Static Structural Analysis Research Articles

Optimization of a knee implant with different biomaterials using finite element analysis

The current study aims to examine the stress behavior along with the Knee Implant components namely femoral, tibial cushion, and the tibial insert where the femoral and tibial insert components are made of Ti–6Al–4V alloy and the tibial cushion component is varied with different polymer-based biomaterials like Ultra High Molecular Weight Polyethylene (UHMWPE), Poly-Ether-Ether-Ketone (PEEK) and Polymethyl Methacrylate (PMMA). A three-dimensional (3D) computer-aided design (CAD) of knee implant is prepared using Autodesk Fusion 360 modeling software. The static structural analysis is carried considering a load of 2000 N (3 times the body weight of an average 68 kg person). Three material models are used in which the femoral and tibial insert materials are kept constant and only the tibial cushion material is varied. The purpose of this study is to test the applicability of PEEK and PMMA bio-materials in the field of knee prosthetics using a numerical approach. The PEEK and PMMA materials are mostly used in spinal implants, dental implants, and hip replacement surgeries which need to verify using Finite Element Analysis (FEA). The static structural deformation and the von-Mises stress behavior of the femoral, tibial cushion, and tibial insert are analyzed and studied. The Material Model (MM-I) with a tibial cushion made of UHMWPE material, and the femoral and tibial insert made of Ti-6Al-4V alloy shows better stress behavior (Minimum stress generation) than the other material models. This study validates the reason for preference of UHMWPE material over any other biomaterial, for the tibial cushion component of a knee implant.

Geometry design and optimization of piston by using finite element method

The piston performance may be impacted by piston geometry, stress, temperature and deformation applied. Thus, the purpose of this study is to investigate the changes of piston performance with different piston head designs. Besides, the piston is optimized by using topology optimization to remove excessive material. The study was carried out by using the dimension of a piston based on the cylinder of a spark ignition engine. The four piston head designs are flat-top piston, bowl piston, square bowl piston and dome piston. All four piston designs were modelled by using Solidworks. Static Structural and Steady State Thermal Analysis in ANSYS Workbench were used to analyze the piston performance. The measured parameters are stress, deformation and temperature distribution. Next, optimization of piston was done by using topology optimization to identify non-essential parts that can be removed. The optimized piston design was analyzed. The findings for the original and optimized piston geometries were tabulated to make comparison. It is found that bowl piston has lower stress, deformation and temperature. The stress, deformation and temperature of optimized piston is lower than original piston. The mass of optimized piston is about 5 percent lesser than the original piston.

Table-Top Lithium Disilicate Ceramic Restoration Thickness Effect on the Stress Distribution in Upper Premolars: 3D Finite Element Analysis

To evaluate the stresses generated in upper premolars rehabilitated with ceramic fragments (table-top) of lithium disilicate on the occlusal surface. An upper premolar was modeled following its anatomical references using computer aided design software (Rhinoceros version 5.0 SR8, USA). The dental tissues were individually designed containing enamel, dentin and periodontal ligament. The main anatomical points were used as parameters for model creation. Ceramic fragments were modeled varying their maximum thicknesses as: 0.5 mm, 1.0 mm and 1.5 mm. Solid geometries were exported to the analysis software (ANSYS 17.2, USA) in STEP format. The materials were considered isotropic, homogeneous and linear, and the values of the elastic modulus of the materials and structures were used to perform a static structural mechanical analysis. The set was submitted to 200 N load. The system fixation was defined on the basis of the three- dimensional model, and the results were obtained in MPa according to the failure criteria of the analyzed materials (tensile stress). Occlusal restoration was not detrimental to mechanical behavior. Stress distribution in the internal region of the restoration was similar between the groups. Thicker fragments presented a lower concentration of tensile stress, therefore suggesting better prognosis in attenuating tensile stresses in the tooth region. More conservative occlusal ceramic fragments presented worse prognosis. However, all evaluated thickness for table-tops support the occlusal rehabilitation of upper premolars when submitted to 200 N loading.

Hinge-type FBG acceleration sensor based on double elastic plate

It is critical for the health monitoring of large-scale structures such as bridge, railway and tunnel to acquire the medium-frequency and high-frequency vibration signals. To solve the problems of low sensitivity and poor transverse anti-interference of the medium-frequency and high-frequency fiber acceleration sensor, a hinge-type Fiber Bragg Grating(FBG) acceleration sensor based on double elastic plate has been proposed, and the hinge and elastic plate are used as elastomer to realize the miniaturization and transverse interference suppression of the sensor. The MATLAB and the ANSYS are used for theoretical analysis and optimization of sensor sensitivity and resonance frequency, structural static stress analysis and modal simulation analysis, while the test system is built to test the sensor performance. The results show that the resonance frequency of the sensor is 1300 Hz; the sensor has a flat sensitivity response in the middle-high frequency band of 200–800 Hz; the sensitivity is about 20 pm/g, and the fiber central wavelength drift and acceleration have good linearity and stability, while the transverse anti-interference is about 3.16%, which provides a new idea for monitoring of medium-frequency and high-frequency vibration signals in large-scale structures.

Prestress behaviour and ductility requirements in structures: solutions from a unified algebraic approach.

This paper presents an algebraic approach that unifies both the elastic and limit theories of static structural analysis. This approach reveals several previously unpublished improvements, which are based on several dualities in the mathematical description. Firstly, we show a novel duality between the solutions to two different problems: the elastic solution to the internal forces of an externally loaded structure, and the nodal displacements induced by prestressing in one or several elements of the same structure. This duality is proven and discussed. The application of this solution to the limit state analysis is very productive, and includes the determination of the ductility requirements necessary to achieve full plastic behaviour, and the assessment of the prestress needed to limit or eliminate such requirements. The unified framework also allows to obtain the elasto-plastic deformed state at the beginning of the plastic structural collapse. We have also detailed the theoretical duality between two classes of structures—hyperstatic and hypostatic—which was derived from the linear algebra principles that define these solutions. Finally, we studied and exposed the dimensionality reduction of structural problems given by the singular value decomposition and the eigenvalues problem. An illustrative example that clearly illustrates all these points is provided.

Modeling, structural and cfd analysis of mobile robot for banana cultivation

The banana plantation is a popular cash crop in southern parts of India. Globally, India ranks first in banana production by producing about 14 million metric tons annually. Cultivation of which involves humongous manual tasks with moderate difficulty, often the tasks are accompanied by considerable spending towards accomplishing those tasks. More often than not it affects the earning prospects of the farmer thus, succumbing to a great loss of investment. A valid solution to this problem from the technological perspective is to provide low-cost automation for the hectic tasks in banana cultivation. Through this work, a baby step towards addressing the issues in banana cultivation is initiated. This paper deals with the design, structural, computational fluid dynamics simulation of an Agricultural field robot for aiding banana cultivation by producing a plantation hole for banana seedlings. The conceptualized idea is modeled in 3dimension using SolidWorks software with suitable dimensions, then by applying desired material properties to the individual components a static structural analysis is executed on the assembly. After the completion of structural analysis, subsequently, CFD analysis is carried out with an Ansys-Fluent workbench on the equivalent solid modal replica of the assembly modal, developed exclusively to analyze the wind effects.

Linear static progressive collapse analysis of RC structures

When there is a sudden loss of load carrying element in a structure, the structure will choose alternate load paths until equilibrium is reached. In this process, elements overloaded in the alternate load paths fails, leading to a large damage disproportionate to the initial event which is referred to as Progressive Collapse (PC). Fire, gas explosions, terrorist attacks, car crashes, and improper design and construction are all common causes of progressive collapse. As a result, it is important to research and examine the effects of this phenomena on structures, as well as to reconstruct the structure to be resistant to it. Government buildings, hotels, offices and residential buildings require different spacings and may require large spans. Though lot of research work has done on PC resistance of Reinforced Concrete (RC) structures to explore that research, in this study, RC buildings with 4 m, 6 m and 8 m clear span between columns have taken and linear static analysis (LSA) has done for different column removal conditions. PC resistance is measured in terms of vertical joint displacement (VJD), chord rotation (CR) and demand capacity ratio (DCR). The VJD and CR results are discussed and compared with each other. The calculated CR values and DCR values are compared with the limiting value as mentioned in GSA and DoD. The tendency to PC is more for 8 m span model is more than the other models with 6 m and 4 m.

Static and dynamic analysis of three-layered partial-interaction composite structures

The static and dynamic behavior of three-layered composite structures is investigated in the present work through the presently proposed finite-element (FE) expressions. Relative to most research on partial-interaction composite beams, the present numerical method is developed through considering independently assumed interlayer slips and transverse shear deformations among sub-elements, the latter of which are based on the Timoshenko’s beam theory. Variational method based on the minimum potential energy principle is delivered to establish the static and dynamic stiffness (and mass) matrices for the partial-interaction composite beams. The present results are validated against the analytical and numerical results from limited data presented in the literature where good agreement is generally obtained, giving credence of the present technique. What’s more, the present FE technique is also demonstrated to be advantageous in the following sense: 1) The introduction of the internal degrees of freedom significantly alleviates the locking phenomenon that is frequently mentioned in the literature; 2) Independently assumed rotations for three layers are necessary in predicting the global behavior of composite structures with significantly distinct material properties. It is finally concluded that the developed FE framework provides a stable and efficient tool in investigating the three-layered composite beams/columns in various perspectives and could be readily extended to composite structures with more complex geometries or loading conditions.

Comparative analysis and simulation of metal and non-metal polymer composite gears

In this paper, the study of analysis of spur gears and design principles maximum shear stress theory used for analytical calculation and in simulation analysis von mises theory is used in FUSION 360. The study static structural analysis of metal, non-metal polymer gears is mainly focused on the analysis of stress, strain, and pressure at the contact of teeth and factor of safety. Analyzing the stress, strain, pressure at the contact of teeth and factor of safety of metal and non-polymer-metal gears by using the material ductile cast iron and Nylon when both metal gears were in contact, both polymer gears were in contact and finally Metal and polymer gear in mesh with each other. Comparing the analytical results which were calculated from MSST (Tresca’s theory) and analyzing the all-mechanical properties of analytical results from von mises design theory which is used in Fusion 360 Simulation software. Comparing all the simulated results with different loading conditions when metal, polymer, and non-metal gears were in contact.

Stress Analysis of Composite Aircraft Wing using Coupled Fluid-Structural Analysis

Aircraft wings are designed with very low factor of safety to keep the aircraft weight minimum. Thus, for safe design of wings, stress analysis should be carried out under accurately estimated aerodynamic loads and this can be achieved only through coupled fluid-structure analysis. Moreover, modern aircraft wings are made of laminated composite structures and thus the purpose of this study is to employ ANSYS coupled fluid-structure analysis to find the best layup of composite wing of an aircraft that results in higher specific strength and specific stiffness. Firstly, Computational Fluid Dynamics (CFD) analysis has been carried out to find the actual aerodynamic load which is the pressure distribution around a three-dimensional wing. Then, this pressure distribution from CFD was used as a load input for detailed static structural analysis of the wing. Initially, strength and stiffness of an isotropic wing is evaluated and then the material of the wing was changed to composite laminates to achieve better structural performance with higher strength and stiffness to weight ratio. Stress analysis was carried out for different layups to predict the optimum layup that results in high strength and stiffness coupled with the least weight and it was found that the wing made of symmetric cross-ply laminate performs the best.

A CFD study on the structural parameters of NACA 2412 airfoil based air-wing using different composite materials

Weight is one of the important factors in aerodynamics; we need to reduce the weight of any flying object in order to get the higher lift force. Wight reduction of wing helps us to get better air craft efficiency and high performance. Aluminum alloys are used to make aircraft wing as it is suitable but in this study, we have used few light weighted composite materials for making the aircraft wing and other alloys as well where aluminum is used as the base material and it is mixed with other materials with different proportions for testing the performance. In this study, NACA 2412 airfoil has been chosen and the wing has been designed in Design Modeler 19. The model has been imported to ANSYS Workbench; the static structural analysis has been carried out by putting the required parameters. The objective of the study is to find out which material will be suitable for making aircraft wing among Carbon Fibers, Alpha-Beta Titanium alloy and Al-Zn-Mg alloy.

Conformational states and fluctuations in endothelial nitric oxide synthase under calmodulin regulation

Mechanisms that regulate nitric oxide synthase enzymes (NOS) are of interest in biology and medicine. Although NOS catalysis relies on domain motions and is activated by calmodulin (CaM) binding, the relationships are unclear. We used single-molecule fluorescence resonance energy transfer (FRET) spectroscopy to elucidate the conformational states distribution and associated conformational fluctuation dynamics of the two NOS electron transfer domains in an FRET dye-labeled endothelial NOS reductase domain (eNOSr) and to understand how CaM affects the dynamics to regulate catalysis by shaping the spatial and temporal conformational behaviors of eNOSr. In addition, we developed and applied a new imaging approach capable of recording three-dimensional FRET efficiency versus time images to characterize the impact on dynamic conformal states of the eNOSr enzyme by the binding of CaM, which identifies clearly that CaM binding generates an extra new open state of eNOSr, resolving more detailed NOS conformational states and their fluctuation dynamics. We identified a new output state that has an extra open conformation that is only populated in the CaM-bound eNOSr. This may reveal the critical role of CaM in triggering NOS activity as it gives conformational flexibility for eNOSr to assume the electron transfer output FMN-heme state. Our results provide a dynamic link to recently reported EM static structure analyses and demonstrate a capable approach in probing and simultaneously analyzing all of the conformational states, their fluctuations, and the fluctuation dynamics for understanding the mechanism of NOS electron transfer, involving electron transfer among FAD, FMN, and heme domains, during nitric oxide synthesis.

Design, Structural and Thermal Analysis of Piston by Using Finite Element Analysis

Abstract: In this project, it was chosen to investigate a specific piston design and its maximum gas pressure capabilities. The first aim for this project is to create a piston model using the solid modelling software CATIA V5. The geometry will be meshed and analyzed using the ANSYS software. A thorough literature search was conducted for the examination of piston input circumstances and the analytical process. High combustion gas pressures operate as mechanical loads, causing substantial strains in the piston's critical area. For various loading situations, such as maximum gas pressure load, a detailed static structural analysis is carried out. To choose the best material, a comparative research is carried out. Relative examination is never really dominated material. A cylinder is a mechanical part found in an assortment of cycles like pneumatic chambers. Responding siphons, responding motors and gas blowers. It is the upward development inside a chamber that is put away gastight by cylinder .In the auto business, it is found that the cylinder is the most fundamental part of the motor, and that it is presented to serious mechanical and warm loads. Warm burdens are initiated in the cylinder because of the exceptionally high temperature differential between the cylinder crown and the cooling displays. The cylinders are regularly built of aluminum due to its lightweight and heat conductivity. Be that as it may, as a result of its low hot strength and high development coefficient, it isn't suggested for use in high-temperature applications. The reason for a section bar or potentially an associating bar in a motor is to move power from growing gas to the barrel shaped shaft through an interfacing bar and additionally segment pole. To pack or remove the liquid put away in the chamber, the siphons turned around the capacity of the cylinder and communicate power from driving rod to it. In the initial step the primary examination of a common cylinder developed of the aluminum composite is concentrated in this exploration. The subsequent advance is to direct an investigation on a cylinder developed of Aluminum and Cast iron. Lightweight, minimal expense, primarily and thermally safe materials ought to be used in the development of pistons in the third step Validation of investigation result with contrasting the traditional material.

An alternative three-node triangular composite shell element in terms of Reddy-type higher-order theory

Composite curved shells are widely utilized as structural components in aerospace engineering. To inspire the potentiality of such structure, it is very necessary to well understand mechanical behaviors of composite curved shells. Compared to the composite plates, it is more difficult to predict accurately interlaminar stresses of composite curved shells. Therefore, this paper attempts to propose an alternative triangular composite shell element in terms of the Reddy-type global–local higher-order theory. In the present model, the continuity conditions of transverse shear stresses are enforced in advance to fulfill compatibility of transverse shear stresses at adjacent layers, which can improve precision of interlaminar stresses. In order to evaluate performance of the proposed shell element, several typical examples have been analyzed. Moreover, the results acquired from the present model are compared with the three-dimensional elasticity solutions and other published results. At the same time, a compression experiment of the thin-walled cylindrical grid structure is carried out to further verify the capability of the present model. These examples show that the proposed composite shell element can be used as an alternative method for static analysis of multi-layer thin and thick shell structures.

Stainless steel wave spring as vibration absorber for motorcycle: Design simulation and analysis

In the ongoing world, everyone has been using the shock absorber as an essential component in most places like load carriers, large structures, and automobiles. This shock absorber plays a crucial role in the vehicle suspension to absorb the major shocks. So, if we absorb the shocks more efficiently, we can reduce the damage to the vehicle body, passenger and also, we can give a comfortable drive to the driver. In the suspension system, spring is the major part to absorb shocks through spring energy. So, if we use different springs or if we can modify the existing spring with better efficiency then we can increase the shock-absorbing capacity. Based on these ideas, I worked on the comparative analysis between coil spring shock absorber and wave spring shock absorber using stainless steel material under static structural and random vibrational analysis. Through these results, we can understand how effectively the wave spring shock absorber can replace the coil spring absorber in terms of load and deformation. In the end, we can find the effectiveness of springs under different random obstructions using the PSD concept in Ansys. This work can be helpful to mono shock absorber bikes and in other places where springs are required at low space areas. If we replace the coil spring with a wave spring with the same length, we can absorb more vibrations at a more comfortable level for the drivers.

Semi-analytical solution for static and quasi-static analysis of an inextensible cable

The static and quasi-static analysis of cable structure and cable-driven systems is of significant interest to the researchers. In this paper, a semi-analytical solution for static equilibrium analysis of an inextensible cable is developed to know its initial configuration and tension. The analytical expression for the static equilibrium configuration of a cable, fixed at the two ends is generally available in the literature in terms of unknown reactions at the boundary nodes. Conventionally, researchers use numerical methods to solve for those unknown reactions at the boundary nodes, where a solution is sensitive to the initial guess. The proposed semi-analytical solution avoids such difficulty faced by an analyst or a designer of cable systems. The results obtained here were validated with a numerical solution for the static profile and cable tension. For the quasi-static analysis, these numerical methods are not suitable to compute the cable tension and its equilibrium profile due to the dependency of the solution on the initial guess and computation cost. To illustrate the need for a semi-analytical solution, the design problem for a cable support system and quasi-static analysis of an underwater tether connected between parent ship and a remotely operated vehicle (ROV) are presented. For the quasi-static analysis of the underwater tether, the proposed results are compared with those using the Newton-Raphson method in terms of computational cost and accuracy. In addition, guidelines are provided in this paper to choose an initial guess for the numerical approach so that a solution would be converged much faster.

Parametric nonlinear static analysis of a RC structure with TLCW exposed to bidirectional earthquake load by using different modelling methodologies

The seismic assessment of Reinforced Concrete (RC) buildings with Two Leaf Cavity Wall (TLCW) masonry infills requires reliable and computationally efficient numeric models. The current study has two main goals. First, to understand the contribution of TLCWs to the nonlinear response of RC buildings subjected to dynamic excitations. Second, to investigate the efficiency and accuracy of continuum-based Finite Element Modelling (FEM) approaches and simplified, structural Discrete Macro Element Modelling (DMEM) approaches in predicting the ultimate behavior of RC buildings infilled with TCLWs by performing pushover analyses. A half-scaled two-bay, two-storey RC building prototype infilled with TLCWs, experimentally tested on a shake table and already numerically investigated in the literature by FEM approaches, is considered with these aims. The responses of the FEM and DMEM models are compared to experimental observations in terms of pushover capacity curves and damage patterns. The analyses confirm the ability of the models to effectively predict the lateral deformability and lateral strength of the prototype with a satisfactory level of accuracy. However, some differences are observed in terms of the building's ultimate lateral strength, attributed to the effects of the boundary conditions at the base of the table, not explicitly described by the numerical models. The emphasis is given to the boundary conditions reached during the excitation of the scaled structural system via shaking table. Finally, in the last part of the paper, parametric analyses are performed on the DMEM model to evaluate the main material parameters governing the response of the building effected by the boundary conditions.

Structural Analysis on the Coil Spring of Motorcycle Suspension System

The motorcycle suspension system is one of the crucial components. It helps to support the motorcycle’s weight, isolate the vibration level caused by road imperfection, and keep the wheel in contact with the road surface. Therefore, the performance of suspension system needs to be enhanced to ensure the ride comfort and safety of riders. Coil spring is one of the essential parts of motorcycle suspension system. In this study, two different materials of coil spring are being focused include steel alloy and carbon fiber reinforced plastic (CFRP). The geometry of the coil spring is the existing design in the market. The static structural analyses are carried out to determine the directional deformation of y-axis, equivalent stress and equivalent elastic stress analysis of the corresponding coil spring material. The obtained results are discussed. It is found that the steel coil spring has better performance for the existing coil spring design. The directional deformation, equivalent stress and equivalent elastic strain of steel coil spring are considered at the lower side, which is 0.029357mm, 2003MPa and 0.010051mm/mm respectively. In this study, it is observed that the number of turns of coil spring should be increased to enhance the performance of CFRP coil spring.

PENGGUNAAN SISTEM STRUKTUR RANGKA ATAP TIPE PELENGKUNG 3 SENDI

So far, the system of the roof structure of residential and office buildings is dominated by conventional frame types. The use of a 3-joint arch structure system is only familiar to warehouse buildings and the like. The purpose of this study is to identify the feasibility of using type 3 joint arches on the roof of a residential building. The research scenario is focused on calculations using SNI 7973-2013, namely Design Specifications for Wooden Construction and Specific Static Structural Analysis Methods for 3 Joint Arch Structures based on the length of the truss span model, which is 9 m. The calculation result indicates that 1). The 3-joint curve type is worth using as it proves stable and safe 2). The distance between the truss of the roof truss affects the dimensions of the truss. The implication is that the construction of the roof of a residential house can use a 3-joint arch structure system while the basic material for modeling uses Code E20 wood material with Quality B, depending on the length of the span and the slope of the roof.

Coupling of non-conforming trimmed isogeometric Kirchhoff–Love shells via a projected super-penalty approach

Penalty methods have proven to be particularly effective for achieving the required C1-continuity in the context of multi-patch isogeometric Kirchhoff–Love shells. Due to their conceptual simplicity, these algorithms are readily applicable to the displacement and rotational coupling of trimmed, non-conforming surfaces. However, the accuracy of the resulting solution depends heavily on the choice of penalty parameters. Furthermore, the selection of these coefficients is generally problem-dependent and is based on a heuristic approach. Moreover, developing a penalty-like procedure that avoids interface locking while retaining optimal accuracy is still an open question. This work focuses on these challenges. In particular, we devise a penalty-like strategy based on the L2-projection of displacement and rotational coupling terms onto a degree-reduced spline space defined on the corresponding interface. Additionally, the penalty factors are completely defined by the problem setup and are constructed to ensure optimality of the method. This method is particularly suited for spline spaces of moderate degrees p=2,3, where the projection is computationally efficient and the condition number related to our choice of parameters does not yield a significant deterioration of the solution accuracy. To demonstrate this, we assess the performance of the proposed numerical framework on a series of non-trimmed and trimmed multi-patch benchmarks discretized by non-conforming meshes. We remark that only water-tight geometries have been considered in this work. We systematically observe a significant gain of accuracy per degree-of-freedom and no interface locking phenomena compared to other penalty-like approaches. Lastly, we perform a static shell analysis of a complex engineering structure, namely the blade of a wind turbine.