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The paper presents the finite element modeling of the spatial heat transfer to identify the temperature and the heat flux distributions both in the linear and point thermal bridges in various up-to-date wall systems. The paper considers the spatial heat transfer in the corner zone of the brickwork fragment. The ANSYS finite element program is used for the numerical simulation of the temperature fields and thermal fluxes for the brickwork connection with a hollow-core slab and a balcony slab. The influence of hollow cores in the floor slab is considered in relation to the temperature behavior along the inner surface of the brickwork fragment. To eliminate the negative effect from thermal bridging, it is suggested to increase the temperature on this inner surface. The brickwork thermal properties are investigated herein. [ABSTRACT FROM AUTHOR]

Recently, the technology of construction of underground parts of buildings and "top-down" structures has become more and more popular. The effectiveness of this technology has been noted by many authors. Underground fencing and spacer elements of the structure perceive significant loads not only during the exploitation period, but also during the construction of all levels of the underground part. When designing, it is necessary to take into account the change in the stress-strain state of the fastening of the walls of a deep pit. This paper presents the results of researching of changes in the stress-strain state of anchoring the walls of a deep foundation pit by the "wall in the soil" method in the numerical modeling of floor excavation using the "top-down" technology. A volumetric finite element model of the underground part has been developed, which provides for sequential excavation to a depth of one floor with an estimate of the SSS parameters at each stage of the work. [ABSTRACT FROM AUTHOR]

Brake system is most essential and critical component in automobiles. The braking system mainly comprises a brake plate, brake shoes and brake drum. Principle of working braking system is combination of shoe and brake actuating mechanism. This brake mechanism converts kinetic energy into heat energy, to retard the vehicle movement by means of friction. Brakes should have enough strength with minimum weight and also consider optimum value of heat rate. In this paper first part is dynamic analysis of brake drum with finite element method, and then next is transient analysis of finned brake drum and effectiveness of the heat transfer rate for the different materials used for brake drum. The materials considered for brake drum is EN AC-41700 Cast Aluminum; finally comparing the heat flux of the original brake drum, five-finned brake drum and seven-finned brake drum. [ABSTRACT FROM AUTHOR]

A Spur gear drive is a mechanical drive which transmits power through toothed wheels between two parallel shafts. Spur gear teethes are parallel to the axis of the shaft, due to which while transmitting the power high impact load is acting on the gear teeth repeatedly. Fatigue analysis of spur gear drive is very important to understand the effect of repeatedly acting impact loads. In this paper, vibration fatigue analysis of two different spur gear drives with different power outputs has been performed. Spur gear drive systems are designed according to Hertz and Belayev gear design approach and finite element model is developed in ANSYS 18.1. Frequency domain approach is implemented in vibration fatigue analysis for the estimation of fatigue life by using Steinberg's three band theory and Miner's cumulative damage theory. During the vibration fatigue analysis of the systems, a constant damping ratio was used. Spur gear drive system is subjected to random loading and power spectral density is implemented for estimating the mean stresses developed in the system. Fatigue life estimation of the spur gear drive system is done for different materials: Structural steel, C45 cast steel, woven carbon epoxy prepreg and compared their fatigue life. It has been observed that C45 cast steel is the best material irrespective of the power output of the spur gear drive system. It has also been noted that for high power gear drive applications, woven carbon epoxy prepreg is more suitable than structural steel and C45 cast steel. [ABSTRACT FROM AUTHOR]

Assumptions and simplifications in finite element (FE) modelling for structural vibration analysis contribute to discrepancies in numerical results. This paper presents FE model updating on components of a simplified model of an aircraft pylon. The components are tested under free-free boundary conditions. Impact testing is performed with roving accelerometers technique. Modal parameters are predicted numerically using NASTRAN SOL 103 normal modes analysis. NASTRAN SOL 200 optimisation for modal based updating method is subsequently used and successfully minimised the total error of the initial FE model from 19.17 per cent to 3.19 per cent. These satisfactory results could be confidently enhanced the quality of the FE model to be used for the further engineering analysis. [ABSTRACT FROM AUTHOR]

The laser spot weld is widely used to join automotive structural components due to the advantages of being inexpensive and more efficient. However, developing a reliable FE model of a laser spot weld for investigating a structure's modal parameters is very challenging. A repeated assessment of the welded joint model can significantly affect the efficiency of the finite element method, especially for a large complex structure that usually consists of huge numbers of degrees of freedom. This paper presents a wave-based substructuring method to speed up a modal parameters analysis of a laser spot welded structure. A reduced model is developed based on the wave-based substructuring scheme and compared with the full finite element model in computational time and accuracy. It was found that the proposed scheme was able to reduce the computational time of a modal parameters analysis significantly. The proposed scheme may provide advantages for research requiring high computational analysis. [ABSTRACT FROM AUTHOR]

This paper focusing on the joint modelling techniques of Finite Element (FE) to model a light dissimilar structure with bolted joints made up of bolts and nuts. The usage of a model update strategy is employed to improve the FE model's dynamic behaviour. In the FE model, a joint strategy is constructed using three different types of element connectors: CBAR, CBEAM, and CFAST. The modal parameters of a bolted joint structure made of dissimilar materials AZ31B and AA6061 were determined using Finite Element Analysis (FEA) and Experimental Modal Analysis (EMA) in this research (natural frequencies, damping ratio, and mode shapes). The number of elements, number of nodes, and total percentage errors of respectively initial FE model, when compared to EMA results, were evaluated. In comparison to the others, the CBAR element was chosen to represent a fastener joint for the updating process due to its accurate prediction of mode shapes and inclusion of updating parameters. Sensitivity analysis is performed before the updating process to choose the most sensitive parameter for updating purposes. In the FE model updating procedure, MSC Nastran's optimization technique is applied. Therefore, the discrepancies between FEA and EMA have been decreased. When compared to the measured equivalent, the percentage of error for the modified CBAR model drops from 4.37 percent to 2.71 percent. As a result, it is discovered that updating the FE model is a systemic and efficient technique in conducting the appropriate FE model in recreating the genuine structure. [ABSTRACT FROM AUTHOR]

This paper would focus on the structure of aluminium alloy spot welded crash box with the trigger mechanism as the structure are widely studied for its crashworthiness as well as the location of the structure itself at the car chassis which are subjected to dynamic loading of the car. Aluminium alloy is broadly used in the car body-in-white due to the properties of sufficient strength, better formability, light weight as well as good crashworthiness properties while welded joints are also extensively used as a joining of car components. As this study use both approach of finite element and experimental, in order to validate the finite element analysis (FEA) data, it would be correlated with the experimental approach and further optimization of the finite element (FE) modelling would be made to reduce the discrepancies of data. In this study, the model updating method which update the most sensitive modal parameters would be used towards the crashworthiness analysis to observe for any significant difference with the initial crashworthiness analysis. Finite element modal analysis would be done for the crash box structure and the data would then be correlated with experiment modal analysis (EMA). The same finite element modelling would also be used for the finite element crashworthiness analysis. For modal analysis of both approach, model updating was done to reduce the discrepancies and the sensitive modal parameters were identified and it were used in the new crashworthiness analysis. From the study, it could be observed that the crashworthiness output of the crash box structure with the updated model were different from the initial crashworthiness output in term of its total energy absorbed. [ABSTRACT FROM AUTHOR]

This paper study deals with selection of different material used for construction of Liquified Petroleum Gas cylinder which is used in our day-to-day life. Solidwork-2020 is used for modelling of LPG Cylinder. finite element analysis (FEA) of LPG cylinders made of Low carbon Steel and E-Glass Epoxy composites has been carried out. They are subjected to internal pressure. ANSYS (version 2021) has been used to Analyze the LPG cylinder. Both Static structural Analysis and Dynamic analysis is done. The Ansys results of deformation and stresses for Low Carbon steel & composite cylinders are compared which are built of Low carbon steel (LCS) and E-Glass Epoxy are studied. [ABSTRACT FROM AUTHOR]

Numerous empirical and numerical studies have been carried out on the mechanical characterization of ductile materials. The application of digital image correlation (DIC) equipped with three-dimensional measurement analysis was used to examine the mechanical characteristics of aluminum alloy (AL 7075). Then, the DIC outcome with finite element simulation results will be compared with the experimental results to measure the performance of the DIC. A tensile specimen of AL 7075 is tested under constant loading with a 2 mm/min displacement rate until fracture. Strain gauge and extensometer are used along with DIC monitoring technique to capture the structural deformation of the specimens. The specimen and test are simulated in ABAQUS software, in which the results are compared with experiment and DIC data, indicating a good correlation between the results. Limited data in the form of average deformation and strain of the experiments are not applicable to the plastic and necking process. In this respect, the 3D DIC results are used to analyze the strain field throughout the test, including specimen necking, and predict fracture location. Moreover, the outcome of DIC and finite element simulation are employed to examine the characteristics of AL 7075 about the large plastic deformation and mechanical behavior. The proposed 3D DIC methodology in providing insight into the characteristic mechanical behavior of ductile materials is highlighted in this paper. [ABSTRACT FROM AUTHOR]

This paper addresses the problem of natural convection in H-Form cavity with differentially heated side walls having two circular adiabatic obstacles. To achieve accurate solutions of the equations system defining this study, the computational methods are founded on the finite element method (FEM). Numerical illustrations have been carried out and discussed for several Rayleigh numbers from 10 to 106. We show the impact of Rayleigh number as a crucial parameter on both the heat transfer and the fluid flow. We deduce an important finding with H-Form cavity, the Rayleigh number hasn't a strong effect on both the characteristics of the fluid flow and the temperature distribution for the values ranging from 10 to 104, unlike the case of square cavity. However, its effect starts to appear from Ra = 105. The achieved results are discussed and compared with preceding works in the literature to show their effectiveness. [ABSTRACT FROM AUTHOR]

This paper presents numerical investigations of the texture effect on deformation-induced surface roughening in surface-modified titanium specimens subjected to uniaxial tension. Three-dimensional polycrystalline models taking an explicit account of the grain morphology and crystallographic orientations are generated by the method of step-by-step packing. A crystal plasticity-based constitutive model describing the nonlinear behavior of individual grains is implemented in a dynamic boundary-value problem that is solved by the finite-element method. Two sets of calculations for polycrystalline models with textured and non-textured surface layers are performed. The basal texture of the surface layer is shown to effectively suppress surface roughening, both at the grain and mesoscales. [ABSTRACT FROM AUTHOR]

7xxx series aluminum alloys are used to manufacture machine components with good strength and low mass. The application of thin surface films can improve the erosion resistance of these alloys and their corrosion resistance, which are scarce. Low temperature PVD (Physical Vapor Deposition) coatings can increase the surface properties of the components without greatly influencing the mechanical properties. The deposition process induces high residual compressive stress on the surface, which favorably modifies the fatigue strength, but also defects, which have the opposite effect. The changes in fatigue behavior of 7075-T6 alloy induced by the deposition of a surface layer of PVD DLC (Diamond-Like Carbon) are described in this paper. The tests performed on some uncoated samples and others with DLC show that the fatigue strength of the uncoated samples is higher within 2·105 - 107 cycles range. The fatigue strength of the two kinds of samples is approximately equal within the range of 2·106 - 107 cycles. The failure mechanism is studied with the help of fracture surface microscopy and finite element analysis. The compressive stress state on the surface of the specimen associated with the surface layer deposition causes fatigue crack initiation under the surface of the specimen, if the sample does not present defects. [ABSTRACT FROM AUTHOR]

The paper deals with investigations of a crack propagating in a semi-circular concrete disc loaded in bending. Various crack inclination angles ensure different degrees of I+II mixed-mode conditions. Generally, concrete material exhibits quasi-brittle fracture behavior, which is difficult to describe. It has been shown that fracture in this kind of material occurs in a larger zone around the crack tip. Thus, the multi-parameter fracture mechanics concept can help to understand the facture response better. Particularly, the Williams power expansion with a selected number of its initial terms is used for approximation of the crack-tip stress/displacement field. The over-deterministic method together with a finite element analysis of the problem is used for calculation of the coefficients of the series. The deflection angle of the initial crack is then assessed via generalized/multi-parameter form of Maximum Tangential Stress (MTS) criterion in dependence on various parameters. The theoretical results are compared to experimentally obtained data. The results prove that the multi-parameter description of the crack-tip fields can bring more accurate assessment of the fracture response of a crack under mixed-mode loading. [ABSTRACT FROM AUTHOR]

In this paper we present the implementation of a stabilized finite element method (FEM) in the computational fluid dynamics code for numerical simulations of supersonic and hypersonic flows using the Flux Correction Transport (FCT), and the results of computational experiments. The instabilities observed in FEM numerical solutions for supersonic flows reflect the fundamental problems of the FEM, and cannot be avoided with any finite element approach modifications. The papers published for scalar transport, (Kuzmin 2009), and for compressible flow problem, (Kuzmin, Moller 2010) provided a break-through approach for this problem, resulting in algorithms of increased stability and performance, by implementing this on the level of the matrix of the algebraic linear system, resulting from PDE discretization in the FEM. The FEM with the FCT results in a stable algorithm for accurate simulation compressible flows, examples of simulations and comparisons are presented. An additional advantage of this approach is that simulations can be performed with a much larger time step, with the Courant-Friedrichs-Lewy (CFL) condition 1 or more (up to 20) and get numerically stable long time transient, and stationary solutions. This results in a significant speedup of simulations (up 30X) compared to maximum possible CFL=0.03 for methods without FCT. Apparently our FCT implementation FEM for supersonic flows was the first at a time successful implementation following the invention of FCT into FEM by (Kuzmin 2010). [ABSTRACT FROM AUTHOR]

Italy is a high seismic risk country. Since 1900 more than 30 earthquakes with magnitude greater than Mw=5.8 occurred, and the last one is the Central Italy seismic sequence. The first shock aroused in the 24th August (Mw=6.2) followed by another stronger quake in the 30th October (Mw=6.5). It heavily hit the regions of Marche, Umbria, and Abruzzo causing many deaths, injuries and extensive damages on the cultural heritage. This paper analyses the church of San Francesco in Amadola, located in the Marche region that has been considered condemned for the severe damages reported after these earthquakes. The church is globally analyzed by the application of nonlinear static analysis on a Finite Element Model where the nonlinearity of masonry is taking into account with a proper constitutive law. The study wants to prove how global analysis combined by the local analysis can reproduce the behavior of this structure during a quake, showing that it can repeat the real damages produced by earthquakes. [ABSTRACT FROM AUTHOR]

In this paper, it is presented the dependence of calculation and speed of calculation when increasing integration points in the finite element of the enrichment type, which is used in the eXtended Finite Element Method (XFEM). The Legendre polynomial was used to increase the number of integration points and the Gauss quadrature was used for integration. A simple 3D model consisting of hexahedron was created for testing. [ABSTRACT FROM AUTHOR]

The paper is focused on reliability analysis of time-consuming mathematical models utilizing approximation in form of Taylor series expansion. Statistical analysis is crucial part of reliability analysis of structures but it is still challenging to analyze time-consuming mathematical models, e.g. represented by finite element method in implicit form. Efficient alternative is an approximation of original model by explicit function in specific form. The paper is focused on approximation by Taylor series expansion for statistical analysis of functions of random variables. Although it is common to use Taylor series expansion for functions of uncorrelated random variables, it is challenging to utilize Taylor series for correlated variables and highly non-linear functions. Therefore, possibilities and pitfalls of such approach are herein discussed from engineers point of view. [ABSTRACT FROM AUTHOR]

Modeling of concrete response using nonlinear constitutive equations is currently a very popular and promising field of science. Nowadays, there is already a number of different constitutive equations (material models) intended for concrete modeling in computational systems. These equations find their use mainly in the implicit or explicit finite element method and usually contain a lot of input parameters. However, the still inadequate exploration of this field of science provides the scope for algorithmization and application of other constitutive equations that can provide satisfactory results with relatively few input parameters. This fact is related to the goal of this paper that is algorithmization and application of constitutive equations intended for modeling the plane stress state of concrete. These equations are based on the incremental theory of plasticity in which some aspects such as yield function, hardening rule, non-associated flow rule, plastic hardening modulus, and equivalent stress and strain are applied. Algorithmization of constitutive equations is performed in Matlab and their application is focused on the tasks of uniaxial and biaxial compression of concrete for the purpose of demonstration of their capability to describe the concrete response in compression very satisfactorily. [ABSTRACT FROM AUTHOR]

In recent years, Micro-Mechanical Systems has been active area of research for their wide range of applicability. Various bimolecular sensing applications like the detection of DNA, Proteins and Antigens involve the adsorption of molecules that results in the change of surface stress. The effect of surface stress on the cantilever deflection can be analyzed based on the pressure applied at the free end of cantilever. MEMs use Cantilevers as the basic structures for sensing. Yet the practicality has not been extensive due to their low resolution and expensive read out techniques. Various physical and process parameters play a significant role in ascertaining the responsiveness of a cantilever sensor. This paper presents the analysis on the effect of different designs of Stress Concentration Region (SCR) on the change in deflection in microcantilever using Finite Element (FE) analysis. Design and analysis were done using Intellisuite thermal, electrostatic and mechanical (TEM) analysis tool for MEMS design. By applying Finite element method the simulations are performed. Simulation results show that the cantilever with proposed rectangular SCR design gives the highest deflection thus contributing to the most significant result for cantilever readout. [ABSTRACT FROM AUTHOR]

This paper investigates the normal stress and shear strain of a single lumen microcatheter. A microcatheter is a nominally invasive device used in intracranial and neurovascular therapeutic disorders. Finite element method is used to analyze the stress-strain variations in all the three layers of the microcatheter. The stress-strain distributions are studied to incorporate an efficient and robust design to improve tractability of the microcatheter. The main objective of this paper is to make the microcatheter cost effective for the society by employing a robust design. A novel design of the microcatheter is done using a high-end three-dimensional modelling software inhibiting bends along the length to determine the failure criterion in one or all the three layers. The design of the braiding can be re-calibrated such that it can avoid shear failure of the inner layer. The dorsal tip of the microcatheter can be programmed using artificial intelligence using smart alloys (SMA) on the inner surface so it can take any shape according to the pathway inside the body. [ABSTRACT FROM AUTHOR]

In this paper micro-electro-mechanical systems (MEMS) deformable mirror (DM) for its use in adaptive optics in Indus-2 is studied. DMs are used to correct optical aberrations by precisely adjusting the deflection of mirror surface. A piezo based micro-actuator array of 19 keystone shape elements in diameter of 10 mm on silicon of 20 µm thickness is considered for the study. The finite element method (FEM) simulations were carried out using COMSOL Multiphysics 5.4 to estimate the displacement profile. In order to evaluate the applicability of this MEMS based DM in adaptive optics system, piezo response function matrix was determined by applying dc voltage of 1volt to each actuator one by one while keeping the others at zero voltage. The optimum voltage of each actuator to produce a target profile was determined using TLBO algorithm in MATLAB. In this way the obtained voltages are used to generated the low order Zernike mode shapes. [ABSTRACT FROM AUTHOR]

Metaheuristic algorithm is preferred by the many researches to find the minimum weight of truss structures considering size and/or shape design variables which are the truss element’s cross-sectional area and joint coordinates of the geometry of the trusses for the size and shape optimization, respectively. The design of plane and spatial truss structures are optimized by a popular metaheuristic optimization technique named Teaching-Learning-Based Optimization (TLBO). Finite element analyses of structures and optimization process were carried out by the computer program coded in MATLAB visually developed by the authors. Two benchmark problems (37-bar, and 72-bar) taken from literature were optimized and the optimal solutions belong this paper were compared with previous studies. [ABSTRACT FROM AUTHOR]

The paper presents the influence of dynamics of temperature field on three-layered annular plate with elastic and viscoelastic core. Plate is mechanically loaded in the plane of facings on outer perimeter with the forces quickly increasing in time. Temperature field is determined by the temperature difference between the plate edges, which increases in time with the adopted value of thermal rate. Problem is solved analytically and numerically using the approximation methods: orthogonalization and finite difference. To compare the plate reactions the model built in finite element method has been examined, too. Presented results show the meaning of the dynamic parameters of both mechanical loading and thermal field on the plate respond. The direction of the gradient of temperature difference causes the increase and decrease in values of critical plate parameters and can be the means of controlling of plate work in dynamic conditions. [ABSTRACT FROM AUTHOR]

This paper is concerned with the numerical solution of the structural optimization problem for bilateral frictional contact problem where the static elasto-plastic material model with linear kinematic hardening rather than elastic material model is assumed. The displacement and stress of the bodies in elasto-plastic contact are governed by the system of the coupled variation a line qualities. The contact stress usually is very high in central part of the contact zone and leads to wear or fatigue of the contacting surfaces. Therefore the aim of the structural optimization is to find such shape of the domain occupied by the body in contactor such distribution of the material filling this body to minimize the contact stress. Using von Mises yield function as well as the regularization and penalization techniques the original system of variational inequalities is transformed into the system of non linear equations. The shape derivative of the cost functional with respect to the perturbation of the domain is calculated using the material derivative method. Finite element method is used as the discretization method. In the numerical computations generalized Newton method is used to solve the contact problem. The level set method is used to describe and govern the evolution of the domain shape in the design space where the direction of the evolution is determined based on the calculated shape derivative. The results of computation are provided and discussed. [ABSTRACT FROM AUTHOR]

The Bonded repair is broadly used in aging aircrafts to improve the structural integrity of damaged aircraft panels. The aim of this paper is to study the behaviour of multiple cracks on the flat panels using FEA. In this paper two twin collinear cracks are modeled and analyzed in terms of stress intensity factor(SIF). To improve the strength of the panel with multiple cracks it is repaired by adhesively bonded composite patch. It is shown that bonded repair reduces SIF near the crack tips of multiple cracks. Further, the adhesive is the weakest link which undergo failure under the applied load. Hence in this work debonding analysis of patch from the panel is carried out by appling load in increments. From the debonding analysis it is observed that the debonding of patch reduces the strength of repaired panel and leads to rise in SIF at the crack tips. [ABSTRACT FROM AUTHOR]

The Main Spillway and Diversion Tunnel construction at the Manikin Dam, Nusa Tenggara Timur, is constructed in a claystone Bobonaro Formation. Alongside the construction process, this paper aims to evaluate the engineering geological condition and tunnel excavation method that is expected to provide technical consideration in the process of selecting the fieldwork method. Field investigations were carried out in evaluation of rock mass quality for tunnel boring log. The Rock Mass Rating (RMR) method determines rock mass quality. Subsurface samples were laboratory tested for soil/rock parameters in numerical modeling using the finite element method with numerical evaluation by Phase2 (Rocscience) software. The results of tunnel modeling are in the form of displacement with additional effect earthquake analysis and without earthquake analysis (static load). As a result of subsurface geological mapping, the dominant lithology which passes through the tunnel is scaly clay with the category of rock mass quality as Poor Rock and Fair Rock. Based on the Bieaniawski (1989), the excavation method can be multi drift, benching, or full face. The multi drift excavation method is estimated to earn a lower displacement value than other methods. It produces an estimated roof strength factor value of >1.25, which indicates the tunnel construction is in stable condition. [ABSTRACT FROM AUTHOR]

Transmission towers are vital channels for distributing high-voltage electrical power from power plants to substations. This infrastructure is the backbone of a productive modern society. However, a number of these towers may fail due to earthquakes. This failure may disrupt the electrical network, yield a substantial amount of replacement cost, and, more importantly, interrupt recovery efforts and business operations. This paper presents attempts to analyze the seismic risk of the transmission tower by developing its fragility curve. Fragility is defined as the probability of damage exceeding a certain level, given an extensive range of seismic intensity. A finite element computational model was analyzed under a nonlinear static procedure (pushover) to obtain a nonlinear response, specifically a capacity curve. Then the fragility analysis was performed by determining certain damage states in the capacity curve. The inter-segment drift ratio (ISDR) was employed for the damage states. The result is expressed as a fragility curve that provides fundamental and rational insights into the mechanical and probabilistic performance of transmission towers. [ABSTRACT FROM AUTHOR]

On April 10th, 2021, 3296 houses suffered light damage, 1964 houses suffered moderate damage, and 1552 houses suffered severe damage due to the earthquake that occurred in Malang, Indonesia. The iMPact on public facilities included 203 damaged schools, 16 damaged health facilities, 171 damaged places of worship, and 40 other damaged public facilities. Most of the damaged buildings were non-engineering buildings with various types of damage. In Pacitan Regency, there are many low-rise to medium-rise non-engineering buildings. In addition, Pacitan Regency has a coastline that is part of the Indonesian Ocean and is located very close to the subduction zone between the Indo-Australia plate and the Eurasian plate. The main potential sources of earthquake and tsunami events in this region are thrust systems. Seismic fragility curves play a pivotal role in the assessment of the comprehensive vulnerability of civil infrastructure to prospective seismic events, as well as in the anticipation of the consequential socioeconomic repercussions. This paper presents an analysis of the fragility of non-engineering buildings and estimates of their collapse using the finite element method. Seismic fragility analysis produces fragility curves that show the probability of structure damage under various damage conditions. [ABSTRACT FROM AUTHOR]

In the world of technology, where technology helps to explore almost everything, including outer space, planets, etc. However, due to the unknown extreme conditions at unexplored places, there is an interest and need to develop a technology which helps explore more about space. Here, we attempted to develop the Artificial Intelligence (AI) enabled rover model to be used for such space exploration scenarios. In this paper, firstly, finite element method (FEM) based design and analysis of the rover model are discussed. The operational and constructive features are explained, such as the real-time camera feed feature, measuring the temperature and humidity values, and detecting the object while measuring the obstacle distance. The AI-enabled rover model uses a real-time object detection algorithm which helps to analyze the object in a real-time manner. The rover model is designed in such a way that it can easily climb on different surfaces having obstacles. The rover model is then fabricated, where wheels are made from a buoyant substance such as polyvinyl chloride (PVC). A special suspension frame based on a modified rocker-bogie system is created to adapt the walker to uneven ground. This means that even in hostile surroundings, the rover can explore independently. The proposed model has a comparable cost as compared with published literature work. [ABSTRACT FROM AUTHOR]

Wind turbines are considered one of the tallest buildings vulnerable to lightning strikes as they lack a protection system for large-scale carbon-fibre epoxy composite structures. Blades are more affected by lightning due to their large scale, which is the highest point in wind turbine structure. Knowledge of cloud-to-ground (CG) lightning, lightning protection system (LPS), electrical field relation and receptor configuration are explained. A design from an actual wind turbine blade is used to study the effect of lightning. The receptor plays an essential role in determining the efficiency of (LPS). To investigate the impact of receptors with different shapes and sizes, two different types of lightning protection receptors are used to perform their effect on lightning. Three different radius of lightning copper receptor disks, 0.1m, 0.2m and 0.4m, have been tested. A triangle with a head to the downside simulates the lightning terminal. This paper is aimed to study and analyze the most suitable lightning protection for wind turbine blades to suggest the best parameters for receptor type and size. The electromagnetic Finite Element Method simulation recommends the minimum and maximum electric field that builds up around receptors, which has been used to determine the correct size and forms of receptors. Results from the lighting strike Simulation 0.1m receptor gives the highest value of electrical field interception 56.3MV/m compared with larger size receptor 0.4m with 18.7MV/m. This research revealed the effectiveness of different types of lightning receptors and the effect of the receptor's radius, which will offer better protection to the wind turbine [ABSTRACT FROM AUTHOR]

The dynamic behaviour prediction scheme of contact surface of bolt joints has found to be extremely difficult to model due the complex behaviour of the structural joints. In this paper, the bolted structure was used with aim to investigate the dynamic behaviour of the bolted structure using practical modelling scheme via finite element modelling and updating method. A simplified FE model of the bolted structure was developed using CBEAM element to represent geometrical shape of the bolt and Thin Layer Element (TLE) was used to represent the contact surface of the bolted structure. Subsequently, the normal mode analysis using NASTRAN103 was used to predict the dynamic behaviour of the FE model. Potential updating parameters of the FE model was analysed by implemented sensitivity analysis formulated in Nastran SOL200. The model updating method is then used to update the initial FE model of the bolted structure based on the experimental modal analysis (EMA) result. The comparison of the results is used in verifying the accuracy of the updated FE model of the bolted joint structure. The result suggested that the CBEAM and TLE can be used efficiently to represent the bolted joints and the contact surface of the bolted joint of the assembled structure. [ABSTRACT FROM AUTHOR]

This paper uses the Ritz method to find approximate solutions to boundary-value problems for ordinary differential equations. We present the approximate finite element solution by a linear combination of the basis functions. Here we get co-efficients of the optimal interpolation formula in W 2 (1 , 0) space as basis functions. The difference obtained in numerical results and exact solutions illustrates graphically. [ABSTRACT FROM AUTHOR]

In the present paper algorithms for constructing a finite element mesh of compound domains and minimizing the ribbon width of the system of resolving equations by the finite element method (FEM) are considered. A technology for constructing a finite element mesh by connecting elementary subdomains, a semi-automatic method for partitioning a two-dimensional multiply connected domain with a curvilinear boundary, and ordering the node numbers of a finite element mesh is described. In this case, the algorithms allow, by ordering the numbering of nodes, to determine such a sequence in which the ribbon width of non-zero coefficients of the system of resolving equations by the FEM will be locally minimal. [ABSTRACT FROM AUTHOR]

In this paper, a simple and compact ultra-wide band (UWB) microstrip planar antennawhich is fed by a co-planar waveguide (CPW) is developed and analyzed. The proposed design is setup on a FR-4 substrate with a dimensionof 31 x 34 x 1.6 mm3 with a di-electric constant (εr) of 4.4. The patch is a combination of two elliptical shaped structures with two slots etched on it. The proposed antenna operates at frequencies ranging from3 – 12.53 GHz with resonance frequencies at 3.95 GHz and 9.2 GHzhavingreturn loss of -22.21 dB and -32.97 dB respectively. The variation of the slot area and the length of ground is analyzed. The proposed antenna can be best suited for the applications where ultra-wideband is preferred which include WLAN, WiMAX, ISM, satellite frequency bands that include S-band, C-band, X-band and also ITU band. The design and simulation are carried out using the Ansys HFSS Tool version 2021.2, which is based on the Finite Element Method (FEM). [ABSTRACT FROM AUTHOR]

This paper presents modelling of small-scale axial flux permanent magnet synchronous generators that could be utilized for extracting the hydropower from wastewater treatment plants. Cored and coreless axial flux synchronous generators are analytically designed based on sizing equations. For validation, finite element-based models of different topologies are established and a comparison is held between the analytical design and finite element model results. To overcome the drawbacks of cored and coreless models, a new hybrid half cored half core less model is suggested by decreasing the stacking factor ratio, which saves more than 50% of steel in yokes but at the cost of lowering the output phase voltages. Therefore, a sensitivity analysis tool based in the finite element software is used to enhance the electrical performance and fulfill the required generator specifications. Lastly, a comparison is held between the different models; highlighting the promising outcomes of the proposed hybrid half cored half coreless generator relating to the enhanced performance at reduced active material requirements. [ABSTRACT FROM AUTHOR]

The use of externally bonded Fiber Reinforced Polymer (FRP) systems is becoming more relevant due to their superior performance in many structural applications. However, fire or elevated temperature exposure is a major concern for FRP systems due to the deterioration of the epoxy adhesive. This paper investigates the fire performance of unstrengthened and Carbon FRP (CFRP) strengthened Reinforced Concrete (RC) columns with and without fireproofing insulation. Four columns were modeled using the finite element software package ABAQUS to carry out the heat transfer analysis. All four columns were exposed to fire according to the ASTM E119 standard fire curve with an exposure period of three hours. The temperature-time curves were plotted 50 mm deep into the concrete, and 100 mm deep into the concrete, and at the longitudinal reinforcement. The results showed no noticeable improvement in the fire performance of RC columns with the addition of CFRP layers, where the temperature readings were almost the same. However, the use of the fireproofing insulation significantly affected the fire performance where the temperature at different times was significantly lower for the insulated columns compared to the uninsulated columns. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to demonstrate the convergence of a mixed finite element formulation in 3D for a nonlinear eddy current problem encountered in the modelling of Type II superconductors. The eddy current problem models the magnetic field in a material with a power law magnetic resistivity which makes it an analogue of the p-Laplacian. Yet in contrast to the p-Laplacian, the resulting time-transient degenerate parabolic problem includes a divergence constraint and requires non-conforming elements. Numerical discretizations of this problem, sometimes referred to as the p-curl, have been studied by many, but the well-posedness of mixed formulations has only been established in 2D by Prigozhin and Barrett. This research extends earlier work of Farhloul on the p-Laplacian and discusses well-posedness both for the continuous and the discrete formulation using first-order Nédélec elements. [ABSTRACT FROM AUTHOR]

This paper deals with a slat chain conveyor for the transport of rock materials in very severe abrasive conditions. An actual case from practice is discussed and analysed. To clarify the fatigue damage of the chain link material, the finite element method (FEM) is applied. For the experimentally recorded cycle of chain loading, numerical analysis has been performed and data for the damage of the link material are presented. Fatigue analysis is performed by ANSYS nCode DesignLife under different loading cases. FEM results show, that the fatigue crack of the link starts from region with high values of the stresses, established by experiment. [ABSTRACT FROM AUTHOR]

Leaf springs are utilized in vehicle suspension systems, these springs assist to support the complete weight and it offers comfort to passengers and language by minimizing the vertical vibration because of road. Leaf spring was invented by "Obadiah Elliott" leaf spring consists of two ends they are known as eye ends. With the help of these eye ends the leaf spring is attached to the body of vehicle. In this paper we have taken parameters from Mahindra commander 650 Di jeep and we have done comparison of a multi-leaf spring with EN45 steel material and Structural steel material. The 3-D design of multi leaf spring is performed in CREO Parametric after that we imported the design into ANSYS Work bench. We have performed the Structural analysis and Fatigue and Harmonic Response in ANSYS work bench. When we apply the P1 load(9000N) on EN45 Steel the results are the maximum deformation was 4664.2 and maximum Stress was 1.0741 and maximum Strain was 0.49166 and FatigueLife was 1e^6 and Safety Factor was 15 Max and Harmonic Response was 6.0252e^-2. When we applied P1 load(9000N) on Structural Steel the results are as follows the maximum deformation was 7304 and maximum Stress was 1.0815 and maximum Strain was 0.77387 and Fatigue Life was 1e^6 and Safety Factor was 15 Max and Harmonic Response was 6.1457e^-2. When we apply the P2 load on EN45 Steel the results are the maximum deformation was 3627.7 and maximum Stress was 1.0111 and maximum Strain was 0.3824 and Fatigue Life was 1e^6 and Safety Factor was 15 Max and Harmonic Response was 4.6853e^-3. When we applied P2 load on Structural Steel the results are as follows the maximum deformation was 5680.9 and maximum Stress was 1.0181 and maximum Strain was 0.06019 and FatigueLife was 1e^6 and Safety Factor was 15 Max and Harmonic Response was 4.78e^-2. [ABSTRACT FROM AUTHOR]

A finite element analysis on crash box of an automotive bumper system is presented in the paper to investigate the energy absorption of the component with and without foam-filled steel sheet metal tubes of different thicknesses for crashing or low-velocity impact analysis. The energy absorption capacity of the crash box for crashing is evaluated for different design changes of the foams-tube structure and compared the results without foam. By changing the different foam materials, various designs are proposed and simulated for maximum energy absorption. Altair Hyperworks is used for preprocessing and post-processing and Radios solver is used to run the analysis. A reasonable agreement is obtained in the results of the analytical and numerical methods. The results indicate that the energy absorption of a foam-filled crash box structure is superior to the crash box without foam. [ABSTRACT FROM AUTHOR]

Polymeric insulators are among the most crucial components in a power transmission system. The electric field (EF) distribution and voltage on the insulators' surface affect the insulators' performance and service life. Several experimental and numerical methods for calculating and studying the EF. This paper utilized corona rings at both ends to minimize the value of the EF and improve potential distribution along the surface of the 765-kilo Volt polymer insulator-based two-dimensional finite element method (FEM). At first, the mathematical relationship linking the EF to the parameters of the corona rings (corona ring radius, ring tube thickness, and vertical location of the ring) was established to calculate the EF strength and influence of the corona ring parameters. Then, optimization techniques within the COMSOL Multiphysics are utilized to optimize the position and diameters of the corona rings and lower the EF at the insulator's surface. According to the results, the optimization procedures utilizing the Nelder-Mead technique reduced the high value of the EF by 70% compared to the EF value with the original corona rings. [ABSTRACT FROM AUTHOR]

This paper will focus on the analysis and calculation of the Reactor Pressure Vessel (RPV) for a 10 MWt HTGR reactor that had been studied in previous research before. It got some data like the thickness of the reactor pressure vessel on the upper– bottom and the stress of the material structure, but there is no data on how to get it. This research will use other methods like Finite Element Analysis (FEA) and ASME code for safety standards. The maximum stress on the geometry exceeded the allowable stress, but the average was still below the allowable stress. These phenomena are due to the surface of the reactor pressure vessel given a load simulation like pressure and temperature on the support lug will be restrained so that the stress will be more significant. Therefore, it needs to modify to get below the allowable stress. The modification of the RPV support lug should refer to some type of reactor. After it, the stress shows the support lug is closer to the safety standard of ASME code section III. [ABSTRACT FROM AUTHOR]

In this paper, an equivalent dynamic modeling method of honeycomb sandwich structure is presented. An equivalent model is proposed depending on three equivalent dynamic methodologies for honeycomb panel modeling, a method depending on server panel theory, a method depending on Hoff's theory (1948), and Gibson's method. The dynamic analysis is performed based on finite element models, which are compared with the three developed methods and the empirical test presented in the previous model analysis. The optimal method for dynamic were echometric modeling of honeycomb-shaped buffer plates was verified. Hence, the differences in the results are promising because the proposed models are compatible with the theoretical analysis and the experimental structure used in the previous research. The dynamic results showed that the geometric variables and material properties have significant effects on the dynamic behavior of the honeycomb panel, which proved the validity of the equivalent method. [ABSTRACT FROM AUTHOR]

Composite material combines two or more materials into one combined material to get the desired characteristics of each material. Functionally Graded Material (FGM) is a type of composite material that combines two materials in the form of gradation of materials that is being developed as an alternative to the conventional composite material. To support this material, numerical simulation by the Finite Element Method (FEM) is very interesting. In this paper, the Discrete Shear Beam Element (DSB) element is used to evaluate the effect of the shear correction factor in FGM beam structures. In much of the literature, the shear correction factor is assumed to be constant. This assumption is correct for isotropic structures, but in FGM structures, this factor is not constant. A simply supported beam with various boundary conditions and thickness length ratio is evaluated to understand the effect of this factor. The results show that by using the true shear correction factor, the results will be close to the reference solution. Moreover, for the FGM beam with the significant ratio of modulus elasticity, the use of the true shear correction factor is a must to get a solution as close as possible to the reference solution. [ABSTRACT FROM AUTHOR]

Cultivator is a tractor operated cultivating tool that plough the land by using shovels. In a cultivator shovels are the main critical parts that are used to make the land. Shovels interact with land in such a way that, they are subjected to impact and high friction that causes wear. Hence, it is important to design and optimize the shovel so that its durability is improved. The depth of theshovel depends on the geometry of the blade. This paper presents the use of CREO in designing and optimizing of shovel on the basis of finite element method. The working in present work was done based on geometric parameters such as angle with horizontal axis, tip length, width and radius of the shovel. The results reveals that shovel depth can be increased by increase in the tip length, angle with horizontal axis, radius of shovel. [ABSTRACT FROM AUTHOR]

The following paper aims to provide a detailed analysis of the effect of different cutting speeds in the face milling of AISI 1045 steel using coated tool. Simulations would aid in solving problems associated with experiments, leading to reduced costs and risks. DEFORM 3D is a commercially used simulation software capable of implementing machining simulations using the theory of finite element modelling. A conventional DEFORM 3D milling model has been prepared for the analysis of cutting forces and chip formation and the simulation has been carried out for two conditions. The temperature and force parameters were analyzed after carrying out the experiment and simulation under the influence of different machining and environmental conditions. The results of the simulation revealed that the predicted values of FEA possess good accuracy. [ABSTRACT FROM AUTHOR]

Numerical optimization technique in tribo-contacts is becoming crucial area of investigation during the last few years. This article illustrates the use of genetic algorithm optimization technique in textured hole-entry hybrid journal bearing system. In this paper, the texture surface parameters are optimized by multi-objective genetic algorithm to developed modified Reynolds equation. The modified Reynolds equation has been solved by finite element model for obtaining the bearing performance parameters. The static and dynamic performance parameters of hole-entry hybrid journal bearing have been simulated for non-textured, textured without GA and textured with GA surfaces. Based on the simulated results, the study indicates that the textured hole-entry journal bearing with genetic algorithm technique significantly enhanced the bearing performance. [ABSTRACT FROM AUTHOR]

The numerical study presents the effect of heat generation and chemical reaction on the problem of magnetohydrodynamics mixed convective flow of power-law nanofluid using Buongiorno's model. Adiabatic non-conducting solid square block is located at the center of the cavity and both vertical walls are moving with uniform velocity. The governing dimensional equations in vector form are transformed into non-dimensional form. Then, the dimensionless equations are solved numerically by finite element method (FEM) using automated solution technique which is FEniCS. The effects of different parameters such as Richardson number, power-law index, magnetic field, heat generation/absorption, chemical reaction and size of square block on velocity, temperature, and concentration profiles are performed and discussed in this paper. It is found that rising both Richardson number and power-law index lead to increase the velocity and temperature profiles (right side of cavity). Besides, rising both magnetic parameter and size of square block lead to decrease the velocity and temperature profiles (right side of cavity). Adding the heat generation/absorption parameter has increased the temperature profile. In addition, increasing chemical reaction parameter has reduced the concentration profile. [ABSTRACT FROM AUTHOR]

The weighting finite element method (WFEM) is constructed to find an approximate solution to boundary value problems with a corner singularity. WFEM allows you to find a solution without loss of accuracy. This method includes three control parameters on the values of which the accuracy of finding a solution depends. This paper proposes an approach to determining the set of the optimal parameters for the weighting finite element method for the crack problem. [ABSTRACT FROM AUTHOR]