Finite Element Analysis Approach Research Articles

Finite Element Analysis of Stress Distribution in Cancellous Bone During Dental Implant Pilot Drilling

Background/Objectives: This study investigates stress distribution in cancellous bone during pilot drilling for dental implants using the Cowper–Symonds model. Understanding the biomechanical effects of drilling parameters on bone health is essential for optimizing implant stability and longevity. Methods: A finite element analysis (FEA) approach was employed to simulate the pilot drilling process in cancellous bone. A three-dimensional jawbone model was developed from CT scan data, processed using 3D Slicer, and refined with CAD tools. The drilling simulation incorporated a rigid pilot drill and flexible cancellous bone, utilizing explicit dynamic methods. Stress distribution was evaluated for drilling depths ranging from 6 mm to 16 mm, with mesh density and strain rate effects considered to ensure accuracy. Results: The results showed an increase in stress levels with drilling depth, with maximum stress recorded at 16 mm. Initial contact stress was 17.3 MPa, rising to 228.9 MPa at deeper penetration due to increased interaction between the drill and bone. Stress distribution patterns emphasized the critical role of drilling depth and design parameters in mitigating bone damage. Conclusions: This study highlights the importance of optimized drilling protocols and pilot drill design to reduce stress and preserve bone integrity. The findings provide valuable insights into improving implant procedures and demonstrate the utility of FEA as a robust tool for evaluating biomechanical impacts during implant placement. Future research should incorporate cortical bone and thermal effects for a comprehensive analysis.

Influence of Material Properties on the Durability of Automotive Hydraulic Brake Discs: A Finite Element Analysis Approach

Influence of Material Properties on the Durability of Automotive Hydraulic Brake Discs: A Finite Element Analysis Approach

Finite Element Analysis of Layered Hollow Tapered Roller Bearings: Identifying Optimal Hollowness for Stress Reduction

Abstract Tapered roller bearings with hollow rollers offer advantages such as improved roller stiffness, enhanced speeds, and lower running temperatures due to better lubrication. Designing precise tapered roller bearings with hollow rollers is crucial. This study introduces a novel design of a layered hollow roller element aimed at minimizing contact pressure and stresses within the bearing, using a finite element analysis (FEA) approach. The study successfully employs elastic finite element analysis to determine the optimal hollowness level for the proposed design. The investigation covers hollowness levels from 30% to 80% for the rollers. The minimum contact pressure and Von-Mises stress were found to be 492.63 N/mm2 and 710.63 N/mm2, respectively. Results indicate that the optimal hollowness, yielding minimum stresses and contact pressure, is at 36%. These design modifications have potential applications in manufacturing industries where bearings are extensively used.

Experimental and numerical study on the residual seismic performance of post-blast RC piers

Aiming to evaluate the serviceability performance of bridge piers after potential terrorist attacks or accidental explosions, the residual seismic performance of post-blast reinforced concrete (RC) piers was studied by performing the test and numerical simulation. Firstly, the field explosion and successive lateral cyclic loading tests were performed on two 1/2-scale RC piers, and a single lateral cyclic loading test was performed on two intact control piers for comparison. The test data such as the incident overpressure-time histories, as well as the damage profiles, hysteretic curves and skeleton curves of piers, etc. were obtained and fully discussed. Then, an integrated finite element (FE) analysis approach based on the explicit–implicit switching algorithm was proposed to reproduce the dynamic and quasi-static responses of RC piers under blast and successive lateral cyclic loadings. Furthermore, four commonly used concrete material models were systematically compared and evaluated based on the basic mechanical property, explosion, and lateral cyclic loading tests. Finally, by comparing with the test data, the applicability of concrete material models and corresponding parameters, as well as the proposed integrated FE analysis approach for the residual seismic performance analysis of post-blast RC piers were verified comprehensively. It is concluded that: (i) after 0.5 kg TNT explosion, the positive yield and peak forces obtained from the lateral cyclic loading test are close to those of the intact control piers, whereas the negative yield and peak forces decrease to 66 % and 70 % of the intact ones; (ii) after 1.0 kg TNT explosion, the positive yield and peak forces are 77 % and 81 % of the intact values, while the negative yield and peak forces are only 37 % and 42 % of the intact ones; (iii) by replacing the explicit algorithm with implicit algorithm during the residual seismic performance analysis, the computational cost is saved by about 70 times; (iv) Winfrith concrete model can better predict the residual seismic performance of post-blast RC piers, with the deviations limited in 20 %. The present work can provide a reference for the designer and researchers in evaluating the seismic performance of the post-blast RC bridge piers during the whole service life.

Biomechanical Evaluation of a Novel Ceramic Implant for Canine Cranial Cruciate Ligament Rupture Treatment: A Finite Element Analysis Approach.

This research investigates the biomechanical effects of a novel ceramic implant for the treatment of canine cranial cruciate ligament rupture (CCLR) based on the tibial tuberosity advancement (TTA) method using finite element analysis (FEA). A 3D FEA of the tibiofemoral joint simulating the applied forces (44.5% of body weight) during the mid-stance phase (joint angle 135°) of the dog's stride was performed. Three conditions were considered for each joint: the physiological condition, the pathological condition with CCLR and the restored condition after TTA. Eight cadavers were used to create fifteen paired knee joints. The results showed significant differences in the forces that could be measured in the patellar tendon (PT) and in the cranial displacement of the tibial tuberosity between the conditions. The PT forces increased in the pathological state and continued to increase in the restored state, while the cranial displacement of the tibial tuberosity increased in the pathological state and decreased again in the restored state. Correlation analyses revealed significant correlations between PT forces, body weight and cranial displacement. The FEA provides initial insights into the force distribution and functionality of the ceramic implant. However, further testing is required to validate reliability and evaluate the efficacy of the implant.

Investigation of individual lack-of-fusion defects in the fatigue performance of laser-powder bed fusion Ti6Al4V alloys: A finite element analysis

Laser-Powder Bed Fusion (L-PBF) techniques have revolutionized the production of Ti6Al4V alloys across various industries. However, the widespread adoption of L-PBF Ti6Al4V alloys is impeded by their inadequate fatigue performance, particularly in high cycle regimes. A significant contributing factor to this limitation is the presence of internal defects inherent to the L-PBF process, act as sites for fatigue crack initiation. Previous investigations have focused on the fatigue performance of L-PBF Ti6Al4V alloys with gas porosities, while research on lack-of-fusions (LOFs) which are recognized as the most detrimental defects, remains limited. In order to deepen our understanding of the factors influencing the reduced fatigue performance observed in L-PBF Ti6Al4V alloys associated with inherent LOFs, this study employed three-dimensional (3D) finite element analysis approaches. Such approaches allow to assess fatigue indicator parameters to evaluate fatigue life and predict fatigue crack propagation. A 3D average Smith-Watson-Topper method has been proposed, which is able to rationally estimate the fatigue life of L-PBF Ti6Al4V. In addition, a novel finite element method has been developed to accurately calculate stress intensity factors along irregular shaped crack front of a notch-like feature embedded on a LOF. Additionally, parametric studies were conducted to gain further insights into the influence of LOFs on fatigue performance. The results shown the presence of embedded humps and notch-like features, and their topologies play key roles in the fatigue performance of LOF predominated L-PBF Ti6Al4V alloys.

Finite element analysis of crack propagation, crack-gap-filling, and recovery behavior of mechanical properties in oxidation-induced self-healing ceramics

The oxidation-induced self-healing of cracks is an attractive function for the application of ceramics in high-temperature structural components requiring high reliability. To further optimize materials or components for practical applications, the development of numerical simulation techniques is of importance. In this study, we examined crack growth, crack-gap-filling by oxide, and re-cracking behaviors in chevron-notched specimens under various load and temperature conditions by adopting a finite element analysis (FEA) approach incorporating a damage-healing constitutive model based on fracture mechanics and oxidation kinetics. Furthermore, by implementing the mechanical properties and oxidation kinetic parameters of reported self-healing ceramics composites into the FEA, we examined the effects of the composition and composite structure on the cracking and healing behaviors. Crack-gap-filling simulations suggested that the damage variables gradually decreased from the crack tip, and the minimum healing time was determined by the time required for the complete filling of the element at the crack mouth with the largest crack opening width. Furthermore, the recovery of the stiffness and strength could be successfully reproduced after complete healing with a reasonable healing temperature and time. The proposed FEA approach could also contribute to estimating the minimum healing time required at various temperatures to heal a given damage for various composites.

Impact force-damage depth model for ship-bridge collision

The impact force-damage depth model, i.e., P-a model, provides a feasible approach to design and evaluate bridge resistance under ship collisions, which is inadequately addressed in the existing specifications and literature. In the present study, based on an 18500 DWT (deadweight tonnage) bulbous bow bulk carrier and the main tower of cable-stayed bridges, the P-a model for ship-bridge collision is established with consideration of pile cap, bridge pylon and striking ship. Firstly, the refined finite element (FE) model of prototype ship was established with detailed modeling of both the main and stiffening components. The material model parameters and FE analysis approach were validated through the existing tensile tests on marine steel coupons and crush tests on ship bow specimens. It is found that the modeling of stiffening components has rationality in predicting the impact force and asymmetrical folding collapse of ship bow. Then, concerning two collision scenarios with the main tower of cable-stayed bridges, i.e., only bulbous bow-pile cap collision and sequential bulbous bow-pile cap and bow overhang-bridge pylon collisions, the influences of nine critical parameters from pile cap (height, curvature and water level), bridge pylon (width, curvature, angle and bow overhang-bridge pylon distance) and striking ship (mass and velocity) on the impact forces and failure patterns of ship bow were comprehensively discussed. It indicates that: (i) the larger impact forces of bulbous bow and bow overhang appear with increased pile cap height, decreased bridge pylon curvature and inward inclined pylon angle; (ii) the loading paths of P-a relationships are approximately identical with different striking ship masses and velocities. Finally, the P-a model for ship-bridge collision was established by response surface methodology, and the corresponding calculation procedure was further given and validated.

Influence of printing orientation on power-law hardening and ductile damage parameters for 3D-printed SS316L steel: experimental and FEA approach

In the present investigation, the selective laser melting (SLM) technique has been utilized for the 3-dimensional printing (tensile test specimens) of SS316L steel powder at 00 (horizontal) and 900 (vertical) angles. Further, an experimental and finite element analysis approach has been made to analyse the effect of printed orientation or direction on the Hollomon power law parameters (strain hardening exponent (n) and strength coefficient (K)) and ductile damage parameters (fracture strain (εf), stress triaxiality (η) and strain rate ( ε ̇ )). The influence of printing orientation on plastic deformation behavior has also been analysed. The results revealed that 00 angle 3D-printed specimens exhibited 11.05%, 21.97% and 9.50% more yield strength, tensile strength and elongation than 900 angle 3D-printed tensile test specimens. Further, the strain hardening exponent (n) and strength coefficient (K) (Hollomon power law hardening model parameters) for 00 angle 3D-printed specimens are 35.80% and 32.47% more than the 900 angle 3D-printed tensile test specimens respectively. The fracture strain for 00 angle 3D-printed specimens is 37.82% less than the 900 angle 3D-printed tensile test specimens. The percentage difference between FEA and experimental results is less than 5% which shows the good prediction capability of estimated Hollomon power law parameters and ductile damage model parameters with developed FEA model for 00 and 900 3D printed specimens.

Design and validation of a DMA-inspired device for in-vivo measurement of human skin mechanics: a finite element analysis approach

Abstract This study introduces a novel method for measuring the mechanical properties of human skin in-vivo, inspired by dynamic mechanical analysis (DMA). We designed and applied a DMA-like device to living human skin and validated its functionality through finite element analysis (FEA) on an ideally elastic skin model. The device features multiple testing modes, including horizontal movement in both same and opposite directions with optional pre-stretching. Stress-strain behaviours obtained from FEA align with initial setup parameters, serving as powerful tools for further research into the mechanical properties of skin. This method is expected to have potential significance in biomechanical theory, clinical, and healthcare applications.

Efficient power factor correction in single phase AC–DC boost converter for retrofitted electric bicycle battery charging: A finite element analysis approach

This research paper describes modifying a conventional bicycle into an electric bike by retrofitting it with a single-phase boost power factor correction (PFC) rectifier for low power battery chargers. The proposed work was designed and developed in a single stage, as opposed to the traditional two-stage chargers used to charge E-bicycle, to provide the desired outcomes of enhanced efficiency, good power quality, and dependability due to the charger's lower cost. Additionally, the proposed converter uses a single switch, which reduces not necessary body diode conduction and circulating current and enhances the PFC device's thermal management. Additionally, this research makes use of the diode bridge rectifier (DBR) arrangement, which offers low current stress and is suitable for electric bicycles. The converter operates at a low cost with reduced magnetics (DCM) by operating the charger in discontinuous conduction mode at such low voltage levels. It also accomplishes intrinsic power factor at the ac mains by employing a simple control method to maintain the battery in high power density constant current (CC) and constant voltage (CV) states. A thorough state space investigation is carried out in combination with modeling and testing to ensure that the electric bicycle charger operates effectively. Consequently, low power chargers are a good fit for the proposed single stage front-end converter, and a 250 W hardware prototype is used to verify the findings.

Preliminary Experimental and Numerical Study of the Tensile Behavior of a Composite Based on Sycamore Bark Fibers

In the context of global sustainable development, using natural fibers as reinforcement for composites have become increasingly attractive due to their lightweight, abundant availability, renewability, and comparable specific properties to conventional fibers. This paper investigates the tensile properties of a sycamore bark fiber-reinforced composite. The tensile tests using digital image correlation showed that, by adding 18% by volume of sycamore bark for the polyester matrix, the tensile modulus achieves 4788.4 ± 940.1 MPa. Moreover, the tensile strength of the polyester resin increased by approximately 90% when reinforced with sycamore bark fiber, achieving a tensile strength of 64.5 ± 13.4 MPa. These mechanical properties are determined by the way loads are transferred between the polyester matrix and fibers and by the strength of the bond between the fiber-matrix interfaces. Since it is difficult and time consuming to characterize the mechanical properties of natural fibers, an alternative approach was proposed in this study. The method consists of the identification of the fiber elastic modulus using a finite element analysis approach, based on tensile tests conducted on the sycamore bark fiber-reinforced composites. The model correctly describes the overall composite behavior, a good agreement is found between the experimental, and the finite element predicted stress–strain curves. The identified sycamore bark fiber elastic modulus is 17,763 ± 6051 MPa. These results show that sycamore bark fibers can be used as reinforcements to produce composite materials.

Integrated finite element analysis and machine learning approach for propagation pressure prediction in hybrid Steel-CFRP subsea pipelines

Accurate prediction of the propagation pressure (PP) in hybrid steel-CFRP pipe systems presents a substantial challenge due to intricate interactions and complex collapse failure modes. An efficient FE-based algorithm is programmed using ANSYS to numerically estimate the PP of hybrid steel-CFRP pipe, subjected to external pressure. This study employs a machine learning (ML) framework, addressing the inherent complexity with a three-phase approach: Parameter Design, Buckle Propagation Analysis, and ML Model Development. The dataset, encompassing about two thousand observations with four key features, undergoes k-fold cross-validation and min-max normalization for robust ML performance. Five ML models—Random Forest (RF), K-Nearest Neighbors (KNN), Genetic Programming (GP), Multi-layer Perceptron (MLP), and Support Vector Machine (SVM)—are developed and evaluated. The results revealed a significant influence of Ds/ts, a three-phase relationship with ts/tc, and a substantial decrease in PPh/PPs with increasing σys/σuc, predominantly exhibiting U-shaped or dog-bone failure modes in different scenarios. Proven that GP, KNN, and RF are the superior performers, ranking ahead of SVM with Gaussian Kernel (SVM-GK), MLP, and SVM with Linear Kernel (SVM-LK). Statistical metrics, Taylor Diagram analysis, and comparisons with FE results emphasize the effectiveness of GP, KNN, and RF. Additionally, normality tests and feature importance analysis provide nuanced insights.

Quantitative Analysis of the Hsu-Nielsen Source through Advanced Measurement and Simulation Techniques

Abstract This paper presents the results from conducting a series of experiments with a Hsu-Nielsen Source, accompanied by corresponding numerical simulations on a solid block. The aim being to illustrate a Finite Element Analysis (FEA) approach for simulating Acoustic Emission (AE) wave propagation in a Hsu-Nielsen Source, by employing virtual sensors to enhance existing AE research methodologies. The objective was to examine and establish the actual unload rate derived from Pencil Lead Breaks (PLBs) by comparing results from simulations and experimental trials. These experiments and simulations were conducted using a solid cylindrical steel block, capturing the propagating Acoustic AE waves from both sources over a two-second span. When comparing the experimental data with the simulation results, it is evident that replicating the structure of an impulsive AE source is feasible for brief durations. Furthermore, both the experimental and simulated signals on the steel cylinder displayed comparable patterns in the initial 25-30 µs. The methodology presented in this study demonstrates the effectiveness of Finite Element Analysis (FEA) in precisely identifying the specific modes present in AE wave propagation, including the actual unload rates affecting the AE signals recorded.

Optimizing Structural Integrity of Fighter Aircraft Wing Stations: a Finite Element Analysis Approach

Modern fighter aircraft are equipped with multiple stations on the fuselage and under the wings to accommodate various external stores, both jettisonable and non-jettisonable. Each configuration undergoes airworthiness certification, including structural analysis of individual stations within the carriage flight envelope. This study focuses on the structural analysis of a fighter aircraft wing station within this specified envelope. To perform this analysis, the wing station is extracted from the comprehensive global wing model, creating a sub-model with equivalent stiffness properties. Utilizing ANSYS Workbench®, Finite Element Analysis (FEA) is conducted for critical load cases to determine the Factor of Safety (FoS). The initial analysis reveals that the wing station has an FoS of 1.2 under the maximum design load. Prestressed modal and buckling analyses indicate a 10% increase in stiffness due to stress-stiffening effects. To further enhance load-carrying capacity, parametric design changes are introduced. Increasing the bolt diameter from 8 mm to 10 mm raises the FoS to 1.33, resulting in an 8% increase in the maximum load-carrying capacity of the wing station. This comprehensive approach, employing FEA, ensures the wing’s structural integrity under static load conditions within the carriage envelope. The study's findings support the wing station's enhanced performance and contribute to safer and more efficient aircraft operations.

Advancements in lightweight two-wheeler rim design: a finite element analysis approach with diverse materials

Advancements in lightweight two-wheeler rim design: a finite element analysis approach with diverse materials

Double-panel metamaterial with multi-resonator for broadband sound insulation

Currently, double-layer panels are usually filled with damping and sound-absorbing materials, which can effectively reduce the intensity of sound waves and enhance the sound insulation capability in the mid to low frequency range. Although this method can improve the peak and valley values in sound insulation to a certain extent, it still struggles to meet stricter design standards and requirements. This paper proposes a double-layer metamaterial plate with multi-resonator (DLMPMR) to fulfill sound insulation requirements through modifications to the double-layer plate structure. Firstly, the mathematical model pertaining to the sound insulation of DLMPMR is derived utilizing on the transfer matrix method and subsequently verified by the finite element analysis approach. Secondly, the influence mechanism of diverse structural parameters on the sound insulation performance of DLMPMR is studied. It is explored that the sound transmission loss (STL) of DLMPMR can be improved by adjusting the structural parameters to enhance the resonance of the structure across a broader frequency range and shifting the resonance frequencies to lower ranges. Finally, the sound insulation capability of the structure is verified through the reverberant fully anechoic chamber. The results demonstrate that the structure exhibits acoustic performance surpassing the mass law in the range of 220-5000 Hz. The proposed metamaterial, owing to the light weight and thinness, demonstrates promising potential for various applications in noise control engineering.

Dynamic behaviors of seismic-designed RC beams under asymmetrical low-velocity impact loads

Seismic-designed reinforced concrete (RC) structures could be subjected to asymmetrical low-velocity impact loads, e.g., vehicle/barge collisions and rockfall impacts, while existing studies mainly focus on the dynamic responses of symmetrical impacted scenarios. This study experimentally and numerically examined the influence of stirrup ratio and impact location on failure modes and impact behaviors of RC beams. Firstly, symmetrical and asymmetrical drop-weight tests were conducted on six RC beams, and digital image correlation technique was applied to capture the damage evolution process and dynamic responses. Then, the above test was reproduced to validate the applicability of the finite element analyses approach, and numerical simulations were further performed to explore the transformation mechanism of the failure mode of asymmetrical impacted beams. The results showed that, (i) the shear-bending capacity ratio of the beam decreased with the stirrup ratio increasing or the impact location moving towards the mid-span, causing its failure mode to transform from shear to flexural under asymmetrical impact loads; (ii) the shear bearing capacity mainly controlled the occurrence of concrete cracking of asymmetrical impacted beams, and moment bending capacity influenced the post-cracked performance; (iii) increasing the stirrup ratio improved the joint action between longitudinal bars and stirrups and enhance the confinement effect on concrete, reducing the damage degree and deformation of asymmetrical impacted beam; (iv) under the effect of shear wave propagation, asymmetrical impacted beams completed the global impact process faster than symmetrical impacted ones. Finally, a two-degree-of freedom model was established to quickly calculate the displacement-time history at the impact location of asymmetrical impacted beams. The current work could provide a helpful reference for the impact-resistant design of RC structures against asymmetrical impact loads.

Performance improvement of set of worm gears used in soot blower through profile modification

The present design of a set of worm gears used in a soot blower produced by a certain manufacturer has an efficiency of 68.8%. A soot blower is one of the most critical components in industrial applications for removing the large amounts of soot generated by boilers and is required to be operational 24×7. The energy consumption of the soot blower depends on its working efficiency and ultimately the design of its set of worm gears. This paper focuses mainly on the design and analysis of available industrial worm-gear sets used in soot blowers. The theoretical, experimental, and finite-element analysis approaches are validated for the stability of the worm gear set under typical input conditions. This paper also describes an analytical design of experiments (DOE) approach to identify the most significant factor for performance (efficiency) improvement and suggests some design improvements for the worm gear set using the profile modification approach. These ensure the efficiency improvement of the current industrial design of the set of worm gears used in a soot blower. The analytical DOE approach helped identify that the number of worm wheel teeth (Z2) and gear module (m) are the two most significant factors affecting performance. Accordingly, based on the improved design, the final efficiency increased from 68.8% to 74.6% (∼8.5% increment), resulting in lower power consumption during industrial application.

Prediction of allowable compression load for notched composite laminates combining FEA simulation and machine learning

Determining the allowable compression load (ACL) of notched composite laminates (NCL) requires consideration of buckling, intra- and inter-laminar damage, which is a costly and repetitive task due to the high dimensional and nonlinear relation of ACL to the numerous design variables. In this work, a high-throughput finite element analysis (FEA) and machine learning (ML) combined approach is proposed to predict ACL of laminates. First, the high-throughput FEA model of NCL covering all of the design variables is generated, and the corresponding critical compression loads in terms of buckling, intra- and inter-laminar damage are obtained. Then, ML models are trained, with inputs being the design variables of NCL and outputs being the critical compression loads. ACL and initial failure mode are determined by the minimum compression load of the three failure modes. Moreover, transfer learning is introduced to laminates with new design variables of new ply number, notch shape and laminate type. By fine-tuning the pre-trained ML model using scarce new data, the fine-tuned models are suitable for new laminates. Consequently, ACL and initial failure mode of notched laminates with various design variables are predicted.