Analytical Finite Element Analysis Research Articles

Case study of testing different materials for seat belt retractor torsion bar by the means of finite element analysis

This paper examines the use of various materials for the force limiter torsion bar found in an automotive seat belt assembly. We have selected the following materials: carbon steel, cast stainless steel, cast low alloy steel and cast aluminium alloy. The primary method used for this study is finite element analysis (FEA) and the use of the named materials on a 3D model of the torsion bar, constructed using the dimensions of a standard part. The 3D models were created with a 3D CAD program and the FEA analysis was carried out with special software. For the input values, the torsion bar was fixed at one corner and a 360 degree rotation shift at the other corner. A fine mesh of 1.5 mm/element was also set to get a more accurate analysis. The results of this study are in the form of stress, strain, safety factor and displacement plots generated by the FEA analysis software showing the difference between the materials. The main outcome of the study is to determine the best overall material to manufacture the part in terms of performance and cost.

A Buckling Instability Prediction Model for the Reliable Design of Sheet Metal Panels Based on an Artificial Intelligent Self-Learning Algorithm

Sheets’ buckling instability, also known as oil canning, is an issue that characterizes the resistance to denting in thin metal panels. The oil canning phenomenon is characterized by a depression in the metal sheet, caused by a local buckling, which is a critical design issue for aesthetic parts, such as automotive outer panels. Predicting the buckling instability during the design stage is not straightforward since the shape of the component might change several times before the part is sent to production and can actually be tested. To overcome this issue, this research presents a robust prediction model based on the convolutional neural network (CNN) to estimate the buckling instability of automotive sheet metal panels, based on the major, minor, and Gaussian surface curvatures. The training dataset for the CNN model was generated by implementing finite element analysis (FEA) of the outer panels of various commercial vehicles, for a total of twenty panels, and by considering different indentation locations on each panel. From the implemented simulation models the load-stroke curves were exported and utilized to determine the presence, or absence, of buckling instability and to determine its magnitude. Moreover, from the computer aided design (CAD) files of the relevant panels, the three considered curvatures on the tested indentation points were acquired as well. All the positions considered in the FEA analyses were backed up by industrial experiments on the relevant panels in their assembled position, allowing to validate their reliability. The combined correlation of curvatures and load-displacement curves allowed correlating the geometrical features that create the conditions for buckling instability to arise and was utilized to train the CNN algorithm, defined considering 13 convolution layers and 5 pooling layers. The trained CNN model was applied to another automotive frame, not used in the training process, and the prediction results were compared with experimental indentation tests. The overall accuracy of the CNN model was calculated to be 90.1%, representing the reliability of the proposed algorithm of predicting the severity of the buckling instability for automotive sheet metal panels.

Study of surface finishing mechanism in a rotational-magnetorheological miniature gear profile polishing using novel flow restrictor

Nano-finishing of miniature gear is a tough job since its geometry is complex. Traditional gear finishing methods can cause burns, micro-cracks, scratch marks, burrs, pits and thermal distortion in gear teeth profiles. Because of the limited spacing between the gear teeth, miniature gears can only be finished with a few processes. This article reports on the new uniform flow restrictor used in the rotational magnetorheological fluid-based finishing (R-MRFF) method to ensure a consistent and precise polishing of gear profiles. The uniform flow restrictor is analyzed using a commercial software program (COMSOL® Multiphysics) focused on finite element analysis (FEA). The surface roughness simulation is also performed using the results of the FEA and force analysis on active abrasives. The simulated roughness values are consistent with experimental values. Later, the experiments are performed without and with a novel uniform flow restrictor on the SS316L spur gear teeth profile to examine and compare the finishing performance. After finishing the gear, the minimum surface roughness of Ra = 23.9 nm at the tooth profile is achieved, and further, all manufacturing defects are entirely removed. Concurrently, the teeth geometry profiles are not affected. The uniform finishing of miniature gear with a continuous smooth surface may improve its work performance, transmitting power ability, reliability, fatigue life and form accuracy.

Experimental Investigation of the Magnetic Abrasive Finishing of SS310s

Abstract Magnetic abrasive finishing (MAF), an unconventional process, enhances the surface finish of a material. The current research focuses on its use with SS310s. The finite element analysis (FEA) result shows the effect of control parameters on the magnetic flux density. In FEA analysis, it was decided to maintain an air gap of 1.5-2 mm and a voltage of 10-20 V. A response surface methodology (RSM) desirability function is used to identify the optimal process parameters. Experiments are conducted for optimizing the process parameters like voltage, rotational speed, machining gap, mixing ratio, and mesh number to enhance the material removal rate (MRR) and surface roughness (Ra). A series of 62 experiments are conducted using optimized process parameters at different levels. Moreover, analysis of variance (ANOVA) is used to identify the percentage contribution of each process parameter in %ΔRa and MRR. From this, the mesh number of the abrasives plays an important role in the finishing process owing to the increased number of cutting edges and because of the uniform normal force (Fn) distribution. The optical microscopic image result and the wear test confirms that the surface finish of SS310s has been improved using MAF.

Development of Walking Robot Using Compliance Mechanism

Walking robot is a trend in this 21st century as Industrial Revolution 4.0 which involved automation has become a hot topic. Unlike ordinary moving robots, walking robots that take humans and animals as references can move on unpaved surfaces. Compliance mechanism is a flexible mechanism that transfers input force into output force through plastic deformation of certain members in the structure. A compliant structure can be classified as a monolithic structure that deforms elastically without any joint or linkage between the members. Unlike motorised robot legs requiring an input motion in each joint and link, a single input force can operate a compliant leg. Therefore, this research aims to develop a 3D printed compliant leg. This project is challenging because there is no reference for the single-piece compliant leg development using Three-Dimensional(3D) printing technology. The application of Jansen Linkage in the development of the compliant leg also results in difficulties because there is no standard equation for the calculation of each member in the Jansen Linkage. Hence, the development of the Jansen Linkage using different dimensions will solve these problems by varying the difference occurring upon changing the dimension. We also make Finite Element Analysis (FEA) of the product. The thesis will be supported by the walking motion pattern, force vs time graph and FEA analysis results for the product.

Design and simulation of mechanical press for testing of coining tools with nanostructured coatings

The present study proposes the design, simulation, and finite element analysis (FEA) of a mechanical press to test coining tools that contain nanostructured coatings. The designed mechanical testing press has a nominal force capacity of 800 kN with a ram stroke of 100 mm. CAD modeling of components, assemblies, and press structure is developed. The validation of the safety factor of the stress of the press is implemented by FEA analysis. Axisymmetric 2D FEA simulation is applied to determine the nanostructured coating behavior when subjected to high loads, the results are promising for future simulation studies on coatings. A displacement mechanism was designed for the test sheet, offering versatility and a variety of options for testing the coining tools as often as necessary under different load conditions. The final results of the machine operation simulation are satisfactory.

Influence of Cement Thickness on the Polymerization Shrinkage Stress of Adhesively Cemented Composite Inlays: Photoelastic and Finite Element Analysis

The objective of this study was to analyze the effect of cement thickness on the strain and stresses resulting from the polymerization of resin cement using photoelasticity and Finite Element Analysis (FEA). For this study, twenty upper first premolars with inlay cavity preparation were constructed from photoelastic resin and restored with composite resin inlay. The samples were divided into two groups (n = 10) according to the film thickness of resin cement material. For Group 1, the film thickness was 100 μm; for Group 2, the film thickness was 400 μm. After polymerization of the cement, photoelastic analysis and finite element analysis (FEA) were performed. In the photoelastic analysis, Group 2 showed higher strain with the presence of second-order fringe even after 24 h. In Group 1, the formation of first order fringes was not observed, even after 24 h. In the FEA analysis, the greatest cusp deflection and tensile stress occurred in Group 2 (0.00026 mm and 0.305 MPa, respectively) due to the polymerization shrinkage in the lingual cusp compared to Group 1 (0.000107 mm and 0.210 MPa, respectively). It can be concluded that the thickness of the resin cement influences the cusp deflection, with the greater thickness of the cement layer, the greater stresses and deformations in the tooth structure occur.

Reduction of Cogging Torque in Surface Mounted Permanent Magnet Brushless DC Motor by Adapting Rotor Magnetic Displacement

Cogging torque is a critical dilemma in Permanent Magnet Brushless DC (PMBLDC) motors. In medium-low power PMBLDC motors, redundant vibrations and forbidding noises arise as a result of the harmonic magnetic forces created by cogging torque. This paper introduces a simple approach for minimizing cogging torque in PMBLDC motors by applying placement irregularities in rotor magnets. An angle shift in the rotor magnets in surface-mounted PMBLDC motors helps to attain magnet displacement. This displacement imparts an asymmetrical magnet structure to the rotor. Maintaining pole arc to pole pitch ratio (L/τ) of between 0.6 and 0.8, shifting angles from 1° to 8° were considered in order to analyze the effect of the angle shift on the rotor magnets. An analytical expression was also derived for finding the shifting angle with the minimum cogging torque in the PMBLDC motor by using the Virtual Work Method (VWM). The optimization of the shifting angle with minimum cogging torque was investigated using 3D Finite Element Analysis (FEA). A comparison of the simulation and analytical results of cogging torque was carried out. It was determined that the reduction of cogging torque in the analytical results showed good agreement with the FEA analysis.

Topology optimization of clutch drive plate for commercial vehicles

he drive plate is one of the main components of the clutch disc which transmits the torque from engine to transmission. For commercial vehicle applications, the drive plate works under immense torsional forces thanks to high engine torque values. Therefore, high durability is expected during the operational life of the clutch disc drive plate. On the other hand, the lightweight of the vehicle components has an important role in CO2 emission standards. To be able to assure this regulation, companies conduct studies for decreasing the vehicle mass. In this study, the drive plate's 3D CAD data is created based on the current design by using CATIA solid creation software. Finite Element Analysis (FEA) was carried out in a statical analysis tool and to be verified for real-life working conditions. The topology optimization was performed using CAE software (ANSYS) in order to reduce the weight of the drive plate without compromising on mechanical durability. The optimized design was proposed based on topology optimization outputs. The strength of the proposed design was investigated by using FEA analysis and results are compared to the acceptance criteria of the material. The optimized geometry is equally durable and lighter in weight compared to the existing model. Mass was decreased %18 without compromising mechanical durability.

Torque analytical model and self‐decoupling characteristics analysis of a bearingless switched reluctance motor

In this paper, a bearingless switched reluctance motor (BRSM) with sharing suspension windings, which simplifies the winding structure and reduces the complexity of the control circuit, is analysed. A torque analytical model is derived using the Maxwell stress tensor method, which provides better results, compared with the linear model in the magnetic saturated conditions. A finite element analysis (FEA) model of the prototype is built and used for comparison with the torque analytical model. The results show that the torque analytical model provides accurate results in the entire magnetic saturation region, which verify the feasibility of this model. In addition, the self-decoupling characteristics of this type of motor are illustrated using analytical model analysis, FEA and experimental analysis. The results indicate that BSRMs with sharing suspension windings can be flexibly controlled without using complex self-decoupling algorithms of conventional BSRMs. The presented work provides a theoretical basis for the control strategy.

Exploring barriers for the use of FEA-based variation simulation in industrial development practice

Abstract Over the last decades, finite element analysis (FEA) has become a standard tool in industrial product development, allowing for virtual analysis of designs, quick turnaround times and prompt implementation of results. Although academic research also provides numerous approaches for evaluating a product’s robustness towards geometrical, material and load variations based on FEA analyses, this, however, stands in striking contrast to the limited use of these FEA-based variation simulations in industry. In order to bridge the existing gap between academic research and industrial application, this paper explores the barriers that limit the adoption of FEA-based variation simulation. The investigation is based on interviews with five lead engineers, followed by a case study that details the underlying technical challenges and allows for some initial suggestions for future solutions. The case study involves a sterile canister with seven geometrical variables. The design objective is to ensure sufficient sealing within the range of expected probabilistic variation. The combined study details the identified main barriers for a wider application, that is, the lack of robust CAD, practical guidelines to select an efficient design of experiments for design purposes, and the complexity of the automated processes. From a technical perspective, the case study results in estimations for main and interaction effects, an accurate metamodel and Monte Carlo simulations of 100,000 samples providing the design engineer with more detailed and actionable insights on the performance of the product compared with the traditional nominal or best/worst case simulations.

Optimization of UAV structure and evaluation of vibrational and fatigue characteristics through simulation studies

Unmanned Aerial Vehicles (UAV) is generic air vehicles that are significantly developed for military and civil purposes. In recent times, advancements in the field of UAVs are exceptional and tremendous. Nevertheless, numerous researches have been performed mainly to reduce the weight of the UAV structure. The flight time and allowable payload rely on the UAV structure's weight, which is considered a significant factor. Hence, in this paper, the UAV model's static structural behavior is cultivated utilizing the morals of Finite Element Analysis (FEA) to determine the total deformation and Von-mises stress. Three different polymer materials, namely Poly Lactic Acid (PLA), Acrylonitrile Butadiene Styrene (ABS), and Polyamide (PA), are chosen for FEA analysis of 3D printed UAV structure. The thrust generated from the motors varies from 2 kg to 5 kg, and an evaluation of structural strength characteristics is performed. The FEA study has shown that maximum deformation and maximum stress are obtained at the propeller casings and the basement of the structure, respectively. After comparing the details on deformation and stress from all three materials, the research also reveals that PLA is the best material for conception. Furthermore, topological optimization is performed on the UAV structure to reduce mass and minimize stress without compromising mechanical strength. The vibrational and fatigue characteristics of optimized UAV structure is examined. The unified body of the UAV frame will reduce the assembly time and make manufacturing much more effortless.

FEA analysis of ballistic impact on carbon nanotube bulletproof vest

Personal body armor has surfaced in a variety of different forms throughout the centuries. Today, bulletproof vests serve as a lightweight armor technology designed to protect the wearer from critical internal injuries caused by firearm projectiles. These bulletproof vests are predominantly manufactured by using Kevlar. Though Kevlar has adequate absorption capacity, its strength to withstand bullet comes with the addition of Kevlar layers, which adds up to the body armor's weight. Carbon Nanotubes (CNTs) are of great area of interest nowadays due to their exceptional mechanical properties. It is much lighter and possesses higher strength when compared to Kevlar. This study focuses on the Finite Element Analysis (FEA) of bulletproof vest made up of CNTs. Furthermore, it also gives a comparative study of Carbon nanotubes and Kevlar 29 in ballistic applications.

Polyether ether ketone - As an alternative biomaterial for Metal Richmond crown-3-dimensional finite element analysis.

Aim:This study was aimed to analyze the stress generation and distribution for “polyether ether ketone (PEEK)” and metal cobalt-chromium (Co-Cr) at different locations of the tooth using finite element analysis (FEA), when they are casted-off as “Richmond crowns.”Materials and Methods:The model of the tooth was designed using “computer-aided design/computer-aided manufacturing” followed by generating the “Mesh” of the tooth to analyze the stress caused by applying vertical and oblique loads of 100N and 40N, respectively, in cubical nodes for both PEEK and metal endodontic post-based Richmond crown. The “3-dimensional von Mises criteria” was used to compare stresses of both elements using FEA. The material properties for each component were designated by respective modulus of elasticity and Poisson's ratio. The statistical test of the stress generation in various locations of PEEK and Metal (Co-Cr) Richmond crown was done by independent t-test.Results:From the FEA analysis of Richmond crown, it is evident that maximum stress was generated by “Metal” of about 66.418 MPa when compared to “PEEK” (15.826 MPa). “PEEK Richmond crown” produced minimal stress on the tooth and the other surrounding regions than “Metal Richmond crown” with a statistically significant difference (P < 0.05).Conclusion:The results proved that the “Metal Richmond crown” postsystem had a tendency to produce more stress on the tooth and the other surrounding regions than the PEEK. The FEA proved the pros of using “PEEK post Richmond crown,” which is a big boon for the modern era dentistry.

Increasing force generation in electroadhesive devices through modelling of novel electrode geometries

Two approaches were taken to increase the obtainable electroadhesive (EA) forces from EA electrode devices using finite element analysis (FEA): (i) optimising electrode widths and spacings using 2D parametric simulations; and (ii) optimising electrode geometries using 3D simulations. The Maxwell stress distributions generated by the simulated EA pads are reported; and illustrate how electrode geometries influence the EA forces generated. The FEA analyses were carried out using ANSYS MAXWELL with an automatic adaptive mesh refinement (AMR) technique which accelerates convergence and decreases the number of elements needed for study of mesh independency. The 2D parametric FEA shows optimum electrode widths of 2.6 mm and optimum spacing between electrodes of 0.2 mm for an effective surface of EA pads. 3D FEA shows that from the studied EA pads with a constant effective area, sine-wave shaped electrodes can generate substantially enhanced EA forces compared to other electrode geometries. This is attributed to maximising the electric field gradient and could benefit multiple applications. The simulation procedure is also validated by real-world problems.

Performance comparison of partitioned primary hybrid excited linear flux switching machine

To avoid the problem of crowded primary and rising temperature of permanent magnet (PM), the design of partitioned primary hybrid excited linear flux switching machine (PP-HLFSM) positions the armature, and field excitation coil winding on separate part of the mover. This article examines the performance analysis of different structures of unaligned structure of PP-HLFSM and compared the proposed designs by reducing the usage of PM to half in terms of volume from 25,920 mm3 to 12,960 mm3, for both concentrated and toroidal winding structure leading toward cost effectiveness. This article scales down the cost of proposed designs for elevator long stroke application. Based on finite element analysis (FEA) and boundary element analysis, the electromagnetic performance of the machine is studied in detail. Single variable optimization is implemented to optimize both the proposed structures. Analysis includes flux linkages, flux strengthening, average force characteristics, force–velocity and power–velocity curves, copper losses, iron losses, efficiency, thrust force density and power density, and demagnetization analysis. Comparison of conventional structure with proposed designs are made in terms of flux, thrust force, losses, efficiency, power density, demagnetization of PMs, and thermal analysis, along with 3D FEA analysis. Finally, the proposed structures are analytically validated.

The Seismic Safety Assessment of 170 kV GIS (Gas-Insulated Switchgear) by the Seismic Test on the Large Shaking Table and by the Finite Element Analysis with Korean and IEC Seismic Standards

This paper describes the seismic test and numerical stress analysis of a 170 kV Gas-insulated switchgear (GIS) to see the structural and operational safety. Both the seismic test and numerical FEA (finite element analysis) are performed according to the procedure of Korean and International (IEC-62271) seismic standards. The GIS is mounted on the shaking table for a seismic test at KIMM (Korea Institute of Machinery and Material) to see the stress level and safety under earthquake loading conditions. The FEA analysis is performed to compare with the seismic test. Both the natural frequency (NF) and stress results from the numerical computation and seismic test are close and show adequate electrical and structural safety margin.

Analisis Kekuatan Flange Valve Akibat Pengaruh Bolt Torque pada Kondisi Pressure dan Temperature Berbeda dengan Metode Finite Element Analysis

Sistem penyambungan pipa yang terhubung dengan valve (katup) menggunakan sambungan flange. Hal ini bertujuan untuk memudahkan memasang atau melepaskan sambungan pada saat diperlukan. Sistem penyambungan ini meliputi sambungan pipa ke fitting, valve, equipment, atau bagian lainnya yang merupakan bagian terpisah dalam sistem pemipaan. Analisis kekuatan flange pada ball valve 4 inch ANSI 300 bertujuan untuk mengetahui dan memastikan bahwa flange memiliki kekuatan dan aman pada saat lepas pasang akibat pengaruh Bolt Torque. Selain itu, untuk memastikan sambungan tidak bocor pada saat dilalui fluida. Kombinasi utama antara tekanan internal, aksial dan pembebanan termal perlu dipertimbangkan. Analisis kekuatan flange menggunakan metode Finite Element Analysis (FEA) dengan bantuan software Solid works. Analisis kekuatan flange menggunakan metode “Flange as weakest part philosophy” yaitu full rating yang dipakai bila nilai pressure-temperature tertentu pada ASME B16.5 yang diambil untuk Tekanan Kerja Maksimum yang diijinkan atau Maximum Allowable Working Pressure (MAWP) pada sistem perpipaan. Dari hasil analisis FEA, diperoleh bahwa flange pada ball valve 4 inch ANSI 300 memenuhi syarat sesuai dengan MAWP pada temperatur dan tekanan berbeda. Nilai safety factor juga menunjukkan bahwa flange aman pada saat proses kerja pemipaan.

Biomechanical Behavior of Bioactive Material in Dental Implant: A Three-Dimensional Finite Element Analysis.

Dental implants are widely accepted for the rehabilitation of missing teeth due to their aesthetic compliance, functional ability, and great survival rate. The various components in implant design like thread design, thread angle, pitch, and material used for manufacturing play a critical role in its success. Understanding these influencing factors and implementing them properly in implant design can reduce cases of potential implant failure. Recently, finite element analysis (FEA) is being widely used in the field of health sciences to solve problems in designing medical devices. It provides valid and accurate assessment in the clinical and in vitro analysis. Hence, this study was conducted to evaluate the impact of thread design of the implant and 3 different bioactive materials, titanium alloy, graphene, and reduced graphene oxide (rGO) on stress, strain, and deformation in the implant system using FEA. In this study, the FEA model of the bones and the tissues are modeled as homogeneous, isotropic, and linearly elastic material with a titanium implant system with an assumption of it 100% osseointegrated into the bone. The titanium was functionalized with graphene and graphene oxide. A modeling software tool Catia® and Ansys Workbench® is used to perform the analysis and evaluate the von Mises stress distribution, strain, and deformation at the implant and implant-cortical bone interface. The results showed that the titanium implant with a surface coating of graphene oxide exhibited better mechanical behavior than graphene, with mean von Mises stress of 39.64 MPa in pitch 1, 23.65 MPa in pitch 2, and 37.23 MPa in pitch 3. It also revealed that functionalizing the titanium implant will help in reducing the stress at the implant system. Overall, the study emphasizes the use of FEA analysis methods in solving various biomechanical issues about medical and dental devices, which can further open up for invivo study and their practical uses.

Assessing Thermomechanical Fatigue of a Cast Aluminum Alloy Cylinder Head of an Internal Combustion Engine

&lt;div class="section abstract"&gt;&lt;div class="htmlview paragraph"&gt;Cast aluminum alloys are used for cylinder heads in internal combustion engines to meet low weight and high strength (lightweight) design requirements. In the combustion chamber, the alloy experiences harsh operating conditions; i.e., temperature variation, constrained thermal expansion, chemical reaction, corrosion, oxidation, and chemical deposition. Under these conditions, thermomechanical fatigue (TMF) damage arises in the form of mechanical damage, environmental (oxidation) damage, and creep damage.&lt;/div&gt;&lt;div class="htmlview paragraph"&gt;In the present work, several important properties that influence the TMF life of the cylinder head have been identified through TMF and finite element analysis (FEA). The results show that improving the strength at high temperatures helps improve TMF life on the exhaust side of the head. On the other hand, improving strength and ductility extend TMF life at low temperature on the intake side. Based on Neu-Sehitoglu TMF damage model, environmental (oxidation) damage is responsible for more than 80% of the total damage on the exhaust side. On the intake side, environmental factors are again a significant contributor to overall damage, but produce a smaller portion of total damage as compared to the exhaust side. Damage due to creep, relative to other categories of damage, is minimal and can therefore be neglected. Environmental (oxidation) damage is strongly influenced by the activation energy for oxidation. A small increase of the activation energy significantly increases the TMF life. The activation energy for oxidation is closely related to the chemical composition of the alloy and the kinetics of oxidation of each element in the alloy. FEA and TMF analysis facilitate optimized selection of target alloys that meet TMF life expectations as engine output increases.&lt;/div&gt;&lt;/div&gt;