Mechanical Properties of Uranium Silicides by Nanoindentation and Finite Elements Modeling

These last years, hemp fibres are using as reinforcement for compounds based on polymer in different industrial manufacturing for their interesting mechanical and ecological properties. The hemp fibres present a non constant cross section and complex geometry that can have a high effect on their mechanical properties. The mechanical properties of hemp fibres (Young moduli, longitudinal stress and failure strain) are rather difficult and request a specific characterization method. In this study, a micro-traction test coupled with a numerical imaging treatment and a finite elements method are used. The mechanical tensile test allows to determinate the evolution of the traction load in function of the displacement until the fibre crack. The numerical imaging allows to measure finely the hemp cross section along the fibre and aims to reconstruct a 3D hemp fibre object model from an image sequence captured by a mobile camera. And lastly, the finite elements method allows to take the real fibre geometry into consideration for the mechanical characterization using inverse optimization simplex method.

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Finite Elements Modeling and Analysis of Cold-Formed Steel Frame Shear Walls

International Journal of Engineering and Technology ◽

10.7763/ijet.2012.v4.471 ◽

2012 ◽

Vol 4 (6) ◽

pp. 719-722

Author(s):

Mahdi Bitarafan ◽

Youssef Hussein- Zadeh ◽

Farzad Pichkah ◽

Shahin Lale Arefi

Keyword(s):

Finite Elements ◽

Shear Walls ◽

Steel Frame ◽

Modeling And Analysis ◽

Finite Elements Modeling ◽

Cold Formed Steel

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TN X SN Fatigue Curves for KS Hook and Chain Using Finite Elements Modelling and Model Test

Volume 4: Materials Technology; Ocean Engineering ◽

10.1115/omae2007-29051 ◽

2007 ◽

Author(s):

Jose´ Carlos Lima de Almeida ◽

Ronaldo Rosa Rossi ◽

Ricardo Sobral

Keyword(s):

Finite Elements ◽

Model Test ◽

Fatigue Curve ◽

Functional Condition ◽

Mooring Line ◽

Hardness Profile ◽

Mooring Lines ◽

Finite Elements Modeling ◽

Predicting Behavior ◽

Finite Elements Modelling

The new scenario of oil exploration in ultra deep water moves forward to 3000 m, has been putting for the companies that accept this technological challenger significant, border of the techno-scientific knowledge. Therefore, nowadays in this case of ultra deep waters, where the forces above the mooring lines are increase and the use of the new material in Petrobras Floating Production Units, it is necessary the good numerical analyses and experimental test by the mooring line. It appears the need to look for a solution for the problems according to the changes of the polyester rope in the production platform without the bottom extension change and its foundation (fixed point). According to this challenge it was necessary to develop a remote connection and disconnection device. This device is the KS hook and its optimization has been created using the fracture mechanical conception optics and computers tools (FEM and mooring software). There are two conditions to develop this device: one condition is functional and the other is structural. For the functional condition, it’s necessary to create the facilities for handling and installations. For the structural conditions, it is necessary to use the special wrought steel material, treatment for steel characteristic and right geometry. Finite Elements Modeling analyze used the Ansys software, considered the hardness profile material for Minimum Break Load (MBL). The lifetime design is about 25 years for this case and the fatigue analysis considered the residual stress and plasticity for structural device. Previous simulation is especially important in predicting behavior and in the development of new design products before testing. The model was meshed with 3D first order tetrahedral elements solid45. The mesh was sufficiently fine to ensure minimal loss of accuracy in curved geometry. There isn’t a TN fatigue curve (reference API Fatigue curves) for this KS Hook device geometry, in this case become necessary to use the model test to obtain this curve with the extrapolation of the results. The Finite Elements Modeling analyze used with the Material SN Fatigue curve will be used for this validation. Previous simulation is especially important in predicting behavior and in the development of new design products before testing.

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Finite elements modeling of multilayers of Cr/CrN

Microelectronics Journal ◽

10.1016/j.mejo.2008.01.078 ◽

2008 ◽

Vol 39 (11) ◽

pp. 1336-1338 ◽

Cited By ~ 6

Author(s):

S. Amaya-Roncancio ◽

E. Restrepo-Parra

Keyword(s):

Finite Elements ◽

Finite Elements Modeling

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Efficiency Assessment of the Composite Materials Repair Systems Intended for Corrosion Damaged Pipelines

Volume 8: Polar and Arctic Sciences and Technology; Petroleum Technology ◽

10.1115/omae2019-96279 ◽

2019 ◽

Author(s):

Andrei Dumitrescu ◽

Alin Diniţă

Keyword(s):

Mechanical Properties ◽

Composite Material ◽

Finite Elements ◽

Numerical Models ◽

Plastic Region ◽

Research Work ◽

Repair System ◽

Composite Repair ◽

Erosion Processes ◽

Repair Systems

Abstract This paper presents the results of the research work carried out by the authors in order to evaluate the efficiency of the composite material wraps/sleeves (made of a polymeric matrix and reinforcing fabric) used to repair steel pipelines carrying hydrocarbons upon which local metal loss defects (generated by corrosion and/or erosion processes) have been detected. The pipeline repair technologies consisting of the application of composite material wraps are perceived as being advantageous alternative solutions for substituting the conventional technologies, which require welding operations to be performed in the pipe areas with defects. The efficiency of the composite repair systems has been investigated by assessing the reinforcement effects (the restoration level of the damaged pipe mechanical strength) generated by the applied composite wraps as a function of their geometry and mechanical properties. To that purpose, numerical models based on finite elements have been developed and certified by comparing them with the results of several experimental programs previously performed by the authors. Finite elements simulations have also been conducted in the plastic region, taking into account material non-linearity. The calculation methods proposed in literature (among which a method previously developed by the authors) to define the composite wrap dimensions (thickness and length) for a given pipe have also been investigated and compared to our numerical results in order to select the most adequate solution for the design of the composite repair system. The optimal values for the mechanical properties of the composite material used by the repair system have also been defined.

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