Top PDF Numerical and Experimental Stress Analysis of a Composite Leaf Spring

Numerical and Experimental Stress Analysis of a Composite Leaf Spring

Numerical and Experimental Stress Analysis of a Composite Leaf Spring

Abstract - Automobile sector is always focusing on enhancing level of comfort, fuel economy, customer satisfaction and safety. Vehicle weight reduction increases the overall fuel efficiency. Use of composite materials has made it possible to reduce the weight of the vehicle, without reduction in load carrying capacity. Now a day's manufacturers and researchers are trying to replace conventional material parts with composites. The composite materials have more elastic strain energy storage capacity and high strength to weight ratio as compared to steel. This paper is related to Numerical and experimental strength analysis of suspension leaf springs for a light motor vehicle made of composite materials. Two materials Glass Fiber Reinforced Plastic (GFRP) and Carbon Fiber Reinforced Plastic (CFRP) are selected for manufacturing of leaf spring. The strength of these composite depends on angle orientation, volume to weight ratio of reinforcement and length to depth ratio of fiber. In this work two leaf springs made of GFRP and a sandwich of CFRP and GFRP are developed. Numerical and experimental static stress analyses are carried out for these two springs. These results are compared with analytical results of conventional metal spring. The comparison shows that composite material springs have compatible strength to withstand load. Comparative results for weight, cost and deformation are presented at the end of the paper.
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Rev. IBRACON Estrut. Mater.  vol.6 número2

Rev. IBRACON Estrut. Mater. vol.6 número2

The use of composite materials based on polymeric resins and iber as strengthening in concrete structures has been widely used. The use of carbon iber reinforced polymers or other synthetic ibers is consolidated by its excellent characteristics, such as high strength, low weight, corro- sion resistance, etc. This material in the form of sheets or laminates is bonded to the concrete substrate with epoxy-based adhesives. Although epoxy has proven to have excellent bonding and resistance performance, it has some disadvantages, such as low permeability, poor thermal compatibility with the base concrete, poor ire resistance, etc. Cement-based composite systems consisting of FRPs and a cementitious bonding agent can be used to prevent some of these problems. This study presents the numerical analysis, using a non-linear inite element model, of the structural behavior of reinforced concrete beams externally reinforced with a composite material made of high-strength synthetic iber mesh and cementitious mortar. The numerical results were compared with experimental results reported in international journals, demonstrating the ef- iciency of the strengthening technique and the numerical model capacity.
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Numerical and Experimental Analysis of Ballistic Armors

Numerical and Experimental Analysis of Ballistic Armors

For composites the result was also acceptable in comparison with the experi- mental results, i.e. a single composite panel was completely perforated, while in the second composite panel prevents the projectile from passing through them. In the latter situation (Aluminum and Composite Panels), the projectile does not completely perforate the target. However, elements were eliminated from the aluminum mesh, that was not observed in the real fire experiment which only shows a slight deformation.

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Stress wave propagation in thin long-fiber carbon/epoxy composite panel. Numerical and experimental solutions

Stress wave propagation in thin long-fiber carbon/epoxy composite panel. Numerical and experimental solutions

measured from the loaded edge). They were loaded by in-plane impact of steel sphere. The impact area was on the edge, exactly 150 mm from top left corners corner of the panels. The loading force was approximated by a time dependent function. Its shape was obtained from three dimensional contact analysis, which was performed on smaller area of panel. The function was used in further plane stress analysis of the whole panels. The comparison of the numerical and experimental results was executed. An attempt at determination of velocity of propagation of Rayleigh waves on the loaded edge was performed and the results are discussed in the paper. Further directions of the research are proposed.
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Dynamic Analysis of Numerical Mesoscale Models of Composite Materials

Dynamic Analysis of Numerical Mesoscale Models of Composite Materials

After the validation of the implementation of cohesive properties and the combined failure criterion, six models of one ply with 0°/90°, 15°/75° and 30°/60° arrangements and two models for the ten plies and twenty-six plies test specimens with a 0°/90° arrangement (aiming the comparison of the test specimen’s behavior when subjected to external loads) where tested, with all the features previously tested and described implemented. As results taken from the force-displacement curves show, both methods lead to very similar pick forces right before failure of the elements. As for the behavior, only the models of one ply with 15°/75° and 30°/60° arrangement show element failure occurring at a different area. Even if some parameters might need to be adjusted, results show a very good correlation with the ones obtained by Mangualde, leading to the validation of the developed models. As for the compressive test of the twenty-six plies, results show that constraining the top surface of the test specimen influences the stress necessary for element failure. Finally, when comparing with the data obtained by Crespo [2], a significant difference in the results can be observed, leading to the conclusion that more tests must be carried out in order to determine which model is at fault and converge the results with the experimental tests presented in Crespo’s dissertation [2].
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Experimental Investigation on Laminated Composite Leaf springs Subjected to Cyclic Loading

Experimental Investigation on Laminated Composite Leaf springs Subjected to Cyclic Loading

An author showed that increase in stiffness , natural frequency and reduced in stress , weight in composite leaf spring[1-5].Researchers have presented a genetic algorithms for optimal design of composite leaf spring .They found that huge weight was reduced in existing spring weight on optimization using genetic algorithms[6].An author described the design and manufactured of a functional composite spring for a solar powered light vehicle .Many testing was carried out during actual driving condition. They found that by placing of rubber pads on inside surfaces of the blades to cushion bottoming of the spring. It will reduces the impact load transferred to the chasis while suspension reaches the full deflection [7].For the freight rail application the researchers shows the paper in the design evolution process of a composite leaf spring. They described the three design of eye end attachment for a composite leaf spring [8].Author demonstrated for the application of light and heavy trucks composites elliptical spring meet the requirements with substantial weight saving. Adequate works have been carried out in the past two decades on design ,analysis and optimisation on composite leaf spring[9-11]. C.Subramanian et al fabricated the discontinuous fiber reinforced thermoplastic composite leaf spring by injection moulding and investigated the short term flexural creep performance.HRZ model was used for the creep performance evaluation. Results shows that HRZ model was found to be useful for predicting the short term creep performance[12]
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Numerical and experimental analysis of yield loads in welded gap hollow YT-joint

Numerical and experimental analysis of yield loads in welded gap hollow YT-joint

This paper presents an analytical, experimental, and numer- ical analysis of plain steel, circular hollow sections welded into a YT joint. The overall behavior and failure of the joint are characterized under axial compression of the lap brace. There are two joint failure modes: plastic failure of the chord face and local buckling of the chord walls. Numerical finite element models agree with the experimental data, in terms of principal stress near the joint intersection, with an accuracy of around 10%. The finite element model thus proves to be reliable and accurate, and will be used in future parametric studies.
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Rev. IBRACON Estrut. Mater.  vol.3 número3

Rev. IBRACON Estrut. Mater. vol.3 número3

In this paper is discussed the inluence of the end conditions in composite cold-formed steel box section and concrete over masonry in ire situ- ation. The software ANSYS was used for numerical simulation of the composite beam. The end conditions are considered as ixed or pinned and axial restrained at the ends. Initially, numerical thermal analysis to determine the ield of temperatures in the steel proile and the slab under ISO-ire are carried out. The heat lux between steel, concrete slab and masonry are considered. The structural analysis is carried through for evaluating the performance of the composite beam in ire. Both geometric and materials nonlinearities, as well as the variation of the stress-strain diagram of the materials in function of the temperature are considered. Finally, comparisons between the behavior of beams with ixed ends and pinned ends are shown as well as the reduction factors with the time of exposition to the ire are determined.
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Double-Leaf Infill Masonry Walls Cyclic In-Plane Behaviour: Experimental and Numerical Investigation

Double-Leaf Infill Masonry Walls Cyclic In-Plane Behaviour: Experimental and Numerical Investigation

The presented simplified macro-model can be applied in OpenSees [42] with the association of the available OpenSees materials, sections and elements commands. The infill model must be composed by four Elastic Beam Columns for the diagonal elements and by one nonlinear Beam Column element for the central element. The Pinching4 uniaxial material model was used to represent the hysteretic behavior of the infill panel and was attributed for the central element. This uniaxial material is used to construct a material that represents a 'pinched' load-deformation response and exhibits degradation under cyclic loading. Cyclic degradation of strength and stiffness occurs in three ways: unloading stiffness degradation, reloading stiffness degradation, strength degradation. Further details regarding the in-plane calibration of the infills behaviour can be found in [29, 43, 44]. Furtado et al [44] demonstrated that this numerical model approach represents well global response and energy dissipation of the infill panel when subjected to horizontal loadings. This model is also able to consider the out-of-plane of the infill panel during a non-linear analysis and in particular the interaction between the in-plane and the out-of-plane behaviour of the panel [29].
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Stress analysis in strain hardening two-layer composite tubes subject to cyclic loading of internal pressure

Stress analysis in strain hardening two-layer composite tubes subject to cyclic loading of internal pressure

In the present work, we extend the internally pressurized two-layer composite tube problem to a cyclically loaded two-layer tube in the elastic and elastic-plastic stress states. A detailed analysis is performed for these tubes under one cycle of loading, unloading, and reloading of internal pressure. This loading cycle under consideration demonstrates an autofrettage process in which a residual stress field is formed inside the tube assembly. In the liter- ature, there are few studies on the cyclic behavior of pressurized tubes. Mahbadi and Eslami [32] studied the cyclic loading behavior of single-layer thick-walled tubes under different types of loading including internal pressure and they used a numerical iterative method in their study. Megahed and Abbas [33] studied the influence of reverse yield- ing on the residual stresses that developed after autofrettage of a single-layer tube. Darijani, Kalgarnovin and Naghd- abadi [34] obtained closed-form solutions of the internally pressurized elastoplastic tube problem in which forward and reversed loading is considered. In contrast to those studies, in our work two-layer composite thick-walled tubes are analyzed in which the locations of the yielding along the tube assembly depend on the tube dimensions. The so- lutions obtained in this study may be used in the analysis and design of the two-layer tube assemblies under internal pressure. In addition, the results of this analytical work may be used as benchmark problems for numerical solutions. As mentioned above, the geometry considered here consists of two tightly fitted concentric tubes. A long tube of inner radius a and outer radius b is placed in a tube of the same length and of inner radius b and outer radius c. The assembly is then constrained axially and at this stage it is stress-free. As the internal pressure is applied, stresses are formed in both of the tubes and increase in magnitude with increasing pressures. Depending on the tube dimensions, the yielding commences at the inner surface, at the interface, or at both locations at a critical value of pressure P = P e .
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Critical review of research paper for analysis of multi leaf spring

Critical review of research paper for analysis of multi leaf spring

C.K. Clarke and G.E. Borowski [2] discussed the determination of the point of failure during an accident. Finite- element stress analysis is used to study the existence of tensile stresses at the location of the fracture. A finite- element analysis is carried in finite-element code ALGOR is conducted on the spring eye stress conditions in order to examine the transverse stresses. Residual-strength calculations are made with longitudinal forces. Reduction in strength produced by the old OD crack is also estimated based on published stress-intensity data.
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PERFORMANCE COMPARISON OF CONVENTIONAL AND COMPOSITE LEAF SPRING

PERFORMANCE COMPARISON OF CONVENTIONAL AND COMPOSITE LEAF SPRING

ANSYS is engineering simulation software used for general purpose finite element analysis and for numerically solving mechanical problems. Here ANSYS 11.0 is used for analysing the performance of conventional and composite leaf spring. Leaf spring is modelled in Unigraphics NX4 software and it is imported in ANSYS 11.0. The conventional steel leaf spring and the composite leaf spring were analysed under similar conditions using ANSYS software and the results are presented.
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Analysis of quality and cost of FeSiMg treatment master alloy vs. cored wire in production of ductile cast iron

Analysis of quality and cost of FeSiMg treatment master alloy vs. cored wire in production of ductile cast iron

Another important aspect of this nodularising treatment is without any doubt the very encouraging cost of the nodulariser, and therefore the aim of this study has been an assessment of the cost of the FeSiMg5% as compared with the nodularisers used in the form of cored wire.

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A Strategic Analysis of Search Engine Advertising in Web  based-commerce

A Strategic Analysis of Search Engine Advertising in Web based-commerce

Online Advertising Industry is one of the most promising revenue generating Industry. With the popularity of Web as information hub and evolution of Online Business Industry Search Engine have emerged as a most popular Advertising vehicle. Search Advertising Strategies have also captured mind of Indian advertisers and are getting popular in Indian Industry. The important reason behind its popularity is that it is a contextual based advertising and it has revenue generating options for the websites which host their ads. However, Search Engine faces leadership challenge in restricting spamming activities. Much research is required to combat such unethical practices that have adversarial affect on Online Business Industry. While analyzing the role of Search Engine in Indian business industry it has been observed that India has not mined this valuable resource completely. The basic reason is unawareness among the population. According to E- marketer daily (2005) Internet use is still uncommon in India. Many consumers do not use Internet and are dependent on traditional methods. India currently has an Internet penetration rate of less than 5% despite the existence of millions of Web users in its cities. This is the major hurdle to the use of Search Engine. To score high in Online Business Search Engine is the best medium and India needs to learn mining this valuable tool completely to get an edge in global Online Industry.
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Some methods for sensitivity analysis of systems / networks

Some methods for sensitivity analysis of systems / networks

A network may considerably change with certain nodes, links, flows, or parameters. To find the most important nodes, links, or other parameters to determine network structure or performance is of significant. Sensitivity analysis is originated from systems science. It explores the relationship between parametric change and systematic output, and is used to find important parameters in the system model. In principle, the sensitivity analysis used in systems science can also be extended to network analysis in which the model output means network output, network stability, network flow, network structure, or other indices, and model input means network nodes, network links, network parameters, etc. In present article, some methods for sensitivity analysis of systems / networks are described in detail.
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	Renal Metastasis of a Malignant Myopericytoma: A Case Report and Review of Literature

Renal Metastasis of a Malignant Myopericytoma: A Case Report and Review of Literature

In July 2015, the patient was referred to the department of internal medicine by her family doctor with weight loss of 8 kg, persistent fatigue, and pain in the right hypochondriac region. There were no urinary symptoms. Clinical examination revealed tenderness in the right hypochondriac region, and ultrasonography showed a mass on the upper pole of the right kidney. A computed tomography (CT) scan of the abdomen revealed a voluminous tumour of 8.2 cm in the upper pole of the right kidney. The tumour showed irregular contrast captation and was assessed as a malignant solid renal tumour, presumably renal cell carcinoma. No pathologically enlarged retroperitoneal nodes were seen (Figure 1A and 1B). A CT image of the thorax showed no abnormalities. A radical right nephrectomy was performed with an uncomplicated postoperative course.
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Method of Obtaining a Composite Material Based on Small-Dispersed Particles

Method of Obtaining a Composite Material Based on Small-Dispersed Particles

are used in radiotherapy. In such therapy the dispersion of particles plays an important role. Therefore the pro- duction of composite materials based on small-dispersed or monodisperse particles is actual task for many appli- cation, not only for medicine, due to their more uniform properties (size and/or weight of the particle, surface area, surface chemistry, chemical composition, surface activation duration agents, etc.). In this work a simple method of obtaining a composite material based on small-dispersed particles is considered.
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STRUCTURAL ANALYSIS AND CONTROL OF VIBRATING HOPPERS FOR HARVESTED GRAPES IN A WINE CELLAR: A CASE STUDY

STRUCTURAL ANALYSIS AND CONTROL OF VIBRATING HOPPERS FOR HARVESTED GRAPES IN A WINE CELLAR: A CASE STUDY

The large vibrating hoppers of the winery can operate at several discrete frequencies by controlling the rotational speed of the motors while the excitation amplitude can be regulated by acting on the relative position of two eccentric masses inserted in the motors. Preliminary vibrational data has revealed the occurence of large amplitude vibratory responses of the slab for several operating speeds, the slab being driven to resonance phenomenom in the frequency range from 7 to 20 Hz. Among the technically applicable solutions, one simple approach to the problem would consist in changing the excitation frequencies as initially proposed by the hopper manufacters, so that the operating frequencies does not overlap with the modal frequencies of the structure. Other possible approach could be to alter the modal behaviour of the structure by structural modifications [2]. However, as already mentioned, the first solution is not sustainable for the winery since the hoppers operate optimally for specific motor speed while architects would certainly not give their permission for significant changes in the design and spatial options of their original plans. Furthermore, altering the modes of such a large structure would remain very challenging. TMDs could also be an efficient solution if only a single mode of the slab would become unstable. However, since resonance occurs at different rotational speed of the motor, this would imply the design and delicate tuning of several TMDs. The implementation of active control solutions [3] could also be attempted to adjust the operation of the control device. They can actually better regulate the dynamics response of the system than passive solutions but it is worth pointing that the practical feasibility of this modern control approach, using control transducers and signal processing techniques, could be delicate in such operating environment besides its rather complexity and expensive cost. It finally remains one common solution to takle efficiently the problem: isolate the machinery from the fondation by elastic decoupling [4].
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Rev. Esc. Minas  vol.67 número3

Rev. Esc. Minas vol.67 número3

A shear connector, developed to be applied to a composite beam whose steel proile is a thin-walled box proile, displayed much greater lexibility than the con- ventional welded shear connector, leading to particular issues in the composite beam behaviour. One of these issues is the role played by friction at the interface between the steel proile and the slab which, under particular circumstances, may be relevant for serviceability limit states and also for ultimate limit states. The Brazilian and Ameri- can Standards do not yet recognize the friction contribution in the behaviour of com- posite beams, though they recognize this contribution in composite slabs. This paper presents the experimental tests carried out with and without friction contribution on simple supported composite beams with lexible connectors and the numerical models developed to simulate the behaviour of the tested beams. The experimental tests re- vealed signiicant increases in strength and stiffness of the composite beam due to fric- tion contribution and the comparisons between numerical and experimental results displayed good correlations.
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Lat. Am. j. solids struct.  vol.11 número2

Lat. Am. j. solids struct. vol.11 número2

A highly important, and at the same time complex problem is the achievement of the assumed ac- curacy of machining and operational reliability of low-rigidity shafts. Such shafts are elements of many assemblies of various machines and devices, and find applications in, among others, aerospace industry, precision mechanics, tool-making industry (special tools), automotive industry. They are characterised by disproportion in overall dimensions and low rigidity in specific sections and direc- tions. Stringent requirements are also applied in terms of the geometric shape, mutual positioning of surfaces, linear dimensions and quality of surface finish.
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