ◽  
Vol 919-921 ◽  
pp. 183-187
Author(s):  
Ming Chen ◽  
Zhi Bin Feng ◽  
Zhou Zhou ◽  
Ya Long Wang ◽  
Qiang Zhang
Keyword(s):  
Finite Element ◽  
Numerical Study ◽  
Engineering Practice ◽  
Time Saving ◽  
Finite Element Program ◽  
Beam Columns ◽  
Load Carrying ◽  
Element Program ◽  
Channel Beam ◽  
Overall Buckling

Cold-formed lipped channel sections may fail in local, distortional and overall buckling under compression. With the development of computer technology, finite element analyses of these sections play increasing important roles in engineering practice for economic design and time-saving purpose. A kind of typical cold-formed lipped channel beam-column with varying load eccentricity was analyzed in this paper by using the finite element program of ANSYS to observe the buckling modes and load carrying capacities of the columns. All the results can be the reference for further studies.

Computational Technique of the Sliding Interface in Numerical Simulations of 3D Penetration

2013 ◽  
Vol 477-478 ◽  
pp. 295-298
Author(s):  
Jun Yan ◽  
Feng Wang ◽  
Jian Hua Shen ◽  
Lin Sha
Keyword(s):  
Finite Element ◽  
Numerical Study ◽  
Computational Technique ◽  
Analog Computation ◽  
Finite Element Program ◽  
3D Finite Element ◽  
Aluminum Target ◽  
Sliding Interface ◽  
Element Program ◽  
Lagrange Finite Element

Based on the Lagrange finite element method, a simplified computational technique for sliding interface in oblique penetration is proposed in the paper. By applying the 3D finite element program developed on this technique to numerical analog computation of ogive-noded steel rod penetrating in the aluminum target, a result which is consistent with that of A.J.Piekutowskis experiment can be reached. Hence it proves the rationality and validity of the program and method discussed in this paper and that the method is useful in the numerical study of penetration and perforation.

scholarly journals The impact of drilling and slitting construction on damage field: evolution characteristics in low-permeability coal seam

2021 ◽  
Vol 37 ◽  
pp. 205-215
Author(s):  
Heng Chen ◽  
Hongmei Cheng ◽  
Aibin Xu ◽  
Yi Xue ◽  
Weihong Peng
Keyword(s):  
Finite Element ◽  
Rock Mass ◽  
Damage Mechanics ◽  
Effective Strain ◽  
Secondary Development ◽  
Distribution Area ◽  
Finite Element Program ◽  
Element Program ◽  
Mining Face ◽  
The Impact

ABSTRACT The fracture field of coal and rock mass is the main channel for gas migration and accumulation. Exploring the evolution law of fracture field of coal and rock mass under the condition of drilling and slitting construction has important theoretical significance for guiding efficient gas drainage. The generation and evolution process of coal and rock fissures is also the development and accumulation process of its damage. Therefore, based on damage mechanics and finite element theory, the mathematical model is established. The damage variable of coal mass is defined by effective strain, the elastoplastic damage constitutive equation is established and the secondary development of finite element program is completed by FORTRAN language. Using this program, the numerical simulation of drilling and slitting construction of the 15-14120 mining face of Pingdingshan No. 8 Mine is carried out, and the effects of different single borehole diameters, different kerf widths and different kerf heights on the distribution area of surrounding coal fracture field and the degree of damage are studied quantitatively. These provide a theoretical basis for the reasonable determination of the slitting and drilling arrangement parameters at the engineering site.

Finite Element Analysis on the Deformation of Energy-Saving Wire-Mesh Frame Wallboard

2014 ◽  
Vol 501-504 ◽  
pp. 731-735
Author(s):  
Li Zhang ◽  
Kang Li
Keyword(s):  
Finite Element ◽  
Energy Saving ◽  
Theoretical Basis ◽  
Steel Wire ◽  
Wire Mesh ◽  
Design Parameters ◽  
Element Analysis ◽  
Finite Element Program ◽  
Element Program ◽  
Influence Degree

This paper analyzes the influence degree of related design parameters of wire-mesh frame wallboard on deformation through finite element program, providing theoretical basis for the design and test of steel wire rack energy-saving wallboard.

scholarly journals Numerical Analyses of Earthquake Induced Liquefaction and Deformation Behaviour of an Upstream Tailings Dam

2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Muhammad Auchar Zardari ◽  
Hans Mattsson ◽  
Sven Knutsson ◽  
Muhammad Shehzad Khalid ◽  
Maria V. S. Ask ◽  
...  
Keyword(s):  
Finite Element ◽  
Seismic Event ◽  
Deformation Behaviour ◽  
Ground Surface ◽  
Tailings Dam ◽  
Limited Extent ◽  
Northern Sweden ◽  
Finite Element Program ◽  
Dynamic Analyses ◽  
Element Program

Much of the seismic activity of northern Sweden consists of micro-earthquakes occurring near postglacial faults. However, larger magnitude earthquakes do occur in Sweden, and earthquake statistics indicate that a magnitude 5 event is likely to occur once every century. This paper presents dynamic analyses of the effects of larger earthquakes on an upstream tailings dam at the Aitik copper mine in northern Sweden. The analyses were performed to evaluate the potential for liquefaction and to assess stability of the dam under two specific earthquakes: a commonly occurring magnitude 3.6 event and a more extreme earthquake of magnitude 5.8. The dynamic analyses were carried out with the finite element program PLAXIS using a recently implemented constitutive model called UBCSAND. The results indicate that the magnitude 5.8 earthquake would likely induce liquefaction in a limited zone located below the ground surface near the embankment dikes. It is interpreted that stability of the dam may not be affected due to the limited extent of the liquefied zone. Both types of earthquakes are predicted to induce tolerable magnitudes of displacements. The results of the postseismic slope stability analysis, performed for a state after a seismic event, suggest that the dam is stable during both the earthquakes.

A preprocessor for the finite element program SAP IV

1981 ◽  
Vol 17 (12) ◽  
pp. 1779-1789
Author(s):  
E. Haugeneder ◽  
W. Prochazka ◽  
P. Tavolato
Keyword(s):  
Finite Element ◽  
Finite Element Program ◽  
Element Program
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