Residual Stress Finite Element Analysis and Measurements of a Tube Penetration J-Groove Attachment Weld in a Hemispherical Head of a Large Ferritic Pressure Vessel: Part II — Outer Nozzle

2006 ◽  
Author(s):  
R. Dennis ◽  
N. Leggatt ◽  
C. T. Watson ◽  
E. Kingston ◽  
D. J. Smith
Keyword(s):  
Residual Stress ◽  
Finite Element Analysis ◽  
Finite Element ◽  
Finite Element Model ◽  
Pressure Vessel ◽  
Element Model ◽  
Hole Drilling ◽  
Poor Correlation ◽  
Element Analysis ◽  
The Finite Element Model

A programme of work was undertaken to gain an understanding of the residual stress levels in the tube penetration J-groove welds in a hemispherical head of a large stainless steel clad ferritic pressure vessel. This second part of a two-part paper describes the finite element analysis that was carried out to model an off-centre outer tube to vessel head weld. A 3D finite element residual stress model was developed. The complex bead deposition sequence of the actual weld was simulated by a bead lumping approach using 9 passes. The results from the finite element analyses were compared with both surface and through thickness stress measurements. These measurements were taken on a mock weld that was representative of the actual component. The surface measurements were taken by using an incremental centre hole drilling technique. The through thickness values were obtained from deep hole drilling measurements at three positions around the circumference of the weld. For this off-centre penetration the cladding process was not modelled nor was clad applied to the test mock-up. The finite element results and the measured values showed similar trends in the variation of stress around the circumference of the weld. A poor correlation between measurements and analytical results was obtained at the lower hillside position. A major reason for the discrepancy is believed to be that the bead lumping approach that was used in the finite element model was not a sufficiently refined representation of the actual weld bead deposition sequence. Note however that one of the aims of this finite element analysis was to quantify the variations between the centre tube presented in the first part of this paper and the off centre tube presented here. In this regard the finite element model and measurements compared well. The finite element model was also used to carry out two sensitivity studies that investigated the effects upon residual stress of tube geometry and material properties. For the case where a nozzle tube was extended significantly below the vessel head inner surface the results showed the stresses to be significantly higher than the baseline case.

Finite Element Analysis of Structural Strength of Concrete Mixing Truck’s Frame

2014 ◽  
Vol 945-949 ◽  
pp. 1143-1149
Author(s):  
Hai Xia Sun ◽  
Hua Kai Wei ◽  
Xiao Fang Zhao ◽  
Jia Rui Qi
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Finite Element Model ◽  
Structural Strength ◽  
Element Model ◽  
Basic Element ◽  
Operating Conditions ◽  
Frame Structure ◽  
Element Analysis ◽  
The Finite Element Model

The finite element model of the concrete mixing truck’s frame is builded by using shell as basic element, and the process of building the finite element model of the balance suspension is introduced in detail. Based on this, frame’s stress on five types of typical operating conditions are calculated by using the finite element analysis software, NASTRAN, and results can show the dangerous position and the maximum stress position on the frame. The analysis result on structural strength can provide the basis for further improving the frame structure.

Theoretical and Finite Element Analysis of Crosshead of Quintuple Cylinders Fracturing Pump

2011 ◽  
Vol 201-203 ◽  
pp. 253-256 ◽  
Author(s):  
Zhi Peng Lv ◽  
Si Zhu Zhou ◽  
Xiu Hua Ma
Keyword(s):  
Boundary Condition ◽  
Finite Element Analysis ◽  
Finite Element ◽  
Finite Element Model ◽  
Element Model ◽  
Maximum Force ◽  
Element Analysis ◽  
Plunger Pump ◽  
Load Handling ◽  
The Finite Element Model

According to the plunger pump movement principle, this paper analyzed the two kind of typical force situation of the crosshead, and obtained the theoretical maximum force. Established the finite element model of the crosshead, gave an analysis to the load handling and boundary condition. The last results of the node stress and displacement show that the crosshead can work safely.

Finite-Element Analysis of 10kN Deadweight Force Standard Machine Reverse Frame

2013 ◽  
Vol 694-697 ◽  
pp. 194-197
Author(s):  
Li Juan Yu ◽  
Chang Ju Xu ◽  
Xue Cheng Zhang
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Finite Element Model ◽  
Critical Condition ◽  
Element Model ◽  
Element Analysis ◽  
Model Stability ◽  
Pulling Force ◽  
The Finite Element Model

In the test enginery, using reverse frame put the pulling force into the pressure is the most commonly structure method. This paper analyzed the buckling problem of the process of reverse frame working, established the finite element model , stability analyzed , putted forward and proved the critical condition of reverse frame in the course of stability, Verified in 10kN deadweight force standard machine.

A Finite Element Analysis for Unbonded Flexible Risers Under Torsion

2007 ◽  
Author(s):  
A. Bahtui ◽  
H. Bahai ◽  
G. Alfano
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Numerical Model ◽  
Finite Element Model ◽  
Time Integration ◽  
Element Model ◽  
Integration Scheme ◽  
Element Analysis ◽  
Benchmark Solutions ◽  
The Finite Element Model

This paper presents a detailed finite element analysis of a five-layer unbonded flexible riser. The numerical results are compared analytical solutions for various load cases. In the finite element model all layers are modelled separately with contact interfaces placed between each layer. The finite element model includes the main features of the riser geometry with very little simplifying assumptions made. The numerical model was solved using a fully explicit time-integration scheme implemented in a parallel environment on a 16-processor cluster. The very good agreement found from numerical and analytical comparisons validates the use of our numerical model to provide benchmark solutions against which further detailed investigation will be made.

Effects of Air Bending Parameters on Spingback Using Finite Element Analysis

2013 ◽  
Vol 423-426 ◽  
pp. 978-983
Author(s):  
Xie Li
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Finite Element Model ◽  
Element Model ◽  
Internal Stresses ◽  
Element Analysis ◽  
Air Bending ◽  
Bending Process ◽  
Punch Radius ◽  
The Finite Element Model

Springback is a common phenomenon in air bending of sheet metal forming, caused by the elastic redistribution of the internal stresses during unloading. It has been recognized that springback is essential for the design of the air bending. Traditionally, the values of springback is obtained for air bending parameters from handbook tables or springback graphs. However, the handbook tables or springback graphs are obtained using experiments and it is a time consuming processes. In this paper, a finite element model has been used to analyze the air bending process. Some experiments are carried out on ST12 materials, and the finite element model is validated comparing with experiments. In the present research the influence of process variables such as punch radius, die radius and die on springback are discussed using finite element analysis. Thus, the presented results of this research provide a basis of design to improve forming quality.

Finite Element Analysis of Head-Form Impacting Laminated Glass for Automotive Windscreens

2016 ◽  
Vol 680 ◽  
pp. 72-75
Author(s):  
Yan Min ◽  
Zeng Chen Cao ◽  
Shuang Li
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Finite Element Model ◽  
Mechanical Behavior ◽  
Element Model ◽  
Laminated Glass ◽  
Element Analysis ◽  
Head Form ◽  
Set Up ◽  
The Finite Element Model

Based on GB/T 5137.1-2002 experiment specification, the finite element model of head-form impacting laminated glass for automotive windscreens is set up in this paper. According to Finite Element Analysis results of laminated glass with different structure and further analyzing impact property and mechanism of laminated glass , the influence rule of the structure of the laminated glass on the mechanical behavior is discussed. (H)

Finite Element Analysis of Air Transportation Load-Unload Platform’s Frame Using ANSYS

2014 ◽  
Vol 644-650 ◽  
pp. 659-662
Author(s):  
Hong An ◽  
Kun Wang ◽  
Chen Guang Liang ◽  
Yu Rui Guo
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Finite Element Model ◽  
Element Model ◽  
Air Transportation ◽  
Static Characteristics ◽  
Element Analysis ◽  
Design Scheme ◽  
The Finite Element Model

Create 3D entity model of the loader’s frame in Solidworks, assemble the frame and then import in ANSYS to get the finite element model of the frame, and use ANSYS to analysis the frame at 5 Static characteristics of different conditions. The analysis indicates that the design scheme of the frame is feasible, but need to increase the stiffness of the structure in some parts.

Finite Element Analysis on Large-Scale Electrical Dust Precipitator Steel Structures

2013 ◽  
Vol 753-755 ◽  
pp. 1196-1200
Author(s):  
Lu Yu Huang ◽  
Yang Gao ◽  
Xia Cao
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Finite Element Model ◽  
Optimization Design ◽  
Large Scale ◽  
Steel Structures ◽  
Element Model ◽  
Element Analysis ◽  
Dust Precipitator ◽  
The Finite Element Model

Based on the construction features of the steel structures of a type of electrical dust precipitator, a finite element model is established with large-scale finite element analysis software ANSYS, and the structure stress and displacement of the model under all sorts of loads are analyzed with the frontal solution method. The results indicate that analysis is relatively accurate, the finite element model and the analysis method is appropriate. The result can be further used for optimization design of the electrical precipitator steel structures.

Dependence of Elastic Properties of Human Femoral Cortical Bone on Porosity

2015 ◽  
Author(s):  
Maryam Khosroshahi ◽  
Fred Barez ◽  
Amer El-Hage ◽  
James Kao
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Finite Element Model ◽  
Cortical Bone ◽  
Elastic Properties ◽  
Transversely Isotropic ◽  
Element Model ◽  
Element Analysis ◽  
Age Related ◽  
The Finite Element Model

Hip fracture is one of the most serious and common health problems among elderly which may lead to permanent disability or death. Hip fracture commonly occurs in the femoral bone, the major bone in the hip joint. Microscopic age-related changes in the structure of cortical bone is one of the factors that is considered to be partially responsible for the increase of fracture risk in elderly. It is of great interest to develop a predictable model of such fractures for the aging population in preparation of a suitable therapy. These micro structural changes influence mechanical properties and, therefore, behavior of bone and are critical to understand risk and mechanics of fracture of bone. Correlation between cortical bone strength and porosity, as a microscopic structural factor, has been examined frequently as a function of age and/or porosity. These studies have investigated the effect of porosity experimentally and have not studied the effect of porosity independently from other structural factors such as bone mineral density. In this study effect of porosity on elastic properties of human femoral cortical bone was studied independently using finite element analysis assuming transversely isotropic behavior in terms of elastic properties with the axis of elastic properties along the longitudinal axis of femur shaft. In this study, published standard mechanical tests for transversely isotropic materials were simulated using finite element computer simulation on models with different porosities. The developed finite element model utilized material properties based on the best fit regression in previously published articles. Pores’ size, shape and distribution were also modeled based on previous experimental studies. The finite element model, in general, predicted behavior of five independent elastic mechanical properties, namely, longitudinal Young’s modulus, transverse poisson’s ratio, transverse shear modulus, transverse Young’s modulus and longitudinal poisson’s ratio, as a function of porosity. Furthermore, effect of porosity on the elastic properties across various age groups was investigated using published data on age-related changes in bone porosity. Mathematical models based on Finite Element Analysis results have been developed using linear least square regression. These models show negative linear relationship between studied elastic properties of human femoral cortical bone and porosity. The Finite Element Analysis results compared well with the previously published experimental data. Furthermore, the results obtained show the elastic properties as functions of age for females and males. The predicted values for elastic properties are lower for men compared to women of age 20 to 40 years old. However, after the age of 44, elastic properties of femoral cortical bone for men are higher than women. The Finite Element Model developed in this study will help to create a clinical bone model for the prediction of fracture risk or the selection of suitable therapy in orthopedic surgery.

Densification Behaviour Modelling for Metallic Powders

2014 ◽  
Vol 802 ◽  
pp. 317-322 ◽  
Author(s):  
Maria Carolina dos Santos Freitas ◽  
José Adilson de Castro ◽  
Luciano Pessanha Moreira ◽  
Flávia de Paula Vitoretti
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Finite Element Model ◽  
Element Model ◽  
Porous Metals ◽  
Explicit Integration ◽  
Element Analysis ◽  
Conventional Press ◽  
Powder Forming ◽  
The Finite Element Model

Powder forming involves fabrication of a preform by conventional press-and-sinter processing, followed by various forming processes, citing as examples, rolling, compaction, forging, extrusion, among others, of the porous preform into a final shape through substantial densification. This work makes a finite element analysis for porous metals. The finite element model was applied to simulating the case of compaction of nanocristalline copper under uniaxial compression conditions in order investigate the densification behavior. The model was simulated using explicit integration method as applied to the evolution variation of the relative density and the dislocation density of the compact. Finite element analysis program used was Abaqus. Finite element calculations were compared with literature data. The agreements between finite element model and literature results for densification of nanocristalline copper were good.

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