ANSYS V12 Research Articles

Distinguishing process - impact of down milling and up milling in machining aluminium thin wall

The study aims to understand the deformation mechanics that occurs during down and up milling of aluminium thin wall fabrication. With cutting forces as inputs, material properties were defined by the Coffin-Manson relation and the Smith-Watson-Topper model. Hysteresis was found in the process of machining aluminium thin walls. Furthermore, the pattern of cutter loads differentiated the up and down milling through hysteresis. The finite element method was followed using ANSYS v14.5 software in the fatigue workbench to analyse the aspect. Down milling introduced both deflection and deformation. Conversely, up milling did not exhibit deflection. However, the Bauschinger effect and distinct fracture surfaces were diagnosed during up milling. By exploring the nature of hysteresis and fracture surfaces, the selection of down and up milling was made.

Torque Comparison Between Two Passive Self-Ligating Brackets with Respect to Interbracket Wire Dimensions and Types: A Finite Element Analysis

Objective: This study aimed to analyze the expression of torque between 2 passive self-ligating brackets by simulating different clinical situations using finite element analysis. Material and Methods: Two passive self-ligating brackets, that is, Damon Q (Ormco, Glendora, California) and Smart Clip (3M Unitek, Monrovia, California), were 3D modeled using micro-computed tomography. ANSYS V14.5 software was used for analysis. Archwire and bracket interactions were simulated to measure torque expression by changing wire alloys (stainless steel [SS] and titanium molybdenum [TMA]) and interbracket dimensions. Results: Damon Q brackets generated higher torque values compared to Smart Clip brackets with both SS and TMA wires. Damon Q brackets generated the highest torquing moment of 25.72 Nmm and 7.45 Nmm, while Smart Clip brackets generated 22.25 Nmm and 7.31 Nmm with 0.019 × 0.025″ SS and TMA wires, respectively, at an interbracket distance of 12 mm. Torquing moments decreased for Damon Q and Smart Clip brackets when wire length increased from 12 mm to 16 mm. Conclusion: Damon Q with 0.019 × 0.025″wires exhibited superior torquing characteristics as compared to Smart Clip brackets with similar archwires.

Comparative study of effect of web openings on the strength capacities of steel beam with trapezoidally corrugated web

In steel I beams the corrugated webs are sometimes used as an alternative to plain web in many steel construction. The idea behind this concept is an increase in the shear capacity of steel beams without providing the transverse stiffeners. The recent development in steel construction is the used of web openings for the utilization of various technical utilities in web. This paper presents an extensive parametric study on the steel beam with corrugated web having openings in the web. The objective of the present study is to observe the structural performance of this special type of beam towards the strength capacities. In the parametric study 60 models of steel beams with trapezoidally corrugated web with opening has been analyzed by finite element analysis using ANSYS v12. The variables in the present study are angle of corrugation, thickness of web and diameter of opening. The angle of corrugation, web thickness and diameter of web openings considered in the study are 0°, 30°, 45° and 3 mm, 4 mm, 5 mm and 0.5, 0.6, 0.75 times the overall depth of beam, respectively. The parametric study shows that lesser the angle of web corrugation, the more increase in the load carrying capacity is obtained. Ultimate strength capacity of 30° corrugated web beam with different diameter of opening such as 0.5 D, 0.6 D, and 0.75 D is found to be 15.27%, 14.83%, 9.72%, which is more than the beam with plain web. The height to thickness (h/tw) ratio considered in the study are 30, 37.5, 40, 50, and 66.67, respectively. The height to thickness (h/tw) ratio is found to be the main parameter influencing the buckling behaviour of steel beam with corrugated web.

Flexural Behavior of Hybrid Composite Beam (HCB) Bridges

A new hybrid composite beam (HCB) has recently been used in the construction of three bridges in Missouri, USA. HCB consists of self-consolidating concrete (SCC) that is poured into classical arch shape and tied at the ends by steel tendons. Both the concrete and the steel are tucked inside a durable fiberglass shell, and the voids are filled with polyiso foam. This paper aims to examine the flexural behavior of an in-service HCB, evaluate the current methodology and assumptions, and propose modifications to that methodology. To achieve these goals, the strains induced in HCB elements due to different loading stages were experimentally measured. Numerical predictions of the strains were performed via the existing methodology, the modified procedure, and a finite element model (FEM) that was constructed using ANSYS V14. The linear FEM predicted the strains with acceptable accuracy. The model clarified that the foam achieves partial composite action between the HCB elements, resulting in a strain incompatibility between them. The current methodology was found to be unable to predict the maximum compressive strain in the concrete arch. The modified procedure is based on the strain compatibility assumption. However, it models the HCBs as curved beam rather than a straight one, using a simplified spring model to represent the beam supports. These modifications achieved significant enhancements in estimating the strains under service loads.

Pre-drilling and self-drilling pins screw-bone fixation stress interaction analysis induced by uniaxial compression loading

A newly designed Uniaxial external fixator which functions as a universal fixator in the application of all types of bone fractures is recently introduced by both Hospital Universiti Kebangsaan Malaysia (HUKM) and Universiti Malaysia Perlis (UniMAP). The Investigation is focused on identifying and measuring the performance in terms of strength or weakness of the fixator that is needed before the application to the human body. Hence, this research was conducted to determine the performance of Uniaxial external fixator which was based on geometry using different screw drilling techniques applied during an angled uniaxial compression load. A three-dimensional fixator-bone was constructed using different screw inserting techniques which was then converted into ANSYS v14.5 for the purposes of conducting a finite element analysis (FEA). Axial compressive loading with various degrees from 60 to 6300 N were applied to bone models to stimulate patient’s daily activities while 10 to 100 N were applied to fixator models for the purposes of reviewing environmental loading to fixator-bone models. Findings revealed that maximum magnitude which caused deformation for predrilling and self-drilling models were located at the highest pin-bone interaction. Conversely, the maximum magnitude of the von Mises strain and stress was located at the lowest pin-bone interaction by omitting the existence of fixator for both Case 1 and 2. There was no obvious difference in the comparison of both models in terms of deformation. However, predrilling models have higher strain and stress than self-drilling models. In sum, findings indicated that self-drilling models have better performance compared to the predrilling models.

Contact Stress Analysis of Spur Gear Under the Different Rotational Speed by Theoretical and Finite Element Method

In this study that spur gears are chosen, contact stress of spur gear is presented under the effect of rotational speed. Three-dimensional simulation of dynamic analysis of gears designed and modeled using ANSYS software. The dynamic analysis included in the determination of dynamic stresses analysis. Contact stress is theoretically calculated and analyzed and numerically estimated using both Hertzian mathematical model and finite element method respectively. Different values of rotational speed used to study its effect on contact stress. Both methods compared by evaluating the percentage error of contact stress, and the modeling of the spur gear and stress analysis of spur gear carried out using SOLID WORK and ANSYS V14, respectively. The most significant note in this study concludes that increasing speed causes vibration and pitting failure due to repetitions.

Nonlinear Finite Element Analysis of Reinforced Concrete Beams Strengthened with Externally Bonded Steel Plate using ANSYS

The present work presents a numerical study to simulate the behavior of reinforced concrete beams strengthened with steel plates. The study is carried out using two un-strengthened RC beams and two RC beams strengthened with (1mm, and 3mm) steel plates. The beams are modeled and analyzed by nonlinear FEM using ANSYS v14.5. The numerical results are in good agreement with experimental load-displacement curves and ultimate load carrying capacity.

Finite element analysis of reinforced concrete beams with opening strengthened using FRP

Abstract Transverse openings are often provided through reinforced concrete beams to accommodate utility ducts and pipes. Finite element analysis has been used in order to study this problem. Fifty-seven beams analyzed using finite element program ANSYS V12. The analysis results compared with fifteen experimental beams had been done by Ibrahim. Study beams have opening width and height of dimensions 200 × 100 mm and 300 × 100 mm. The centerline of the opening is at distance of 225, 300, 350 and 400 mm from the near support. Strengthening of all beams with opening came out to six types of different scheme around the opening using fiber-reinforced polymer (FRP). Scheme (1) is vertical and horizontal carbon fiber sheets around the opening, scheme (2) is inclined at 45° carbon fiber sheets around the opening in addition to horizontal one, schemes (3) and (4) are same of schemes (1) and (2) respectively but with glass fiber sheets, while schemes (5) and (6) are same as schemes (3) and (4) respectively but with an additional strengthening at flexural area at the middle of the beam with U shape. The reinforced concrete beams were modeled in ‘ANSYS V12’ Program under statical load. The failure loads, crack pattern, strain progress, mode of failure and energy absorption were analyzed here in this study.

MOULD FLOW AND STRUCTURAL ANALYSIS OF INJECTION MOULD TOOL FOR HOOTER BODY COVER COMPONENT

Injection moulding is process of manufacturing plastics products from both thermo and thermosetting plastic materials. This paper presents the part modeling, design of core-cavity and side core by using SOLID WORKS 2012, the mould flow analysis is carried out by MOLD FLOW ADVISOR 2105 and static structural analysis performed using ANSYS V14.5. The mould tool is of single cavity mould and material planned for producing the component is polypropylene (pp)

The Effects of Fluid Structure Interactions on the Dynamic Characteristics of the Reactor Internals Structure of SMART

The Korea Atomic Energy Research Institutes has been developing the SMART (System integrated Modular Advanced ReacTor), an environment-friendly nuclear reactor, for the generation of electricity, and to perform desalination. SMART reactors can be exposed to various external and internal loads caused by seismic and coolant flows. Reactor structures need to be maintained for the reactor’s safety and integrity against these loads during the operational time of the SMART. This paper presents two FE-models, 3-D solid models of the reactor internals in the air and in the coolant, and then compares the results of the dynamic characteristic for the two FE-models using a commercial Finite Element tool, ANSYS V12. A solver was selected by the Block Lanczos method. These FE-models are looking forward to being executed in various researches concerning the SMART in further studies.

Preliminary Numerical Analysis of a Platform Structure

Finite element analysis (FEA) has become an increasingly important tool in evaluating structural performance of platforms. This includes the use of this tool to perform strength, stability checks, optimisation of structural design upon subjected to design loads as well as to perform failure investigation of platforms upon subjected to special loading conditions such as impacts. Traditionally, small and medium enterprises utilises laboratory (physical) testing and heuristic experience to fabricate and test the platforms, nonetheless this approach is deemed too time consuming and cost demanding. Therefore, this study aims at reconstructing the actual design based on engineering drawings as well as performing stress analysis by means of a commercial FEA software package, ANSYS v14.0 by investigating the effects of two distinct loading impacts on a mild steel platform. The maximum stress and maximum displacement values obtained via the FEA simulation was then compared with values obtained via theoretical computation. The results obtained via the FEA simulation was found to be in good agreement with the exact solution. The present study is non-trivial as it contributes towards the knowledge in the design and optimisation of complex steel structures.

Experimental investigation on vibration characteristics of woven carbon fabric-reinforced composite beams of various cross-sectional shapes

Vibration characteristics of carbon/epoxy composite beams await increased attention in structural industries such as aerospace, automotive, machine tools, marine industries. The objective of the present work is to investigate and analyze the shape effects of carbon/epoxy composite beams on vibration behavior. Specimens were fabricated using woven carbon fabric for basic shapes: I, box, and channel sections by hand layup method. The fabricated beams were subjected to impulse frequency response test under cantilever and fixed-end boundary conditions for free vibration test up to 3.5 kHz. Vibration response was measured using piezoelectric transducer and was recorded using computer-controlled data acquisition system for analyzing its behavior. The vibration characteristic of beams with various shapes shows modified performance under different boundary conditions. The experimental mode shapes and modal frequencies of beams are discussed and compared for successive resonance sets. At a lower frequency range of 3.5 kHz, the experimental modal responses of beam that were compared with modal results of finite element method analysis using software ANSYS V12® exhibited acceptable deviation in error maximum of up to 8.2%. Further, all deformed mode shapes of various shaped beams tested at increased frequency level of 12 kHz using finite element software were also observed and discussed.

Posterior cruciate ligament balancing in total knee arthroplasty: a numerical study with a dynamic force controlled knee model.

BackgroundAdequate soft tissue balancing is a key factor for a successful result after total knee arthroplasty (TKA). Posterior cruciate ligament (PCL) is the primary restraint to posterior translation of the tibia after cruciate retaining TKA and is also responsible for the amount of joint compression. However, it is complex to quantify the amount of ligament release with its effects on load bearing and kinematics in TKA and limited both in vivo and in vitro. The goal of this study was to create a dynamic and deformable finite element model of a full leg and analyze a stepwise release of the PCL regarding knee kinematics, pressure distribution and ligament stresses.MethodsA dynamic finite element model was developed in Ansys V14.0 based on boundary conditions of an existing knee rig. A cruciate retraining knee prosthesis was virtually implanted. Ligament and muscle structures were simulated with modified spring elements. Linear elastic materials were defined for femoral component, inlay and patella cartilage. A restart algorithm was developed and implemented into the finite element simulation to hold the ground reaction force constant by adapting quadriceps force. After simulating the unreleased PCL model, two models were developed and calculated with the same boundary conditions with a 50% and 75% release of the PCL stiffness.ResultsFrom the beginning of the simulation to approximately 35° of flexion, tibia moves posterior related to the femur and with higher flexion anteriorly. Anterior translation of the tibia ranged from 5.8 mm for unreleased PCL to 3.7 mm for 75% PCL release (4.9 mm 50% release).A decrease of maximum von Mises equivalent stress on the inlay was given with PCL release, especially in higher flexion angles from 11.1 MPa for unreleased PCL to 8.9 MPa for 50% release of the PCL and 7.8 MPa for 75% release.ConclusionsOur study showed that dynamic FEM is an effective method for simulation of PCL balancing in knee arthroplasty. A tight PCL led in silico to more anterior tibia translation, a higher collateral ligament and inlay stress, while retropatellar pressure remained unchanged. Surgeons may take these results in vivo into account.

Unconventional Bearing Capacity Analysis and Optimization of Multicell Box Girders

This study deals with unconventional bearing capacity analysis and the procedure of optimizing a two-cell box girder. The generalized model which enables the local stress-strain analysis of multicell girders was developed based on the principle of cross-sectional decomposition. The applied methodology is verified using the experimental data (Djelosevic et al., 2012) for traditionally formed box girders. The qualitative and quantitative evaluation of results obtained for the two-cell box girder is realized based on comparative analysis using the finite element method (FEM) and the ANSYS v12 software. The deflection function obtained by analytical and numerical methods was found consistent provided that the maximum deviation does not exceed 4%. Multicell box girders are rationally designed support structures characterized by much lower susceptibility of their cross-sectional elements to buckling and higher specific capacity than traditionally formed box girders. The developed local stress model is applied for optimizing the cross section of a two-cell box carrier. The author points to the advantages of implementing the model of local stresses in the optimization process and concludes that the technological reserve of bearing capacity amounts to 20% at the same girder weight and constant load conditions.

A Study of the Combined Effects of Erosions, Cracks and Partial Autofrettage on the Stress Intensity Factors of a Thick Walled Pressurized Cylinder

For the investigation of cracked problems in thick-walled pressurized cylindrical vessels, the displacement-based finite element method has become one of the main computational tools to extract stress intensity results for their fatigue life predictions. The process of autofrettage, practically from the partial autofrettage level of 30% to full autofrettage level of 100%, is known to introduce favorable compressive residual hoop stresses at the cylinder bore in order to increase its service life. In order to extract the fatigue life, stress intensity factors (SIFs) need to be obtained a priori. The necessity for determining SIFs and their practical importance are well understood. However, it is usually not a trivial task to obtain the SIFs required since the SIFs largely depend on not only the external loading scenarios, but also the geometrical configurations of the cylinder. Our recent work has shown that the Bauschinger effect (BE) may come into play and affect the effective SIFs significantly for an eroded fully autofrettaged thick-walled cylinder. In this study, we further investigate the SIFs for the Bauschinger effect dependent autofrettage (BEDA) and the Bauschinger effect independent autofrettage (BEIA) at various autofrettage levels. The crack is considered to emanate from the erosion's deepest point in a multiply eroded cylinder. The commercial finite element package, ANSYS v12, was employed to perform the necessary analysis. A two-dimensional model, analogous to the authors' previous studies, has been adopted for this investigation. The residual stress field of autofrettage process, based on von Mises yield criterion, is simulated by thermal loading. The combined SIFs are evaluated for a variety of relative crack lengths with cracks emanating from the tip of erosions with various geometrical configurations and span angles. The effective SIFs for relatively short cracks are found to be increased by the presence of the erosion and further increased due to the BE at the same autofrettage level, which may result in a significant decrease in the vessel's fatigue life. Deep cracks are found to be almost unaffected by the erosion, but may be considerably affected by BE as well as by the level of partial autofrettage.

Critical Assessment of Temperature Distribution in Submerged Arc Welding Process

Temperature distribution during any welding process holds the key for understanding and predicting several important welding attributes like heat affected zone, microstructure of the weld, residual stress, and distortion during welding. The accuracy of the analytical approaches for modeling temperature distribution during welding has been constrained by oversimplified assumptions regarding boundary conditions and material properties. In this paper, an attempt has been made to model the temperature distribution during submerged arc welding process using finite element modeling technique implemented in ANSYS v12. In the present analysis, heat source is assumed to be double-ellipsoidal with Gaussian volumetric heat generation. Furthermore, variation of material properties with temperature and both convective and radiant heat loss boundary condition have been considered. The predicted temperature distribution is then validated against the experimental results obtained by thermal imaging of the welded plate, and they are found to be in a good agreement.

Anatomical evaluation and stress distribution of intact canine femur

In the biomedical field, three-dimensional (3D) modeling and analysis of bones and tissues has steadily gained in importance. The aim of this study was to produce more accurate 3D models of the canine femur derived from computed tomography (CT) data by using several modeling software programs and two different methods. The accuracy of the analysis depends on the modeling process and the right boundary conditions. Solidworks, Rapidform, Inventor, and 3DsMax software programs were used to create 3D models. Data derived from CT were converted into 3D models using two different methods: in the first, 3D models were generated using boundary lines, while in the second, 3D models were generated using point clouds. Stress analyses in the models were made by ANSYS v12, also considering any muscle forces acting on the canine femur. When stress values and statistical values were taken into consideration, more accurate models were obtained with the point cloud method. It was found that the maximum von Mises stress on the canine femur shaft was 34.8 MPa. Stress and accuracy values were obtained from the model formed using the Rapidform software. The values obtained were similar to those in other studies in the literature.