Influence of layers on flexural motion of a multilayer assembly due to the laser ablation process

2003 ◽  
Vol 217 (8) ◽  
pp. 945-954 ◽  
Author(s):  
B S Yilbas ◽  
J Hyder
Keyword(s):  
Equivalent Stress ◽  
Substrate Material ◽  
Liquid Interface ◽  
Flexural Wave ◽  
Maximum Magnitude ◽  
Pressure Loading ◽  
Maximum Displacement ◽  
Recoil Pressure ◽  
Laser Ablation Process ◽  
Maximum Equivalent Stress

Laser-induced evaporation results in recoil pressure at the vapour-liquid interface, which in turn gives rise to flexural wave generation in the substrate material due to impact pressure loading at the interface. In the present study, recoil pressure due to laser non-conduction limited heating is formulated and because of pressure loading at the vapour-liquid interface the flexural motion of the substrate material is modelled. A multilayer cantilever arrangement of the workpiece, consisting of layers of steel and Inconel alloy, is considered. In order to investigate the influence of the number of layers on the resulting flexural motion and stress fields, four cases and three layer arrangements are taken into account. It is found that the maximum displacement in the order of 10-4m occurs while the maximum equivalent stress is about 20 MPa. The maximum magnitude of shear stress is higher than that of equivalent stress.

Design, Modeling and Finite Element Static Analysis of a New Two Axis Solar Tracker Using SolidWorks/COSMOSWorks

2013 ◽  
Vol 446-447 ◽  
pp. 738-743 ◽  
Author(s):  
Fateh Ferroudji ◽  
Toufik Ouattas ◽  
Chérif Khélifi
Keyword(s):  
Finite Element ◽  
Static Analysis ◽  
Safety Factor ◽  
Equivalent Stress ◽  
Maximum Displacement ◽  
3D Cad ◽  
Optimum Position ◽  
Maximum Equivalent Stress ◽  
Solar Tracker ◽  
The Stability

This paper presents the now design, modeling and static analysis of a new two-axis solar tracker (Azimuth and Altitude). The tracker is an electro-hydraulic device that keeps photovoltaic panels in an optimum position perpendicularly to the solar radiation during daylight hours. The tracker of 24 m² panel’s size was designed using the SolidWorks 3D CAD software. The finite element method (FEM) is adopted to ensure the stability and the reliability of the tracker. COSMOSWorks was used to determine displacement, equivalent stress and safety factor of the tracker under its own weight and wind load critical, namely wind speed of 130 km/h. Simulation results show that the maximum displacement of the structure is 1.18 mm, the level of the maximum equivalent stress is 74.43 MPa and the safety factor is about 3. The tracker structure completely satisfies the design requirements.

Flexural motion due to laser ablation: Influence of force location on the flexural motion

2004 ◽  
Vol 218 (12) ◽  
pp. 1411-1420 ◽  
Author(s):  
B S Yilbas ◽  
J Hyder
Keyword(s):  
Shear Stress ◽  
Laser Ablation ◽  
Maximum Shear Stress ◽  
Substrate Material ◽  
Thin Layers ◽  
Stress Fields ◽  
Pressure Force ◽  
Ablation Process ◽  
Maximum Displacement ◽  
Recoil Pressure

The flexural motion of a multilayer assembly subjected to laser ablation is studied. The assembly consists of thin layers of Inconel alloy (top and bottom layers) and a steel layer (intermediate layer). The assembly resembles a stainless steel sheet with both surfaces coated. The recoil pressure generated during the ablation process results in a loading pressure force acting normal to the assembly surface. The pressure force causes flexural motion in the assembly. In order to secure a sufficiently large flexural displacement, a cantilever arrangement of the assembly is considered. The recoil pressure and the resulting force are formulated and the flexural displacement as well as the resulting stress fields are computed. The influence of the pressure force location at the assembly surface on the flexural motion is examined. It is found that the time occurrence of maximum flexural displacement is the same for all the load locations and the maximum displacement occurs at the free end of the cantilever assembly. The magnitude of normal stresses and shear stress is less than the yielding limit of the substrate material. Moreover, the maximum shear stress is almost three times the maximum normal stress in the assembly.

scholarly journals Finite Element Modeling of Residual Stress at Joint Interface of Titanium Alloy and 17-4PH Stainless Steel

Metals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 629
Author(s):  
Nana Kwabena Adomako ◽  
Sung Hoon Kim ◽  
Ji Hong Yoon ◽  
Se-Hwan Lee ◽  
Jeoung Han Kim
Keyword(s):  
Residual Stress ◽  
Finite Element ◽  
Stainless Steel ◽  
Finite Element Modeling ◽  
Equivalent Stress ◽  
Stress Gradient ◽  
Joint Interface ◽  
Element Modeling ◽  
Actual Experiment ◽  
Maximum Equivalent Stress

Residual stress is a crucial element in determining the integrity of parts and lifetime of additively manufactured structures. In stainless steel and Ti-6Al-4V fabricated joints, residual stress causes cracking and delamination of the brittle intermetallic joint interface. Knowledge of the degree of residual stress at the joint interface is, therefore, important; however, the available information is limited owing to the joint’s brittle nature and its high failure susceptibility. In this study, the residual stress distribution during the deposition of 17-4PH stainless steel on Ti-6Al-4V alloy was predicted using Simufact additive software based on the finite element modeling technique. A sharp stress gradient was revealed at the joint interface, with compressive stress on the Ti-6Al-4V side and tensile stress on the 17-4PH side. This distribution is attributed to the large difference in the coefficients of thermal expansion of the two metals. The 17-4PH side exhibited maximum equivalent stress of 500 MPa, which was twice that of the Ti-6Al-4V side (240 MPa). This showed good correlation with the thermal residual stress calculations of the alloys. The thermal history predicted via simulation at the joint interface was within the temperature range of 368–477 °C and was highly congruent with that obtained in the actual experiment, approximately 300–450 °C. In the actual experiment, joint delamination occurred, ascribable to the residual stress accumulation and multiple additive manufacturing (AM) thermal cycles on the brittle FeTi and Fe2Ti intermetallic joint interface. The build deflected to the side at an angle of 0.708° after the simulation. This study could serve as a valid reference for engineers to understand the residual stress development in 17-4PH and Ti-6Al-4V joints fabricated with AM.

scholarly journals Numerical Simulation and Experimental Study on Axial Stiffness and Stress Deformation of the Braided Corrugated Hose

2021 ◽  
Vol 11 (10) ◽  
pp. 4709
Author(s):  
Dacheng Huang ◽  
Jianrun Zhang
Keyword(s):  
Numerical Simulation ◽  
Geometric Model ◽  
Equivalent Stress ◽  
Element Model ◽  
Maximum Error ◽  
Structural Features ◽  
Axial Stiffness ◽  
Frictional Stress ◽  
Maximum Equivalent Stress ◽  
Simulation Results

To explore the mechanical properties of the braided corrugated hose, the space curve parametric equation of the braided tube is deduced, specific to the structural features of the braided tube. On this basis, the equivalent braided tube model is proposed based on the same axial stiffness in order to improve the calculational efficiency. The geometric model and the Finite Element Model of the DN25 braided corrugated hose is established. The numerical simulation results are analyzed, and the distribution of the equivalent stress and frictional stress is discussed. The maximum equivalent stress of the braided corrugated hose occurs at the braided tube, with the value of 903MPa. The maximum equivalent stress of the bellows occurs at the area in contact with the braided tube, with the value of 314MPa. The maximum frictional stress between the bellows and the braided tube is 88.46MPa. The tensile experiment of the DN25 braided corrugated hose is performed. The simulation results are in good agreement with test data, with a maximum error of 9.4%, verifying the rationality of the model. The study is helpful to the research of the axial stiffness of the braided corrugated hose and provides the base for wear and life studies on the braided corrugated hose.

Design Optimization for Fir-Tree Root of Turbine Blade Considering Manufacturing Variations

2013 ◽  
Vol 694-697 ◽  
pp. 2733-2737
Author(s):  
Qin Zhou ◽  
Ming Hui Zhang ◽  
Hui Yong Chen ◽  
Yong Hui Xie
Keyword(s):  
Particle Swarm Optimization ◽  
Turbine Blade ◽  
Equivalent Stress ◽  
Particle Swarm ◽  
Pattern Search ◽  
Design System ◽  
Contact Method ◽  
Swarm Optimization ◽  
Maximum Equivalent Stress ◽  
Manufacturing Variation

An optimization design system for fir-tree root of turbine blade has been developed in this paper. In the system, a parametric model of the blade and rim was established based on the parametric design language APDL, and nonlinear contact method was used for analysis by ANSYS, meanwhile some optimization algorithms, such as Pattern Search Algorithm, Genetic Algorithm, Simulated Annealing Algorithm and Particle Swarm Optimization, were adopted to control the optimizing process. Five cases of manufacturing variation in contact surfaces between root and rim were taken into account, and the design objective was to minimize the maximum equivalent stress of root-rim by optimizing eight critical geometrical dimensions of the root and rim. As a result, the maximum equivalent stress of root-rim decreases markedly after the optimization in all cases. In consideration of both precision and computing time, particle swarm optimization is assessed as the best algorithm to solve structure optimization problem in this work. Corresponding to five different cases of manufacturing variation, the maximum equivalent stress of root and rim reduces by 7%, 8%; 27%, 24%; 27%, 22%; 25%, 19%; 10%, 14% using the Particle Swarm Optimization.

Optimization design of titanium alloy connecting rod based on structural topology optimization

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Bin Zheng ◽  
Yi Cai ◽  
Kelun Tang
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Topology Optimization ◽  
Optimization Design ◽  
Equivalent Stress ◽  
Connecting Rod ◽  
Element Analysis ◽  
Content Type ◽  
The Finite Element Analysis ◽  
Maximum Equivalent Stress

Purpose The purpose of this paper is to realize the lightweight of connecting rod and meet the requirements of low energy consumption and vibration. Based on the structural design of the original connecting rod, the finite element analysis was conducted to reduce the weight and increase the natural frequencies, so as to reduce materials consumption and improve the energy efficiency of internal combustion engine. Design/methodology/approach The finite element analysis, structural optimization design and topology optimization of the connecting rod are applied. Efficient hybrid method is deployed: static and modal analysis; and structure re-design of the connecting rod based on topology optimization. Findings After the optimization of the connecting rod, the weight is reduced from 1.7907 to 1.4875 kg, with a reduction of 16.93%. The maximum equivalent stress of the optimized connecting rod is 183.97 MPa and that of the original structure is 217.18 MPa, with the reduction of 15.62%. The first, second and third natural frequencies of the optimized connecting rod are increased by 8.89%, 8.85% and 11.09%, respectively. Through the finite element analysis and based on the lightweight, the maximum equivalent stress is reduced and the low-order natural frequency is increased. Originality/value This paper presents an optimization method on the connecting rod structure. Based on the statics and modal analysis of the connecting rod and combined with the topology optimization, the size of the connecting rod is improved, and the static and dynamic characteristics of the optimized connecting rod are improved.

Thermo-mechanical analysis and optimization of functionally graded rotating disks

2020 ◽  
Vol 55 (5-6) ◽  
pp. 159-171
Author(s):  
Hassan Mohamed Abdelalim Abdalla ◽  
Daniele Casagrande ◽  
Luciano Moro
Keyword(s):  
Finite Element ◽  
Equivalent Stress ◽  
Rotating Disk ◽  
Mechanical Analysis ◽  
Theory Of Elasticity ◽  
Functionally Graded ◽  
Rotating Disks ◽  
Maximum Equivalent Stress ◽  
Quadratic Programming Method ◽  
Stress Uniformity

The behavior of thermo-mechanical stresses in functionally graded axisymmetric rotating hollow disks with variable thickness is analyzed. The material is assumed to be functionally graded in the radial direction. First, a two-dimensional axisymmetric model of the functionally graded rotating disk is developed using the finite element method. Exact solutions for stresses are then obtained assuming that the plane theory of elasticity holds. These solutions are in accordance with finite element ones, thus showing the validity of the assumption. Finally, in order to reduce the maximum equivalent stress along the radius, the optimization of the material distribution is addressed. To avoid subsequent finite element simulations in the optimization process, which can be computationally demanding, a nonlinear constrained optimization problem is proposed, for which the solution is obtained numerically by the sequential quadratic programming method, showing prominent results in terms of equivalent stress uniformity.

Investigation of Strength in G4-73 Type Centrifugal Fan Impeller

2011 ◽  
Vol 383-390 ◽  
pp. 5669-5673
Author(s):  
Song Ling Wang ◽  
Zhe Sun ◽  
Zheng Ren Wu
Keyword(s):  
Numerical Simulation ◽  
Finite Element Method ◽  
Finite Element ◽  
Calculation Result ◽  
Working Condition ◽  
Equivalent Stress ◽  
Centrifugal Fan ◽  
The Finite Element Method ◽  
Total Displacement ◽  
Maximum Equivalent Stress

For the large centrifugal fan impeller, its working condition generally is bad, and its geometry generally is complex. So its displacements and stresses distribution are also complex. In this paper, we can obtain the fan impeller’s displacements and stresses distribution accurately through numerical simulation in G4-73 type centrifugal fan impeller using the finite element method software ANSYS. The calculation result shows that the maximum total displacement of the impeller is m, it occurs on the position of the half of the blade near the outlet of the impeller; and the maximum equivalent stress of the impeller is 193 MPa, it occurs on the contacted position of the blade and the shroud near inlet of the impeller. Furthermore, check the impeller strength, the result shows that the strength of the impeller can meet the requirement.

Horizontal well of Shale Gas Complex Fracturing Casing Failure Mechanism

2019 ◽  
Vol 944 ◽  
pp. 898-902
Author(s):  
Shang Yu Yang ◽  
Jian Jun Wang ◽  
Guang Xi Liu ◽  
Li Hong Han
Keyword(s):  
Failure Mechanism ◽  
Shale Gas ◽  
Equivalent Stress ◽  
Great Influence ◽  
Distribution Law ◽  
Gas Well ◽  
Fracturing Process ◽  
Variable Function ◽  
Maximum Equivalent Stress ◽  
Casing Deformation

Shale gas well casing deformation failure is extremely serious in complex fracturing process. Based on the elastic mechanics theory, the distribution law of casing’s maximum equivalent stress field with the non uniform external extrusion is calculated by the complex variable function method. Meanwhile, casing deformation failure mechanism with non uniform external extrusion is revealed. For another, the maximum equivalent stress of the casing is analyzed with the case of a/b=2 and a/b=5. The result shows that the unevenness of the extrusion load has a great influence on the casing maximum equivalent stress distribution. The findings provide technical support for casing design and selection in complex fracturing process of shale gas well. Keywords: shale gas well; complex fracturing; casing formation; failure mechanism

Investigation of Material Properties of One-Piece Glass Fiber Post-and-Core Affecting Biomechanical Responses of the Restorative System

2010 ◽  
Vol 160-162 ◽  
pp. 1691-1698 ◽  
Author(s):  
Zhi Xin Huang ◽  
Cai Fu Qian ◽  
Peng Liu ◽  
Xu Liang Deng ◽  
Qing Cai ◽  
...  
Keyword(s):  
Shear Modulus ◽  
Young’S Modulus ◽  
Material Properties ◽  
Poisson’S Ratio ◽  
Young's Modulus ◽  
Equivalent Stress ◽  
Poisson's Ratio ◽  
Fiber Post ◽  
Maximum Deformation ◽  
Maximum Equivalent Stress

This study aimed at investigating the effects of the post material properties on the maximum stress in the root and maximum deformation of the restorative system. Effects of material properties of fiber post on the maximum equivalent stress in the root and the maximum deformation of the restorative system were numerically investigated. Results show that the maximum equivalent stress in the root can be decreased by 8.3% and the maximum deformation of the restorative system decreased by 10% compared with corresponding maximum values if changing Young’s modulus, Shear modulus and Poisson’s ratio in the range studied here. The maximum equivalent stress in the root is more sensitive to Young’s modulus and Poisson’s ratio while the deformation of the restorative system is more seriously affected by the Shear modulus of the post material.

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