Finite Element Analysis Software Research Articles

Functional Load Capacity of Teeth with Reduced Periodontal Support: A Finite Element Analysis.

The purpose of this study was to investigate the functional load capacity of the periodontal ligament (PDL) in a full arch maxilla and mandible model using a numerical simulation. The goal was to determine the functional load pattern in multi- and single-rooted teeth with full and reduced periodontal support. CBCT data were used to create 3D models of a maxilla and mandible. The DICOM dataset was used to create a CAD model. For a precise description of the surfaces of each structure (enamel, dentin, cementum, pulp, PDL, gingiva, bone), each tooth was segmented separately, and the biomechanical characteristics were considered. Finite Element Analysis (FEA) software computed the biomechanical behavior of the stepwise increased force of 700 N in the cranial and 350 N in the ventral direction of the muscle approach of the masseter muscle. The periodontal attachment (cementum-PDL-bone contact) was subsequently reduced in 1 mm increments, and the simulation was repeated. Quantitative (pressure, tension, and deformation) and qualitative (color-coded images) data were recorded and descriptively analyzed. The teeth with the highest load capacities were the upper and lower molars (0.4-0.6 MPa), followed by the premolars (0.4-0.5 MPa) and canines (0.3-0.4 MPa) when vertically loaded. Qualitative data showed that the areas with the highest stress in the PDL were single-rooted teeth in the cervical and apical area and molars in the cervical and apical area in addition to the furcation roof. In both single- and multi-rooted teeth, the gradual reduction in bone levels caused an increase in the load on the remaining PDL. Cervical and apical areas, as well as the furcation roof, are the zones with the highest functional stress. The greater the bone loss, the higher the mechanical load on the residual periodontal supporting structures.

Numerical study on the design of flax/bamboo fiber reinforced hybrid composites under bending load

Natural fiber-based composites are essential for the environment in this era of depletion of petroleum resources and for new green environmental rules, as they have limited detrimental behavior or response against the environment. In this paper, firstly, the suitability of replacing glass fiber with natural bamboo fiber in a flax/glass/epoxy hybrid composite under a fixed bending load is investigated using Finite Element Analysis (FEA) software ABAQUS with proper model validation. Finally, five different lay-up sequences of flax/bamboo/epoxy hybrid composite laminate for fixed volume fractions of flax and bamboo strips are investigated numerically to develop design strategies for binary hybrid composite. It is found that the bending stiffness and equivalent modulus of elasticity for model FB-1 are increased by 37.53 % and 37.52 % respectively compared to the base model while the energy absorption for model FB-3 is highest which is 105.89 % higher than the base model. Analysis of various lay-up sequences showed that flexural behavior can be improved by fabricating binary hybrid composites using the concept of a sandwich structure. It is shown that all highly stiff laminas should be placed on the outer sides of the composite to achieve the maximum bending stiffness whereas they should be placed at the center to attain the maximum energy absorption.

Intensity analysis of frictional heat source during core tube sampling and drilling

AbstractCurrently, the heat generated during coal core tube sampling causes rapid gas desorption, leading to substantial measurement errors in laboratory gas content assessments. Reducing these errors requires studying frictional heat from core tube friction against the hole wall and coal core temperature rise. Combining the independently developed device to simulate the thermal effect of coring and the COMSOL finite element analysis software, the intensity of the frictional heat source during the core tube sampling and drilling process was analyzed under different coring depth and rotational speed conditions. The research results show that: At constant speed, frictional heat intensifies as the core depth increases. However, the rate of temperature rise decreases with increasing core depth; when the coring depth is constant, the frictional heat is proportional to the rotational speed. For example, at a depth of 140 m and a rotational speed of 120 r/min, the intensity of frictional heat generated by drilling is 2.21 ∗ 10E6J. Similarly, at 180 r/min, the strength is 2.28 ∗ 10E6J, and at 240 r/min, the strength reaches 3.65 ∗ 10E6J; Under certain conditions, core tube wall temperature will not rise indefinitely but will stabilize to a certain value.

Characteristics and Treatment Strategies for Basicervical and Transcervical Shear Fractures of the Femoral Neck.

This study aimed to define basicervical and transcervical shear fractures using area classification and to determine the optimal osteosynthesis implants for them. The clinical outcomes of 1042 proximal femur fractures were investigated. A model of the proximal femur of a healthy adult was created from computed tomography images, and basicervical and transcervical shear fractures were established in the model. Osteosynthesis models were created using a short femoral nail with a single lag screw or two lag screws and a long femoral nail with a single lag screw or two lag screws. The minimum principal strains of the fracture surfaces were compared when the maximum loads during walking were applied to these models using finite element analysis software. Basicervical fractures accounted for 0.96% of all proximal femur fractures, 67% of which were treated with osteosynthesis; the failure rate was 0%. Transcervical shear fractures accounted for 9.6% of all proximal femur fractures, 24% of which were treated with osteosynthesis; the failure rate was 13%. Finite element analysis showed that transcervical shear fracture has high instability. To perform osteosynthesis, multiple screw insertions into the femoral head and careful postoperative management are required; joint replacement should be considered to achieve early mobility.

Experimental study on fire resistance of high strength Q960 steel columns under axial compression

In order to obtain the mechanical behavior of H-shaped high-strength Q960 steel column under axial compression in fire, the bearing capacity tests of two Q960 steel columns at ambient temperature and fire resistance tests of six Q960 steel columns at elevated temperature were carried out. By considering different slenderness ratios, load ratios, and heating rates of the test columns, the furnace temperature, column temperature, lateral displacement, and axial displacement were measured and recorded. Then, critical temperature, fire resistance, and failure mode of the columns were obtained. The thermal-mechanical coupling analysis model for the Q960 steel column was established by using ABAQUS finite element analysis software. After verifying the accuracy of the model, parameter analysis was carried out to investigate the effects of load ratio, slenderness ratio, geometric imperfection, thermal creep, residual stress, and steel strength on the fire resistance of steel columns. Based on the test data and analysis results, a fire resistance design method for high-strength Q960 steel columns under axial compression is proposed.

Research on blasting mechanism and blasting effect of aqueous media in open pit coal mines

Surface coal mining procedures include piercing—blasting—mining and loading—transportation—discharging, blasting link exists due to the poor blasting effect leads to low loading efficiency, blasting dust caused by environmental pollution and other problems. In this paper, from the mechanical characteristics of the water medium, we analyze in detail the transferring effect, transducing effect and bubble pulsation phenomenon of the water medium in the blasting process. The results show that when the blasting medium is water medium, the maximum principal stress is 1.53 times that of air medium; the peak energy transfer can be up to 2.73 times that of air medium. With the help of TrueGrid/LS-DYNA finite element analysis software to simulate the dynamic process of blasting, the study of the maximum principal stresses around the hole, the top of the slope, the foot of the slope on the maximum principal stress changes, the results show that the maximum principal stresses around the hole, the top of the slope, the foot of the slope unit with the increase in the water content is gradually increasing trend. Finally, combined with the actual mine production conditions for blasting field test, water-mediated blasting dust reduction rate of 75%, the use of AHP—fuzzy comprehensive evaluation method of two groups of traditional dry hole blasting and three groups of water-mediated blasting comprehensive evaluation, the results show that the water-mediated blasting scores are higher than the traditional dry hole blasting, proving that the water-mediated blasting has a certain prospect of engineering applications.

Analysis of Group Pile Bearing Modes of Permeable Pile Dam with Different Incoming Flow Angles

Based on ABAQUS finite element analysis software, the group piles and single piles under different incoming flow angles are compared and calculated, the horizontal bearing characteristics of the group piles of permeable pile dam under different incoming flow angles are analyzed, the pile-soil force is solved, and the change rules of the load-displacement characteristics, the displacement distribution of the pile body, and the distribution of the pile body bending moment are analyzed in detail. The study shows that: for the group piles with flow angles of 0° and 45°, the stresses from the upstream piles to the downstream piles tend to increase along the flow direction, and a stress concentration occurs at the downstream pile; for the group piles with flow angles of 90°, the stresses gradually increase from the central pile to the piles on both sides, and the stress concentration area is distributed at the outermost pile. With the increase of the incoming flow angle, the horizontal bearing capacity of the whole group of piles shows an increasing trend, but due to the effect of the group piles, the bearing capacity of the unit piles is smaller than that of the single piles; The displacements of the group piles at different incoming flow angles were greater than those of the single piles, and the turning points were all at about 12 m below the mud surface; With the increase of incoming flow angle, the group pile starts to change from rigid deformation to flexible deformation, the maximum bending moment of the pile body decreases, and the maximum value of the bending moment of the pile body occurs at the burial depth of 5 m. The maximum value of the bending moment of the pile body decreases with the increase of incoming flow angle.

Anti-resonance fiber propagating 86 orbital angular momentum modes with high purity for a long distance

Future advances in information transmission technology require better capacities for fiber optics communication. As a new degree of freedom, the orbital angular momentum (OAM) has attracted extensive attention in the field of mode division multiplexing. Herein, an anti-resonance fiber (ARF) is designed with three different materials, SF11, LaSF09, and SiO2, for the negative curvature tube. Systematic analysis and optimization are carried out to determine the number of layers of the negative curvature tubes in the cladding, the number of second-layer cladding tubes, and thickness of the annular area. The finite element analysis software COMSOL is utilized to calculate the effective refractive index difference, dispersion, limiting loss, and other characteristics. The ARF can stably transmit 86 OAM modes in the wavelength range between 1.2 and 2.0[Formula: see text][Formula: see text]m, and the minimum refractive index difference is greater than [Formula: see text], which effectively reduces the mode abridgment. The nonlinear coefficients of the HE[Formula: see text] mode and the OAM purity of HE[Formula: see text] mode are 0.34[Formula: see text]km[Formula: see text][Formula: see text]⋅[Formula: see text]W[Formula: see text] and 99.43%, respectively, thus facilitating stable transmission of OAM modes for a long transmission distance. The anti-resonance fiber has significant application potential in long-distance network information transmission, relay communication, and other communication areas.

Energy-Dissipation Support Technology for Large Deformation Tunnels Based on the Post-Peak Behavior of Steel Plate Buckling: A Case Study

Large deformations can easily occur when tunneling through weak surrounding rock with high underground stresses. Under high-stress environments, the surrounding rock stores a large amount of strain energy, and the strain energy stored in the soft and weak surrounding rock enclosure is dissipated through the large traveling plastic deformation. Therefore, the effective use of the surrounding rock’s bearing capacity and energy dissipation is a feasible solution to the large deformation problem. Based on the energy principle, this study designs a high compressibility, large stroke energy-dissipation element, which transforms the traditional support into energy-dissipation support and solves the problem of large deformation by reasonably utilizing the “displacement” of the surrounding rock. The experimental results showed that the steel plate assembled structure had an initial peak value of about 15 MPa, a constant resistance of about 2 MPa with a large stroke, and a compression rate of more than 75%, with good post-compression flexural peak characteristics. Elastic–plastic buckling analyses of defective steel plate composite structures were carried out using finite element analysis software, and the deformation and force characteristics of a variety of steel plate composite structures after buckling under actual field conditions were investigated. Based on the 3D laser scanning system, the thickness of the upper and lower steel plates of the steel plate composite structure was set to 1 cm, the height of the vertical plate was set to 28 cm, and the thickness was set to 8 mm. The original rigid supporting method was converted into one of compression support by circumferentially embedding the steel plate composite structure into the initial support structure. The resulting support configuration offered a high safety factor because the pressure of the surrounding rock was released by the deformation of the steel plate composite structure.

Dislocation density-based modeling of the yield drop phenomenon in nickel-based single crystal superalloy

The phenomenon of yield drop, characterized by a decrease in flow stress after initial yield, has been observed in various nickel-based superalloys. Despite numerous proposed physical mechanisms, there is still a lack of a meso-mechanism-based constitutive model to explain this phenomenon. In this study, the tensile behavior of a nickel-based single crystal superalloy (DDX), was investigated at different strain rates and a temperature of 900 °C. It was observed that the yield drop phenomenon in DDX became more pronounced with increasing strain rate. To predict the yield drop phenomenon during tensile processing, an improved strength law based on continuum dislocation density theory was considered in the crystal plasticity framework. The proposed constitutive model was implemented using nonlinear iteration and incorporated into a finite element analysis software. The simulation results exhibited a good agreement between the experimental data and the stress–strain curve in the vicinity of the yield drop region, affirming the predictive aptitude of the proposed model in elucidating the yield drop phenomenon at various strain rates.

Finite element analysis comparison of Type 42A2 fracture fixed with external titanium alloy locking plate and traditional external fixation frame

BackgroundAt present, not all Type AO/OTA 42A2 open fractures can be treated by external fixation brackets, not to mention the inconvenience of this technique in clinical practice. External titanium alloy locking plates, which are lightweight and easy-to-operate, can be used as an alternative treatment option for such patients. However, there are few reports of finite element biomechanical analysis on the titanium alloy locking plates and fixation brackets being placed on the medial side of the tibial fracture. In this study, the biomechanical properties of titanium alloy locking plates and fixation brackets for treating Type AO/OTA 42A2 fractures were compared by applying the finite element method, and the results provided data support for the clinical application of the external titanium alloy locking plate technique.MethodsType AO/OTA 42A2 fracture models were constructed using CT data of a male volunteer for two external fixation techniques, namely the external titanium alloy locking plate technique and the external fixation bracket technique, according to commonly-used clinical protocols. Then, the four-point bending, axial compression, clockwise rotation and counterclockwise rotation tests under the maximum load were simulated in finite element analysis software. The stress distribution, peak stress and overall tibial displacement data for the two different external fixation techniques were obtained and compared.ResultsIn the four different test conditions (i.e., four-point bending, axial compression, clockwise torsion, counterclockwise torsion) under the maximum load, the two external fixation techniques showed obvious von Mises stress concentration at the contacts between the screw and tibia, between the screw and titanium alloy locking plate, between the self-tapping self-drilling needle and tibia, between the self-tapping self-drilling needle and the external fixation device, as well as around the fracture end and around the cortical bone at the upper and lower ends of the tibia. The peak stress was ranged 26.67–558.77 MPa, all below the yield stress strength of titanium alloy. The peak tibial displacement of the external titanium alloy locking plate model was smaller than that of the fixation bracket model. In terms of structural stability, the external titanium alloy locking plate technique was superior to the external fixation bracket technique.ConclusionsWhen fixing Type AO/OTA 42A2 fractures, external titanium alloy locking plates are not only lightweight and easy-to-operate, but also have better performance in terms of axial compression, bending and torsion resistance. According to the finite element biomechanical analysis, external titanium alloy locking plates are superior to traditional external fixation brackets in treating Type AO/OTA 42A2 fractures and can better meet the needs of clinical application.

One-Way Fluid Structure Interaction of a Utility Vehicle Splitter using CFD Modelling

The Utility Vehicle, commonly known as a “ute” in New Zealand, and a “pickup” in other countries, is very popular for work, recreation and motorsport. This report investigates how the addition of a front splitter influences the handling ability on a Ford Courier Ute, for better aerodynamics during racing. Computational fluid dynamics (CFD) methods and Finite Element Analysis (FEA) were used to investigate the one-way fluid structure interaction of the speed of the Ute with and without the splitter modification. Three configurations of the splitter were modelled and analysed using SolidWorks 2022, CFD and FEA packages. The ground clearance between the splitter and the road was set at three heights, 200 mm, 150 mm and 50 mm. These designs were compared with the control, in terms of the amount of downforce, drag and aerodynamic efficiency. The ground clearance of 150 mm was optimal, in terms of the parameters investigated. The findings from this paper may inspire Ute enthusiasts to fit a splitter to their Ute for racing applications.

Development of a low-frequency accelerometer based on symmetric multi-stage triangular beam fiber Bragg grating

In order to meet the needs of accelerometers for low-frequency seismic exploration, a fiber-optic grating accelerometer based on a symmetric multi-stage triangular hinge is proposed. The sensitivity of the accelerometer is improved by the symmetrical multi-stage triangular beam structure, and experimental verification is carried out. The resonant frequency and sensitivity equations of the accelerometer are given based on theoretical analysis, while the finite element analysis software is used to simulate and analyze the characteristics of the accelerometer such as resonant frequency, stress distribution, and amplitude-frequency response. The structural parameters of the accelerometer are optimized by numerical analysis software, and the influence of the structural parameters on the sensitivity and resonant frequency of the accelerometer is analyzed. The experimental results show that the accelerometer has a resonant frequency of 140 Hz and a linearity of 99.9 % in the flat region of 1–70 Hz, a sensitivity of 337.325 pm/g, and an interference immunity of 5.39 % in the lateral direction in the working axis direction. This indicates that the accelerometer shows good linearity and lateral interference immunity in the flat interval, which well meets the needs of seismic wave signal monitoring in the field of low-frequency oil and gas exploration.

Simulation of, Optimization of, and Experimentation with Small Heat Pipes Produced Using Selective Laser Melting Technology

With the development of microsatellite technology, the heat generated by onboard components is increasing, leading to a growing demand for improved thermal dissipation in small satellites. Metal powder additive manufacturing technology offers the possibility of customizing and miniaturizing heat pipes to meet the specific requirements of small satellites. This article introduces a small-scale heat pipe designed using selective laser melting (SLM) technology. The heat pipe’s material, structure, and internal working fluid were determined based on mission requirements. Subsequently, the SolidWorks 2021 software was used for heat pipe modeling, and the ANSYS 2021R2 finite element analysis software was employed to simulate the heat transfer performance of the designed heat pipe, confirming its feasibility. The heat pipe’s structure was optimized using multi-objective regression analysis, considering various structural parameters, such as the channel diameter, vapor chamber height, and narrow gap width. The simulation results demonstrate that the optimized heat pipe achieved a 10.5% reduction in thermal resistance and an 11.6% increase in equivalent thermal conductivity compared to the original heat pipe. Furthermore, compared to conventional metal heat-conducting rods, the optimized heat pipe showed a 38.5% decrease in thermal resistance and a 62.19% increase in equivalent thermal conductivity. The heat pipe was then fabricated using a 3D printer (EOS M280), and a vacuum experimental system was established to investigate its heat transfer characteristics. The experimental results show that the heat pipe operated most efficiently at a heating power of 20 W, reached its maximum heat transfer capacity at 22 W, and had an optimal fill ratio of 30%. These results highlight the excellent performance of the heat pipe and the promising application prospects for SLM technology in the field of small satellites.

The Seismic Behavior of Buildings with Flat Slab Systems under Near-Fault Ground Motions

It is well known that structural displacement or ductility demands of structures subjected to near-fault ground motions are generally greater than ordinary ground motions. Therefore, the effect of earthquake records in the near region on the seismic behavior of structures has been widely studied in the last decades. Peak ground acceleration (PGA) is an important key parameter, which determines structural behavior. However, structural behavior depends on the distance of the structure to the fault zone, the ratio of peak ground velocity (PGV) to peak ground acceleration, the velocity pulse duration of ground motion, and the natural period of the structure. In this study, the seismic behavior of buildings with flat slab systems was investigated under near-fault ground motions. Linear time history analysis was performed for a 30-storey building designed according to TBEC-2018 using SAP 2000 finite element analysis software. Results were compared with the behavior of the building with a solid slab system. It is concluded that the ratio of PGV/PGA is very effective on the flat slab systems.

FFEA software: Repeated early innovation

FFEA software: Repeated early innovation Dr Joanna Leng, Senior Research Software Engineering Fellow at the University of Leeds, discusses software with repeated early innovation using the example of the FFEA software. This article analyses the application of software engineering (SE) tools and practices and research software engineering (RSE) practices to the Fluctuating Finite Element Analysis (FFEA) software, a mesoscale modelling package. In 2016, I met the FFEA team to discuss improving their software. In 2020, I started working with them to develop a roadmap for the FFEA software by assessing their research interests and software.

Analysis of sealing performance of combined seal structure with metal C-ring with built-in spring

The built-in spring reinforced metal C-shaped sealing ring is a high-performance static sealing component. Its metal combination sealing structure is designed to meet the sealing requirements of all metal graded cementing tools. To analyze and study the sealing performance of this combination sealing structure under complex underground application conditions, a three-dimensional simulation analysis model of the metal C-shaped ring combination sealing structure was established using ANSYS finite element analysis software, Simulate and analyze the stress and deformation of the combined sealing structure under different working conditions (room temperature and high temperature), and discuss the influence of external load conditions, including underground working medium pressure, temperature, and pre compression amount, on the sealing performance of the combined sealing structure. Calculate the variation law of contact pressure and equivalent stress under specific external conditions, providing some reference basis for the design and application of sealing rings and combined sealing structures.

Study on mechanical properties of wind turbine tower reinforced by ribbed interlayer

In order to avoid the economic loss caused by the demolition and reconstruction of old steel wind turbine towers and to meet the demand of new generating units for tower strength and stiffness, this paper proposes a laminated ribbed structure for strengthening old wind turbine towers based on the concept of hollow laminated steel pipe concrete. The four interlayer ribbed reinforced cylinder specimens were made of two steel cylinders, both round and concentric, with vertical stiffening ribs evenly arranged on the inner surface of the outer cylinder and the outer surface of the inner cylinder, and concrete was poured between the two cylinders. The number of cavities, concrete thickness and shear-to-span ratio were used as the test parameters to conduct compression-bending tests on five specimens. The test results show that: the damage phenomenon of the specimen is obvious, the material performance of each component is fully played, and the stiffening ribs can effectively alleviate the local bulging of the specimen; in terms of ultimate bearing capacity, the most influential is the shear-to-span ratio, the smaller the shear-to-span ratio, the larger the ultimate bearing capacity, increasing the concrete thickness and the number of cavities can effectively improve the ultimate bearing capacity; in terms of initial stiffness and ductility, the increase of the number of cavities will significantly improve the initial stiffness and ductility of the specimen. In terms of initial stiffness and ductility, increasing the number of cavities will significantly improve the initial stiffness and ductility of the specimen. The reinforcement effect of sandwich layer with ribbed structure on the tower structure is remarkable. The finite element analysis software ABAQUS was used to establish a model consistent with the test, and the calculation results were compared with the test results to verify the feasibility and accuracy of the established model and the material intrinsic structure relationship. On this basis, typical members are selected, and the stresses and plastic strains are combined with the longitudinal stresses and plastic strains to analyze the whole process of the stresses in the reinforced barrel of the sandwich ribbed structure in depth. The research results provide the theoretical basis and experimental basis for wind turbine tower reinforcement.

Stability Analysis of a Transmission Line Tower and Slope under Heavy Rainfall

In recent years, our country’s transmission lines have often been in danger due to geological disasters such as landslides when passing through fragile geological environments, which has brought great challenges and risks to the operation and maintenance of transmission lines. In order to understand the impact of transmission line towers on tower foundation slopes under heavy rainfall conditions, the influence of towers at different locations, rainfall intensities, and slopes on slope stability was analyzed by using Geo-Studio finite element analysis software. The results show that the slope has an important influence on the selection of the reasonable position of the tower. When the tower is located at the lower part of the slope, the safety factor of the slope is the highest. The safety factor of the slope is also reduced, and eventually the slope will be unstable and destroyed; the stability coefficient of the slope in the natural state is 1.221, which is in a stable state. Slopes are prone to overall sliding, with the spoil and overburden as the sliding body and the rock–soil contact surface as the sliding surface. This result provides a scientific basis for further understanding the influence mechanism of the slope angle at the location of the tower pole on this type of landslide under rainfall conditions. Further research can use the results of this paper as a benchmark to carry out corresponding experimental analysis and verification work.

Finite Element Modelling of the Effect of Adhesive Z-Connections on the Swelling of a Laminated Wood Composite

This study used finite element analysis (FEA) to model the effects of adhesive Z-connections on the thickness swelling of laminated wood composites exposed to water. We hypothesized that the area density, diameter, and spatial distribution of adhesive Z-connections will influence the ability of Z-connections to restrain thickness swelling of the composites. We tested this hypothesis by modelling a wood composite in ANSYS FEA software v. 17.0 to explore the effect of moisture on the thickness swelling of the wood composite. The results were compared with those obtained experimentally. We then examined the effect of the area density, size (diam.), and spatial distribution of the adhesive Z-connections on the thickness swelling of wood composites. Our results showed a positive correlation between the number of adhesive Z-connections in the composites and restriction of thickness swelling following 72 h of simulated moisture diffusion. Similarly, increasing the size of adhesive Z-connections also restricted thickness swelling. In contrast, different spatial distributions of Z-connections had little effect on restraining thickness swelling. Our modelling approach opens up opportunities for more complex designs of adhesive Z-connections, and also to examine the effect of wood properties, such as permeability, density, and hygroscopic swelling ratios on the thickness swelling of laminated wood composites.