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This paper is on the design for manufacture and assembly of a paper cup making machine for a developing economy which can be locally manufactured within an income and expenditure that suits most small to medium businesses (SMEs). The current problem is that current computer controlled paper cup making machines on the market are expensive and therefore not affordable for a developing economy. Through wide research of how current paper cup making machines work, it was possible to come up with a low cost effective solution. A deeper understanding of the paper cup making machine was conducted with the aid of the internet, scholarly journals and industrial visits to local companies. The manufacture of this paper cup making machine is advantageous to a developing nation by creating jobs and thus eliminating poverty. [ABSTRACT FROM AUTHOR]

This paper is an extension of the study entitled "Finite Element Analysis in Footwear Engineering". The entire work presents how Finite Element Analysis (FEA) could be used in footwear engineering education as a sustainable tool to predict the designed product's behaviour before its manufacturing. Simulating the human walking movement helps to understand how certain combinations of materials or design parameters and decisions influence the final product. While the first part of the study is based on the description of pre-processing stages such as choosing equipment and materials, modelling and editing the geometry, the current paper describes the simulation and post-processing stages: setting the analysis requirements including connecting and loading conditions of the model, solving the model and analysing the results. The procedure is described based on three models of the same constructive type, namely Derby shoe. The position of the bar stitch varies in a vertical direction. The Static Structural analysis module of the ANSYS software application is used to simulate the behaviour of models and material structures. Each model's behaviour is analysed for three phases of the gait: heel strike, stance, and push off. Two parameters are evaluated and compared: total deformation and equivalent Von Mises stress, that allow estimating the strength of the seam, stress distribution, and deformation of the structure. The analysis shows changes in each phase of the gait under the influence of body weight. The methodology presented in this paper allows performing simple simulations without deepening on advanced mathematics, numerical methods, and computational implementation. [ABSTRACT FROM AUTHOR]

Finite Element Analysis (FEA) is a numerical method widely used in industry, research, and education fields. FEA exploits the properties and dimensions of the model discretised in a series of small regions called finite elements linked together at specific points which are called nodes. This paper demonstrates how the FEA could be used in footwear engineering education as a sustainable tool to predict the designed product's behaviour before its manufacturing. FEA-based simulations have substantial potential in footwear engineering training and education as it allows the students/designer performing static and dynamic analyses to represent the interaction between ground-sole-footwear-foot by analysing the shoe's design parameters' effects on the foot's load transfer. Based on the Finite Element Method (FEM) principles, a methodology for investigating footwear behaviour during normal walking is proposed, including preparatory, pre-processing, analysis, and post-processing stages needed to perform an FEA simulation. This part of the study explains the preparing and pre-processing steps: choosing equipment and software and performing the simulation by modelling and editing the geometry, explaining the role of materials and defining their properties. The pre-processing stages presented in this paper are essential for preparing the simulation process. The 3D geometry and materials influence the accuracy of the FE model and improve the analysis efficiency in engineering applications. Three models of the same constructive type, namely Derby shoe, show the herby described procedure. For these three models, the bar stitch's position varies in a vertical direction, and the material's properties are specified: foot, sole, uppers and bar stitch. [ABSTRACT FROM AUTHOR]

The wave piercing buoy in this paper is different with the traditional cylindrical buoy, it is made by ultra-high molecular weight polyethylene (UHMWPE) and has six middle pontoons. In order to guarantee the stability of the buoy structure, it is necessary to carry out the strength analysis. This paper use the ANSYS software to carry on the simulation analysis to the buoy, and the result of it is compare with the actual operation, therefore ensure the strength of the wave piercing buoy meet the related requirements. [ABSTRACT FROM AUTHOR]

This paper aims to provide the study of a design strategy for 3D printing production process, given its recent development, as well as that of high-performance materials. In particular, we focus on the blade of a wind generator by evaluating new construction methods deriving from new design approaches. The strategies used for the present study are described as follows: firstly, it was necessary to proceed to redesign the blade, by CAD software in order to menage a 3D model for the study and to initialize the whole project; then, the FEM analysis to validate the study. Finally, the AM (Additive Manufacturing) theorization and simulation for both a scaled blade and a full-sized one. The motivation behind this paper draws on the predominance and the constant evolution of the 3D printing in recent years, as well as the continuous research on both development and improvement of costs and performance of composite materials used. [ABSTRACT FROM AUTHOR]

The gas pipe in shield is one of the key parts of the long distance pipeline projects. It brings a great deal of uncertainty and risk factors for pipeline pigging operations. Paper establishes the finite element model, analyzes pig pigging and the impact over bending. Under the operating parameters of the pipeline pigging operations are given, paper develop the dynamic simulation model, analyzes the relationship among pipeline pressure, foam pigging speed and pipe stress. Through analyzing the motion law of acceleration and velocity, paper discusses the security of pipeline pigging operations. [ABSTRACT FROM PUBLISHER]

This paper will focus on the fast assessment methodology of FBGA fatigue life through simulation and physics of failure (PoF) analysis under thermal cycle. The structure of fine pitch ball grid array (FBGA) that has been investigated, and been modeled by ANSYS to compare with experimental data. There are two temperature cycling will be used, one is used to verify FEA model, and the other one is used to do failure analysis. The aim of this paper is fist discussing the ability of finite element analysis (FEA) in executing the virtual thermal cycling reliability analyzing the reliability of solder joints fatigue life in local modeling. FBGA packages can warp due to local and global mismatch of the coefficients of thermal expansion and the asymmetric package geometry. Temperature cycling condition including dwell time and ramp rate is an important factor that will affect the solder joins reliability. This paper will identify the critical parameters that influence by using a Design of Experiments (DoE) approach using simulation results from ANSYS. Two types of analyses include the physics-based analysis and the statistical-based analysis. The paper presents the physics-based analysis, three steps, uses by DoE tool. The first step we have to select the parameters, such as PCB thickness, PCB Young's modulus, PCB coefficient of temperature expansion (CTE), solder joints height, die thickness, mold compound thickness, and so on. The second step is to find important factors. And the final step is going to DoE, in this paper used response surface methodology (RSM). The use of DOE and ANOVA to identify the critical parameters and a response surface to generate a functional form will be discussed. In this study, we will concentrate on the approach of deformation information to the critical stress. The critical stress is then fed into a fatigue damage model, which outputs life, or cycles to failure. Throughout the work, DoE and ANOVA techniques will be used to determine the key parameters and help in the development of a fast assessment model of FBGA fatigue life through simulation and physics of failure (PoF) analysis under thermal cycle. [ABSTRACT FROM PUBLISHER]

Composite beams are frequently used because of their competitive combination of a steel beam and a concrete deck. Further optimization of composite beams is possible through use of tapered steel beams. In terms of material reuse, composite structures generally underperform, because of the concrete casted in-situ. The most common shear connector is the welded headed stud embedded in the concrete. An alternative to welded headed studs is a bolted shear connector, which allows for demountability of the composite floor system and subsequent reuse of it. The goal of this paper is to propose a method to determine the deflection of tapered composite beams with flexible shear connectors. Starting point is the theory available in literature for straight (i.e. prismatic) composite beams with flexible shear connectors. The proposed method is used in a case study to optimize the design of a composite beam in a multi-storey car park. Validation of the derived hand-calculation method is carried out through finite element analysis. An approximation is derived based on which the deflection of tapered composite beams can be estimated through hand calculation, with a deviation less than 5%. [ABSTRACT FROM AUTHOR]

A three-dimensional dynamic solidification model incorporating the thermo-elastic-plastic coupling model has been proposed in this paper by ABAQUS considering the dynamic contact between the slab and rolls. The thermomechanical coupling model produces outputs such as temperature and mechanical behavior of the slab. And the stressstrain distribution of the high-temperature slab at the solidification end has been investigated in this paper. The influences of various reduction interval, reduction amount and reduction distribution on mechanical behavior of casting slab have been systematically discussed. [ABSTRACT FROM AUTHOR]

A discontinuous Galerkin finite-element time-domain (DG-FETD) code is developed to simulate some interesting and challenging antennas. It incorporates several advanced techniques, such as higher-order tetrahedral elements, conformal perfectly matched layer (PML), and local time-stepping scheme. To further speed up the calculation, the DG-FETD method is parallelized by using Message Passing Interface (MPI). [ABSTRACT FROM PUBLISHER]

The coaxial two-mirror telescope consists of two mirrors facing each other. Classical two-mirror arrangements are Gregorian and Cassegrain. These systems are usually applied to space telescopes and often have optical baffles to prevent stray light from entering the focal plane. The optical baffles consist of concentric rings suspended between the secondary and the primary mirror. The secondary baffle for a large two-mirror optical system is designed and analyzed in this paper. According to mission of a telescope, the structure should have high stiffness and high reliability and light weight. Compared with invar, aluminum alloy and titanium alloy, carbon fiber composite is currently the best material in terms of weight-to-strength ratio. It also has advantages of high temperature tolerance and low thermal expansion. So carbon fiber composite is chosen as material to meet requirements of the coaxial telescope. In this paper, optimization method based on finite element analysis (FEA) is used for design the secondary baffle. Minimum weight of the baffle is chosen as an objective function. Thicknesses of former tube and vanes are chosen as variables. Analysis results show that the designed secondary baffle has maximum diameter of 180mm, total length of 120mm and weighs 142g. And its fundamental frequency reaches 651Hz. Therefore the baffle has many advantages, such as ultra-light weight, high stiffness and dimensional stability, etc. The optimization method and the baffle design can be helpful to other coaxial telescopes, such as Cassegrain, Gregorian and their subdivisions. [ABSTRACT FROM PUBLISHER]

Sonic Infrared Imaging (SIR) technology is a novel NDE method in NDE family. This technology is capable of detecting surface and subsurface defects in metals, metal alloys, and composites. SIR combines ultrasonic excitation with IR imaging to give a quick detection response in the crack region by observing the temperature change on the structure surface. Nonlinearity phenomena in SIR occur in the coupling between the target and ultrasound transducer, where a single frequency driving excitation source produces sound waves containing multiple frequencies. This nonlinearity is critical in improving the probability of crack detection significantly. In this paper, we will present our study on nonlinearity in SIR with emphasis on the relationship between the frequency of the induced sound waves and their corresponding energy consumption level in the crack vicinity of samples. [ABSTRACT FROM AUTHOR]

This paper deals with the development of a numerical model, based on the Finite Element Method (FEM), for the simulation of Low Velocity Impact (LVI) phenomena on short Glass Fibre Reinforced Polymers (GFRP) plates with two different impact energy levels. In order to assess the reliability of the proposed FE model, the numerical results have been compared to the experimental ones achieved by a tests campaign carried out within such research activity; tests have been performed according to the ASTM D7136 requirement. The overall contact force response in the FE simulations match well with the experimental measurements in terms of both slope and peak. [ABSTRACT FROM AUTHOR]

Various areas related to fixture are already described by renowned authors, but still there is an urgent need to apply all these research works to an industrial application. This paper presents design and development of rotary fixture for machining real industrial component - Flow TEE body of petroleum refinery. Actually HMC is the best solution for performing the required operations, but HMC costs around 12.5 million rupees whereas CNC turning centre costs only about 2.5 million rupees. Here the research work of this paper is proved. A fixture is designed & manufactured, which helps to accomplish required machining operations on CNC turning centre and hence 10 million rupees are saved in installation cost. Methodology for mass balance of rotary fixture developed by investigators mostly act as post-mortem tool; calculating unbalanced mass after fixture is manufactured. In the present work, a pre-mortem tool is developed to predict unbalanced mass well before manufacturing. The present research work also proposes three alternate methods for mass balancing of rotary fixture using Pro/Mechanism. Analytical analysis under dynamic machining is also covered. Fixture not only being designed and mass balanced, but manufactured also; this paper sets the classical example of design for manufacturing. [ABSTRACT FROM AUTHOR]

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This paper presents a quarter-wave longitudinal vibrator which is applied to ultrasonic assisted wire drawing. The characteristic of this vibrator is only driven by an axially polarized sandwich PZT stack, which converts electrical energy into mechanical vibration energy. The transducer and horn were designed at the same side of the nodal section to achieve greater vibration at the front of the horn. The four-terminal network method was used to design the vibrator. The finite element method (FEM) was adopted to verify the above design and used for the further analysis about the vibration performances of this vibrator. The numberial caculation results match well with the simulation results. The simulation indicates that the resonance frequency of the longitudinal vibration is about 19.6188 kHz and the amplitude of longitudinal vibration at the end of the horn is about 11.48 µm. The present work provides a new longitudinal vibrator for ultrasonic wire drawing. [ABSTRACT FROM AUTHOR]

This paper deals with the diagnostics system of power transformers created as parametrical model by means of 3D Finite Element Analysis (FEA). This parametrical model and diagnostics system is used for power transformer 25 MVA and it can be used for all kind of transformers. The following important parameters are investigated from diagnostic point of view: equivalent circuit parameters and capacity for different faults of transformer. On the beginning of investigation these parameters are calculated from transformer design, from measurements and by means of 3D FEA. The results are compared and used for diagnostic database. These results are analyzed annually in accordance with maintenance rules and standards in Slovakia. [ABSTRACT FROM PUBLISHER]

The paper deals with the diagnostics system of power transformers supported by Finite Element Analysis (FEA). This diagnostics system is used for power transformer 25 MVA. The following important parameters are investigated from diagnostic point of view: equivalent circuit parameters, capacity and loss index. On the beginning of investigation these parameters are calculated from transformer design, from measurements and by means of 3D FEA. The results are compared and used for diagnostic database. These results are analyzed annually in accordance with maintenance rules and standards in Slovakia. [ABSTRACT FROM PUBLISHER]

This paper presents a finite element solution for three-dimensional isothermal flow for DC arc furnace where low frequency AC component is added. Electrodes of the furnace are connected with independent supply sources. Current densities, magnetic flux densities, force densities and flow of molten metal are investigated in the case of two different furnace constructions. Methodology for supply source control described in this paper can be used in industrial applications for mixing molten metals or other conductive liquids. [ABSTRACT FROM PUBLISHER]

The use of composite insulators for overhead transmission lines has increased in the past decade. Various designs and models are now available for a wide range of voltages. The 3D Finite Element Analysis electric field distribution of such composite insulators has been of considerable interest due to its differences to ‘conventional’ glass or ceramic insulators. Results of such analysis are now widely available. The present paper presents and analyses the electric field distribution around a composite insulator, which is intended to replace both existing high voltage insulators and the cross-arms of transmission towers. The complex geometry of the composite cross-arm, which includes four separate insulator strings and different shed profiles across these members all connected to a common metallic nose cone, make it difficult to model in any 3D Finite Element Analysis package. The present paper will evaluate the electric fields on such a composite cross-arm, in regards to the areas of high field enhancement. [ABSTRACT FROM PUBLISHER]

This paper describes the mechanical design and analysis of the cryostats for the two cos(2θ) quadrupoles and the cos(θ) dipole. All the magnets are currently being bid for commercial fabrication. The results of finite element analysis for the magnet cryostat helium vessels and outer vacuum chambers which investigate the mechanical integrity under maximum allowable internal working pressure, maximum allowable external working pressure, and cryogenic temperature are discussed. The allowable stress criterion is determined based on the allowable stress philosophy of the ASME codes. The computed cryogenic heat load of the magnets is compared with the allowable cryogenic consumption budget. The presented cool-down time of the magnets was studied under the conditions of a limited supply rate and a controlled temperature differential of 50 K in the magnets. [ABSTRACT FROM AUTHOR]

The work presented in this paper is part of a more extensive study the aim of which is to build a complete simulation of the clinching process and subsequent resistance tests. This paper focuses on finite element analyses -that are performed with the ABAQUS™ code- of the resistance of clinched points to shear test. These analyses are run up to propagation of metal sheet fracture. A simplified procedure is proposed to identify the fracture initiation and propagation models that are used to simulate this failure process. This identification process is based on Lemaitre’s ductile damage model. The numerical simulations of a shear test have been compared to experimental results. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Among the machining errors generated in the peripheral milling the dimensional accuracy and surface roughness play a fundamental role in the quality of the machined component in the automotive and aerospace industry. The inadequacy of the surface roughness and the imprecision of the dimensional accuracy brings to the rejection of the part that causes financial loss and productivity slowdown. In this paper an analysis of the machining errors due to the cutting forces in peripheral milling was performed by means of a numerical model based on the finite element method. The dynamic cutting forces distribution were evaluated for several cutting conditions that varied with the effective rake angle, the axial depth of cut, the radial depth of cut and the feed per tooth per revolution. The model was tested with the cutting forces measured by Yucesan and Altintas in field trials on a titanium alloy. An analytical model furnished by Liu et al. and calibrated with the Yucesan’s results gave a benchmark to the discussion of the results of this paper. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Defects induced in woven textile reinforcements during 3D forming reduce their cured mechanical performance. Numerical modelling is critical to understanding the forming process and the interactions between material, tooling, and process parameters which lead to the formation of these defects. Elastomeric diaphragms utilised in double diaphragm forming experience large deformations and influence the formability of woven textiles. This paper presents a numerical approach to validate the hyperelastic behaviour of an aero-grade silicone diaphragm utilised in double diaphragm forming. Four hyperelastic constitutive models (Neo Hooke, second order Polynomial, second and third order Ogden) are calibrated against uniaxial extension, equibiaxial extension, and planar extension test data with high correlation. The calibrated models are applied to a representative forming experiment with good agreement. The Neo Hookean model was most highly correlated with experiment below 200% strain, whilst the Ogden model shows good correlation across the entire tested deformation range. [ABSTRACT FROM AUTHOR]

Measurement conditions and material properties have a significant impact on the dimensions of a part, especially for polymers parts. Temperature variation causes part deformations that increase the uncertainty of the measurement process. Current industrial tolerances of a few micrometres demand high accurate measurements in non-controlled ambient. Most of polymer parts are manufactured by injection moulding and their inspection is carried out after stabilization, around 200 hours. The overall goal of this work is to reach±5μm in uncertainty measurements a polymer products which is a challenge in today's production and metrology environments. The residual deformations in polymer products at room temperature after injection molding are important when micrometer accuracy needs to be achieved. Numerical modelling can give a valuable insight to what is happening in the polymer during cooling down after injection molding. In order to obtain accurate simulations, accurate inputs to the model are crucial. In reality however, the material and physical properties will have some variations. Although these variations may be small, they can act as a source of uncertainty for the measurement. In this paper, we investigated how big the variation in material and physical properties are allowed in order to reach the 5 μm target on the uncertainty. [ABSTRACT FROM AUTHOR]

Femur bone stress shielding is known to be a significant factor in aseptic loosening or failure of hip replacements. This paper considers the development of a porous stemmed hip implant for children patient in order to reduce the effects of stress shielding and also maintaining acceptably low levels of stress in other areas of prosthesis. By using finite element modeling, the stresses in the proximal femur using porous stem were calculated and analyzed. The developed model is considered safe in terms of mechanical strength. The porous region does not bring significant effect on stress distribution but produces a considerable amount of compressive strain. [ABSTRACT FROM AUTHOR]

Reinforced concrete (RC) slabs without shear reinforcement are commonly used in the existing bridge structures. An ability of RC slabs to distribute the concentrated loads due to the wheel pressure in transverse direction is an important property for their verification. The aim of this paper is to investigate the effect of redistribution of shear forces and bending moments on the load carrying capacity of RC slabs subjected to concentrated loads. Two methods of the assessment are used: simplified analytical formulations and linear finite element analysis (LFEA). The obtained results are consequently compared with the test results taken from three experimental campaigns. The analyses show big differences among the results obtained from the simplified analytical methods that are based on the design equations introduced in the relevant standards. Improved methods, such as LFEA combined with analytical post-processing method, reflect the structural behaviour in a better way and provide more accurate load-bearing capacity prediction of the bridge deck slabs. [ABSTRACT FROM AUTHOR]

Beam-to-column end-plate bolted connections are usually used as moment-resistant connections in steel framed structures. For this joint type, the deformability is governed by the deformation capacity of the column flange and end-plate under tension and elongation of the bolts. All these elements around the beam tension flange form the tension region of the joint, which can be modeled by means of equivalent T-stubs. In this paper a beam-to-column end-plate bolted connection is substituted with a T-stub of appropriate effective length and it is analyzed using the commercially available finite element software ABAQUS. The performance of the model is validated by comparing the behavior of the T-stub from the numerical simulation with the behavior of the connection as a whole. The moment-rotation curve of the T-stub obtained from the numerical simulation is compared with the behavior of the whole extended end-plate connection, obtained by numerical simulation, experimental tests and analytical approach. [ABSTRACT FROM AUTHOR]

The defects exist in the cement grouting process of prestressed corrugated pipe may directly impair the bridge safety. In this paper, sound fields propagation in concrete structures with corrugated pipes and the influence of various different defects are simulated and analyzed using finite element method. The simulation results demonstrate a much complex propagation characteristic due to multiple reflection, refraction and scattering, where the scattering signals caused by metal are very strong, while the signals scattered by an air bubble are weaker. The influence of defect both in time and frequency domain are found through deconvolution treatment. In the time domain, the deconvolution signals correspond to larger defect display a larger head wave amplitude and shorter arrive time than those of smaller defects; in the frequency domain, larger defect also shows a stronger amplitude, lower center frequency and lower cutoff frequency. [ABSTRACT FROM AUTHOR]

This paper reviews the use of finite element analysis to determine the causes of the failure of the compression expansion turbine for the nitric acid plant that occurred at the company (August 2017). After an extensive literature study on the main causes of turbine failure, the researchers conducted a finite element analysis on the material of the turbine blades (Austenitic) and found out that the base metal used for the alloy may have failed to withstand the high temperatures (640°) that the turbine was subjected to. This research is going to help prevent future failure by use of material that can withstand high thermal stresses. [ABSTRACT FROM AUTHOR]

In the following paper results of the investigation of the "Bauschinger effect" are presented. It was done by model which was made in ABAQUS and observed from deep rolling simulation results of residual stresses. Later, comparison of the results are presented by variation of forces and overlapping factor. Deep rolling (DR) is a mechanical surface treatment widely used due to its ability to increase the fatique life of the treated components. The finite element analysis (FEA) is a convenient tool which can be used to model the DR process and facilitate its implementation in to new components. A central aspect in the FE modeling is the material definition and particularly presence of the mechanical phenomenon called "Bauschinger effect". The material used for the simulation was a steel alloy 42CrMoS4 with mass density of 7720 kg/m3, Young Modulus of 210 MPa, Poisson's ratio of 0.28 and plastic hardening type was defined as a kinematic. [ABSTRACT FROM AUTHOR]

In this paper, a new eccentricity compensation method for Switched Reluctance Machines (SRMs) is presented. Eccentricity faults are very common in these machines; nevertheless there are little literatures addressing the control and compensation on this issue. It is theoretically shown that the occurrence and growth of the eccentricity fault change the amplitude of radial forces (RF) exerted on the rotor and accordingly the amplitude of the unbalanced magnetic force (UMF) is increased, these RFs can be controlled to compensate the fault. In this regard, the dependency of RF on variation of number of turns for stator coils and fault level is demonstrated analytically and principle of the new compensation strategy is introduced as well. This strategy is implemented on a SRM utilizing Finite Element Method (FEM). This approach is accomplished through switching among the various arrangements in the number of turns for the coils on the stator poles; hence, UMF is controlled without additional auxiliary coils. [ABSTRACT FROM PUBLISHER]

As per IEC-60034-2-1, 2007, for a rotating electrical machine, the stray loss component increases with the decrease in the size of the machine. This causes a drastic reduction in the machine efficiency, especially in small a.c. motors. Using measures for reducing stray loss will greatly help in improving the efficiency of motors. This paper explores a novel method for reducing the stray loss in totally enclosed fan cooled (TEFC) induction motors. The concept of diamagnetic shielding has been used to reduce the stray loss occurring due to leakage of flux from stator's outer surface. Electromagnetic Analysis based on Finite Element Analysis (FEA) has been used extensively for this study. The effectiveness of the method has been highlighted by analyzing flux plots generated by electromagnetic software, Maxwell. [ABSTRACT FROM PUBLISHER]

The paper presents a few aspects concerning shafts coupling using elastic elements, more precise, with corrugated bellows. The degree of freedom necessary for an accurate coupling is found. The advantages and inconveniences of the presented coupling are presented. As main benefits, the simplicity and relatively reduced costs are highlighted. The major disadvantages mentioned are the infinite degree of freedom of the coupling elements and the occurrence of vibration phenomenon that affects the quality of motion transmission. [ABSTRACT FROM AUTHOR]

Flexible hinges are widely used in micro robotic. Its rigidity directly influences an organization's terminal localization. Its actual structure geometry size cannot satisfy the theoretical analysis completely in a theoretical supposition condition. In this paper, we analyzed the rotation rigidity of half arc flexible hinges in different parameters using finite element software ANSYS. The errors are discovered and compared with theoretical result. An analysis of changes of parameters on the performance of arc flexible hinge was carried out, though the graph of the flexible hinge's parameters and its performance. The key manufacture parameters that affect the performance of arc flexible hinge the most and rules of design are given, which can provide directions of design precision for the flexible hinge. [ABSTRACT FROM PUBLISHER]

Finite element analysis involves the solution of linear systems described by large size sparse matrices. Iterative Krylov methods are well suited for such type of problems. These methods require linear algebra operations, including sparse matrix-vector multiplication which can be computationally expensive for large size matrices. In this paper, we present the best way to perform these operations, in double precision, on Graphics Processing Unit (GPU). Several linear algebra libraries are considered and compared to our proper implementation. These libraries and our proper implementation are then integrated within an iterative Krylov method on the GPU. Numerical experiments done on a set of finite element matrices are presented and illustrate the performance, robustness and accuracy of our proper implementation compared to the existing libraries and its suitability for finite element analysis. Dynamic tuning of the gridification, upon the GPU architecture and the finite element matrix characteristics, is finally applied to faster the sparse matrix-vector multiplication operation. [ABSTRACT FROM PUBLISHER]

It is well known that biomaterials contain quantities of water which is a polar dielectric, yielding polarization under electric field. It may affect the formation of ice crystal. Electric field has been brought into control the formation and growth of ice crystals to improve the efficiency of cryopreservation. This paper describes micro cross-comb electro-freezing chip that can be used in the crystallization experiments of aqueous solutions in the presence of AC electric field. The magnitude and distribution of electric field in micro electro-freezing chip were obtained by using finite element analysis. The result of simulation was quasi-uniform electric field. Furthermore, micro electro-freezing chips combined with microscope were used to observe the ice crystal of aqueous solution under AC electric field. According to the experimental result, the optimal parameters for electro-freezing can be found out. [ABSTRACT FROM PUBLISHER]

This paper is about the analysis and design of a longitudinal piezoelectric vibration exciter, which is required to produce forces that are more than 10N from 100Hz to 2kHz. The device consists of three main parts- the rear plate, driving element and working end. Equivalent Circuit Method (ECM in short) and Finite Element Analysis (FEA in short) are used to choose the material and size of each part. By analyzing the frequency-force spectra of FEA models with different sizes and working loads, the structure of the longitudinal piezoelectric vibration exciter is finally determined. Apart from fulfilling the basic requirement, it can also be effectively used at frequencies more than 2 kHz. [ABSTRACT FROM PUBLISHER]

This paper describes flowing of molten metal in a novel electric arc furnace. Combined AC and DC components are used in the supply system for the furnace. Finite element method is used to investigate the impact of AC component frequency on the flowing of molten metal. [ABSTRACT FROM PUBLISHER]

If not well designed, high voltage composite insulators are prone to ageing and failure due to corona and electric field stress. Particular care is required designing areas where the metal end connections meet the insulator core, otherwise a large electric field enhancement is observed. It is difficult to completely eradicate corona on any insulator, thus manufacturers try and minimise this phenomenon by designing the assembly to increase the corona inception voltage across the end connections and other metallic components. Often this involves introduction of corona rings, especially at the high voltage end of the composite insulator, to manage the magnitude of the electric field. The use of FEA to design corona/grading rings and optimise their position has recently been of great interest. The present paper reviews the use of FEA simulation to design stress relief devices across the high voltage end of a composite insulating cross-arm. Design work has been realised in practice and verified using corona inception measurements and compared to previous FEA results. [ABSTRACT FROM PUBLISHER]

This paper presents a novel numerical approach to solving the inverse dynamics of variable geometry trusses (VGTs) with elastic elements, allowing designers to accurately and efficiently determine motor action requirements, and the time-dependent behavior of the structure. The dynamic equations have been simplified by assuming that movements of the structure are relatively slow, since VGTs are generally used in situations requiring high accuracy. Unlike existing techniques, the formulation is based on simple finite element models. The analysis is based on modal coordinates, and takes place in two stages: first, motor actions are calculated in a model with no actuator stiffness; then small-amplitude, undamped vibrations are obtained in a model that includes actuator stiffness. The method is validated by simulating a three-dimensional VGT. [ABSTRACT FROM AUTHOR]

In this paper, finite element software is used to simulate and analyze ECC beams. With the ratio of waterbinder, fiber content and the content of fly ash as variables, the initial cracking moments, the yield moments, the initial cracking deflections, and the yield deflections of the ECC beams are studied. The results show that the lower the waterbinder ratio is, the better the beam performance is; When the fiber content is 13kg/m3, the mechanical properties of the ECC beams are the lowest, and then strengthen; When the content of fly ash increase, the bending moment of the specimen beam becomes smaller and the deflection tends to increase, however the deflection of the fly ash decreases when the content of fly ash is higher than 1300kg/m3 in the initial cracking. According to the formula of ordinary concrete ultimate load capacity, the formula of yield capacity of ECC beam is deduced. [ABSTRACT FROM AUTHOR]

Impact damage has been identified as a critical form of the defects that constantly threatened the reliability of composite structures, such as those used in the aerospace structures and systems. Low energy impacts can introduce barely visible damage and cause the degradation of structural stiffness, furthermore, the flaws caused by low-velocity impact are so dangerous that they can give rise to the further extended delaminations. In order to improve the reliability and load carrying capacity of composite laminates under low-velocity impact, in this paper, the numerical simulatings and experimental studies on the woven fiber-reinforced composite laminates under low-velocity impact with impact energy 16.7J were discussed. The low velocity impact experiment was carried out through drop-weight system as the reason of inertia effect. A numerical progressive damage model was provided, in which the damages of fiber, matrix and interlamina were considered by VUMT subroutine in ABAQUS, to determine the damage modes. The Hashin failure criteria were improved to cover the failure modes of fiber failure in the directions of warp/weft and delaminations. The results of Finite Element Analysis (FEA) were compared with the experimental results of nondestructive examination including the results of ultrasonic C-scan, cross-section stereomicroscope and contact force - time history curves. It is found that the response of laminates under low-velocity impact could be divided into stages with different damage. Before the max-deformation of the laminates occurring, the matrix cracking, fiber breakage and delaminations were simulated during the impactor dropping. During the releasing and rebounding period, matrix cracking and delaminations areas kept increasing in the laminates because of the stress releasing of laminates. Finally, the simulating results showed the good agreements with the results of experiment. [ABSTRACT FROM AUTHOR]

Hydroelectric power plants (HPP) are one of the most used form of energy generation plants across the world and their development assures also the developing of other industries and economic sectors. The dams of a HPP are playing a major role in preventing floods and multiple use of the water (water supply, agriculture, etc). HPPs are playing a crucial role in the supply of grid system services while providing frequency and voltage balancing services. Their capabilities to adjust the generated power and operate at partial loads, to accumulate the hydraulic energy in reservoirs and to deliver energy with fast response time, recommends them to be actively involved in the grid services required to assure the continuity and safety in operation. However, not every HPP is most adequate to provide all type of energy balancing services due to their fundamental design. A derivation HPP designed with a higher value of the installed coefficient, will assure operation at peak region of the energy demand curve generating few hours per day and is mostly used to provide grid services rather than a run-of-river HPP. The main services provided are voltage and frequency regulation but also reactive power balancing which means that the generator unit is operating in compensatory regime. This paper presents the results obtained by researchers during a complete fatigue analysis study of the mechanical elements of a HPP equipped with a 55 MW Francis turbine. The analysis was done in order to determine the remaining lifetime of the main equipment, in order to develop the maintenance program if case. [ABSTRACT FROM AUTHOR]

The objective of this paper is to compare the shear and peel stress distributions in the single lap joints obtained using analytical model with those obtained using numerical analysis. The Zhao's closed form solution that includes the bending moment effect was used as an analytical model. In the numerical analysis, two dimensional finite element model with plane strain assumption was used. Analyses were performed for stiff and ductile adhesive types both analytically and numerically. In addition, a comparison of peak shear and peak peel stress values was carried out on the basis of percentage error. The results show that both analytical and numerical analyses were in very close agreement. [ABSTRACT FROM AUTHOR]

A novel effective geometric modeling approach for finite element mesh generation is proposed in this paper based on finite element analysis software (FEAS). The grid matching problem of discontinuous dielectric media is dealt with from the perspective of geometric modeling. Examples show that the presented techniques are simple and accurate, and thus they can be used for modeling. [ABSTRACT FROM PUBLISHER]

The obligatory demands on the belt conveyor braking system under a wide variety of operating conditions are high and diverse. Improvements in the operating conditions of conveyor belt systems are made more difficult because braking is deterministic by nature. The performance of the belt conveyor brake mainly affected the role of the braking system because its performance was due to complex inter-related phenomena in contacts of different friction pairs. The main purpose of this study is an investigation with ANSYS software code to test the behavior of a disk under the same static and geometry profile for a solid conveyor disc brake during continuous braking. This paper examines the behavior of disk material braking efficiency under thermal and imposed heat condition. Finite element method (FEM) were used to perform the analysis on four materials of brake disc. The study will focus on different performances on heat flow, the distribution of temperature and disk damage via deformation. Comparison of the results achieved with those of the technical literature and simulation, have been found satisfactory. [ABSTRACT FROM AUTHOR]

Bulk molding compound (BMC) is one of the important composite materials with various engineering applications. BMC is a thermoset plastic resin blend of various inert fillers, fiber reinforcements, catalysts, stabilizers and pigments that form a viscous, molding compound. Depending on the end-use application, bulk molding compounds are formulated to achieve close dimensional control, flame and scratch resistance, electrical insulation, corrosion and stain resistance, superior mechanical properties, low shrink and color stability. Its excellent flow characteristics, dielectric properties, and flame resistance make this thermoset material wellsuited to a wide variety of applications requiring precision in detail and dimensions as well as high performance. When a BMC is used for these purposes, the rheological behavior and properties of the BMC is the main concern. In this paper, finite element analysis of rheological properties of bulk molding composite material was studied. For this purpose, standard samples of composite material were obtained by means of uniaxial hot pressing. 3 point flexural tests were then carried out by using a universal testing machine. Finite element analyses were then performed with defined material properties within a specific constitutive material behavior. Experimental and numerical results were then compared. Good correlation between the numerical simulation and the experimental results was obtained. It was expected with this study that effects of various process parameters and boundary conditions on the rheological behavior of bulk molding compounds could be determined by means of numerical analysis without detailed experimental work. [ABSTRACT FROM AUTHOR]

This paper provides simulation practitioners and consumers with a grounding in how discrete-event simulation software works. Topics include discrete-event systems; entities, resources, control elements and operations; simulation runs; entity states; entity lists; and their management. The implementations of these generic ideas in AutoMod, SLX, ExtendSim, and Simio are described. The paper concludes with several examples of “why it matters” for modelers to know how their simulation software works, including discussion of AutoMod, SLX, ExtendSim, Simio, Arena, ProModel, and GPSS/H. [ABSTRACT FROM PUBLISHER]