Academic literature on the topic 'Polymer modelling usingy'
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Journal articles on the topic "Polymer modelling usingy"
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Saadatfar, M., and A. Soleimani. "Simulation of Spherical Nanoindentation of Nanocomposites Using FEM." Advanced Materials Research 403-408 (November 2011): 1188–91. http://dx.doi.org/10.4028/www.scientific.net/amr.403-408.1188.
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The study of polymer/clay nanocomposites has attracted major research and commercial interests due to their superior mechanical and thermal properties to those of the neat polymers. The present work is to modelling the spherical nanoindentation of exfoliated polymer /clay nanocomposite that has nonlinear elastic behavior using numerical simulation. A two dimensional simulation is done and the effect of friction coefficient and indenter radius on load-displacement curve is investigated. It is observed that the simulation results of nanoindentation do not depend on the friction coefficient of indenter and specimen significantly.
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Hoang, Mai Quyen, Thi Thu Nga Vu, Manh Quan Nguyen, and Severine Le Roy. "Modelling the conduction mechanisms in low density polyethylene material using finite element method." Ministry of Science and Technology, Vietnam 63, no. 1 (January 30, 2021): 27–33. http://dx.doi.org/10.31276/vjst.63(1).27-33.
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Polymers used as insulating materials are increasingly popular in many different fields. In electrical engineering - electronics, polymers are used in high-voltage transmission cables, capacitors, transformers, or as part of an embedded system in the IGBT module thanks to its superior thermal and electrical insulation properties. One of the disadvantages of polymers is the possible accumulation of space charge in the material volume for a long time, leading to an increase in the electric field compared to the original design value. Charge transport models in polymer materials have been increasingly developed to predict the conduction mechanisms under thermal-electrical stress. In this study, from a finite volume method (FVM), the authors developed a charge transport model in low density polyethylene (LDPE) based on the finite element method (FEM). The simulation results of this model are also compared to experimental results and to the FVM model under different electric fields for LDPE.
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Raje, Vishvesh, Siddhant Palekar, Sabrina Banella, and Ketan Patel. "Tunable Drug Release from Fused Deposition Modelling (FDM) 3D-Printed Tablets Fabricated Using a Novel Extrudable Polymer." Pharmaceutics 14, no. 10 (October 14, 2022): 2192. http://dx.doi.org/10.3390/pharmaceutics14102192.
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Three-dimensional (3D) printing is proving to be a pivotal technology for developing personalized dosage forms with bench to bedside feasibility. Fused deposition modelling (FDM) 3D printing has emerged as the most used technique wherein molten drug-loaded polymer filaments are deposited layer-by-layer to fabricate a predefined shape and internal geometry. However, for precise FDM 3D printing, it is imperative for the filaments to have peculiar mechanical/physicochemical properties, which the majority of the FDA/GRAS approved polymers lack. In the current study, a novel water-soluble polymer, Poly(2-ethyl-tetra-oxazoline) [PETOx] has been investigated as an extrudable and printable polymer with two different types of drug molecule—dextromethorphan hydrobromide (DXM) and hydrochlorothiazide (HCTZ). Hot-stage microscopy experiments of drug:polymer (1:1 w/w) and filaments were carried out at 25–275 °C. HCTZ-loaded filament showed higher toughness of 17 ± 3.25 × 106 J/m3 compared with DXM and drug-free filament. Moisture sorption and flexural analysis was performed to understand the correlation of mechanical properties and storage humidity to printability. Varying the number of outer perimeters of each layer (shell number) was observed to affect the drug release pattern from the printlets. The DXM one-shell printlet showed >80%, whereas the DXM five-shell printlet showed >60% of the drug release within 60 min. PETOx could prove to be a high-performance and versatile 3D printable polymer.
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Marti, Julio, Jimena de la Vega, De-Yi Wang, and Eugenio Oñate. "Numerical Simulation of Flame Retardant Polymers Using a Combined Eulerian–Lagrangian Finite Element Formulation." Applied Sciences 11, no. 13 (June 26, 2021): 5952. http://dx.doi.org/10.3390/app11135952.
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Many polymer-made objects show a trend of melting and dripping in fire, a behavior that may be modified by adding flame retardants (FRs). These affect materials properties, e.g., heat absorption and viscosity. In this paper, the effect of a flame retardant on the fire behavior of polymers in the UL 94 scenario is studied. This goal is achieved essentially by applying a new computational strategy that combines the particle finite element method for the polymer with an Eulerian formulation for air. The sample selected is a polypropylene (PP) with magnesium hydroxide at 30 wt.%. For modelling, values of density, conductivity, specific heat, viscosity, and Arrhenius coefficients are obtained from different literature sources, and experimental characterization is performed. However, to alleviate the missing viscosity at a high temperature, three viscosity curves are introduced on the basis of the viscosity curve provided by NIST and the images of the test. In the experiment, we burn the specimen under the UL 94 condition, recording the process and measuring the temperature evolution by means of three thermocouples. The UL 94 test is solved, validating the methodology and quantifying the effect of FR on the dripping behavior. The numerical results prove that well-adjusted viscosity is crucial to achieving good agreement between the experimental and numerical results in terms of the shape of the polymer and the temperature evolution inside the polymer.
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Зиле, Э., Д. Зеленякене, and A. Анискевич. "Определение характеристик изделий из полимолочной кислоты, изготовленных методом моделирования наплавления." Механика композитных материалов 58, no. 2 (2022): 241–56. http://dx.doi.org/10.22364/mkm.58.2.02.
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Работа посвящена изучению механического поведения материала на основе полимолочной кислоты (ПМК), изготовленного методом моделирования наплавления. Влияние мезоструктуры на макромасштабные механические свойства материала характеризовали степенью пористости. Экспериментально установлена зависимость продольных и поперечных механических свойств от пористости. Показано, что в силу кристаллизации после плавления и экструдирования свойства одиночного волокна из ПМК со временем возрастают. Полученные результаты показывают, что классическая теория слоистых композитов и критерий разрушения Цая–Хилла позволяют предсказать модуль упругости и прочность материалов из ПМК, изготовленных с помощью 3D печати.
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Kotoul, Michal, Petr Skalka, and Ivo Dlouhy. "Crack Bridging Modelling in Bioglass® Based Scaffolds Using Gradient Elasticity Theory." Key Engineering Materials 665 (September 2015): 105–8. http://dx.doi.org/10.4028/www.scientific.net/kem.665.105.
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The paper deals with crack bridging modelling in Bioglass® based scaffolds due the presence of a special polymer coating. This includes a careful identification of bridging mechanism by polymer ligaments, selection of a suitable bridging model and its implementation into the gradient elasticity model of crack.
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Satyanarayana, K. C., J. Abildskov, R. Gani, G. Tsolou, and V. G. Mavrantzas. "Computer aided polymer design using multi-scale modelling." Brazilian Journal of Chemical Engineering 27, no. 3 (September 2010): 369–80. http://dx.doi.org/10.1590/s0104-66322010000300002.
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Salifu, Smith, and Peter Apata Olubambi. "Thermomechanical properties prediction of wood-flour reinforced polymer composites using representative volume element (RVE)." MATEC Web of Conferences 370 (2022): 03002. http://dx.doi.org/10.1051/matecconf/202237003002.
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The accurate prediction of the thermomechanical properties of newly developed polymer composites is important in the determination of their possible areas of application. In this study, a 3D model of representative volume element (RVE) with different wood flour weight ratios (5, 10, 15, 20, 25 and 30 %) was used to develop wood flour polymer composites. Micromechanical material modelling software (Digimat) was used in conjunction with finite element analysis software (Abaqus) to develop the polymer composites and to determine their thermomechanical properties (modulus of elasticity, Poisson’s ratio, thermal conductivity, density, and hardness). The hardness, tensile strength and modulus of elasticity increase with an increase in the wt.% of wood flour, while the Poisson ratio, thermal conductivity and density decrease with an increase in the wt.% of wood flour. Also, the predicted thermomechanical properties using the micromechanical material modelling software (RVE) follow the same trend as those found in the literature.
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Amir, Shahizat, Mohamed Nor Sabirin, and Siti Aishah Hashim Ali. "Using Polymer Electrolyte Membranes as Media to Culture Fractals: A Simulation Study." Advanced Materials Research 93-94 (January 2010): 35–38. http://dx.doi.org/10.4028/www.scientific.net/amr.93-94.35.
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In the authors' laboratory, fern-like fractals have been cultured in polymer electrolyte membranes of polyethylene oxide (PEO) doped with ammonium iodide (NH4I). The simulation study was then carried out utilizing the Diffusion Limited Aggregation (DLA) based on random motion of aggregating particles modelling technique. The fractal dimension values and the forms of the simulated fractals are comparable to those observed in the PEO polymer membranes. These indicate that the simulation using the DLA model done in this study has resulted outputs that are in abidance with the original fractals cultured in the polymer membranes.
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Dutt, J. K., and H. Roy. "Viscoelastic modelling of rotor—shaft systems using an operator-based approach." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 225, no. 1 (June 11, 2010): 73–87. http://dx.doi.org/10.1243/09544062jmes2064.
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Damping exists in every material in varying degrees, so materials in general are viscoelastic in nature. Energy storage, as well as dissipation in varying degrees, accompanies every time-varying deformation, with the effect that stress and strain in a material get out of phase. This work presents the development of equations of motion of a rotor—shaft system with a viscoelastic rotor after discretizing the system into finite elements. Subsequently, these equations are used to study the dynamics of the rotor—shaft system in terms of stability limit of spin speed and time response of a disc as a result of unbalance. The primary inspiration for a viscoelastic model arises from the need to capture the influence of broad band spectral behaviour of rotor—shaft materials, primarily polymers and polymer composites, which are principally the materials of light rotors, on the dynamics of rotor—shaft system. For this, the material constitutive relationship has been represented by a differential time operator. Use of operators enables one to consider general linear viscoelastic behaviours, represented in the time domain by multi-element (three, four, or higher elements) spring—dashpot models or internal variable models, for which, in general, instantaneous stress and its derivatives are proportional to instantaneous strain and its derivatives. Again such representation is fairly generic, in a sense that the operator may be suitably chosen according to the material model to obtain the equations of motion of a rotor—shaft system. The equations so developed may be easily used to find the stability limit speed of a rotor—shaft system as well as the time response when the rotor—shaft system is subjected to any dynamic forcing function.
Dissertations / Theses on the topic "Polymer modelling usingy"
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Godat, Ahmed. "Finite element modelling of externally shear-strengthened beams using fibre reinforced polymers." Thèse, Université de Sherbrooke, 2008. http://savoirs.usherbrooke.ca/handle/11143/1825.
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The need for structural rehabilitation of concrete structures all over the world is well known. A great amount of research is going on in this field. The use of fibre reinforced polymer (FRP) plate bonding has been shown to be a competitive solution regarding both the structural performance and the economical aspects. Shear strengthening of reinforced concrete beams is required when the beam is deficient in shear, or when its shear capacity falls below its flexural capacity after flexural strengthening. An accepted technique for the shear strengthening of reinforced concrete beams is to provide an additional FRP web reinforcement in the form of externally bonded FRP sheets. Over the last few years, a considerable amount of research has been conducted on shear strengthening with FRP composites and that has led to a better understanding of the behaviour. Hence, many design equations have been proposed to design shear-strengthened beams. Most of the parameters that control the behaviour of shear-strengthened beams have been addressed. However, the design equations describing the behaviour of shear-strengthened beams are not sufficient to properly evaluate the shear contribution of the FRP composites. This might be attributed to the absence of an accurate numerical model, which is more economical than the experimental tests, to capture the complexities of shear-strengthened beams and to lead to a better understanding of the failure mechanisms. Limited finite element analyses have been carried out on FRP shear-strengthened beams. As a contribution to fill this need, a versatile numerical model is developed in this study to predict the response of reinforced concrete beams strengthened in shear with bonded FRP composites, with a particular emphasis on the interfacial behaviour and debonding phenomena. This research consists of three phases. They are: (1) the development of a reliable numerical model that can capture the real behaviour of FRP shear-strengthened beams; (2) the use of the proposed numerical model to verify various cases having different strengthening configurations: beams with vertical and inclined side-bonded FRP sheets, the U-wrap scheme, as well as anchored FRP sheets and; (3) a parametric study conducted to identify design variables that have the greatest influence on the behaviour of shear-strengthened beams such as the steel stirrup reinforcement ratio, concrete compressive strength, FRP elastic modulus, FRP thickness, and ratio between FRP width to beam width. The proposed numerical model is validated against published experimental results. The predicted results are shown to compare very well with test results. It is shown that the formulation of the FRP/concrete interfacial behaviour is essential to analyses utilizing finite element models. The implementation of interface elements produces accurate predictions of the response of shear-strengthened beams. Furthermore, the numerical analysis provides useful information on the slips and propagation of debonding along the FRP/concrete interfaces. Predicted strain profiles along the FRP sheet depth are also presented. Regression equations based on the statistical approach of the response surface methodology (RSM) are developed. New design equations to describe the FRP axial effective strain at the state of debonding are proposed for both side-bonded and U-wrap strengthening schemes. The proposed design equations can be used to provide simple design guidelines to predict the FRP shear contribution. Some of the results of this thesis research can be found in Godat et al. [2007a,b].
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Tann, David Bohua. "Retrofitting of mechanically degraded concrete structures using fibre reinforced polymer composites." Thesis, University of South Wales, 2001. https://pure.southwales.ac.uk/en/studentthesis/retrofitting-of-mechanically-degraded-concrete-structures-using-fibre-reinforced-polymer-composites(efce1110-34e1-457d-8ec5-3ef5da026018).html.
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This research involves the study of the short term loaded behaviour of mechanically degraded reinforced concrete (RC) flexural elements, which are strengthened with fibre reinforced polymer (FRP) composites. The two main objectives have been: (a) to conduct a series of realistic tests, the results of which would be used to establish the design criteria, and (b) to carry out analytical modelling and hence develop a set of suitable design equations. It is expected that this work will contribute towards the establishment of definitive design guidelines for the strengthening of reinforced concrete structures using advanced fibre composites. The experimental study concentrated on the laboratory testing of 30 simply supported, and 4 two-span continuous full size RC beams, which were strengthened by either FRP plates or fabric sheets. The failure modes of these beams, at ultimate limit state, were examined and the influencing factors were identified. A premature and extremely brittle collapse mechanism was found to be the predominant type of failure for beams strengthened with a large area of FRP composites. A modified semi-empirical approach was presented for predicting the failure load of such over strengthened beams. Despite the lack of ductility in fibre composites, it was found that the FRP strengthened members would exhibit acceptable ductile characteristics, if they were designed to be under strengthened. A new design-based methodology for quantifying the deformability of FRP strengthened elements was proposed, and its difference to the conventional concept of ductility was discussed. The available techniques for ductility evaluation of FRP strengthened concrete members were reviewed and a suitable method was recommended for determining ductility level of FRP strengthened members. A non-linear material based analytical model was developed to simulate the flexural behaviour of the strengthened and control beams, the results were seen to match very well. The parametric study provided an insight into the effects of various factors including the mechanical properties and cross sectional area of FRP composites, on the failure modes and ductility characteristics of the strengthened beams. Based on the findings of the experimental and analytical studies, design equations in the BS 8110 format were developed, and design case studies have been carried out. It was concluded that fibre composites could effectively and safely strengthen mechanically degraded reinforced concrete structures if appropriately designed. The modes of failure and the degree of performance enhancement of FRP strengthened beams depend largely on the composite material properties as well as the original strength and stiffness of the RC structure. If the FRP strengthened elements were designed to be under-strengthened, then the premature and brittle failure mode could be prevented and ductile failure mode could be achieved. It was also found that existing steel reinforcement would always yield before the FRP composite reached the ultimate strength. Furthermore, a critical reinforcement ratio, above which FRP strengthening should not be carried out, was defined. It was concluded that FRP strengthening is most suitable for reinforced concrete floor slabs, bridge decks, flanged beams and other relatively lightly reinforced elements. The study also revealed that to avoid a brittle concrete failure, existing doubly reinforced members should not be strengthened by FRP composites.
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Zenia, Sofiane. "Modélisation numérique de l’usinage des matériaux composites à matrice polymère et fibres longues de carbone." Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0126/document.
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La mise en œuvre des matériaux composites, fait souvent appel à des procédés d’usinage conventionnel, comme l’opération de perçage utilisée lors de l’assemblage de structures par rivetage. Ces opérations peuvent générer dans la pièce usinée différents types d’endommagement: arrachement des fibres, rupture de la matrice, délaminage intralaminaire et interlaminaire, dégradation thermique de la matrice, ce qui peut provoquer une baisse des performances mécaniques de la structure. L’objectif de la thèse est de mettre en place un modèle numérique scientifiquement rigoureux pour analyser l’usinage des composites CFRP et prédire les mécanismes d’endommagement induits par l’outil coupant. Ce modèle basé sur une loi constitutive mésomécanique combine l’effet de la chute de rigidité dans le comportement du matériau, la plasticité, l’initiation et l’évolution de l’endommagement durant le processus d’usinage. Ensuite, deux modèles 2D et 3D adoptant un schéma explicite ont été implémentés via la sub-routine VUMAT dans Abaqus. Le délaminage interplis a été pris en considération à l’aide des éléments cohésifs disponibles dans le code ABAQUS/Explicit. Ce travail a permis de reproduire de manière réaliste les opérations de coupe orthogonale et de perçage des composites CFRP en termes de processus de formation du copeau, la prédiction des forces de coupe et celle de l’endommagement induit. Ces études ont montré que l’orientation des fibres et la profondeur de coupe sont les paramètres les plus influents en coupe orthogonale tandis que pour le perçage se sont les vitesses d’avance et la géométrie des outilsThe machining of composite materials is often necessary for material removal operations by cutting tools such as drilling. These operations can generate a lot of damage in the machined workpiece (fiber fracture, matrix craking, intralaminar and interlaminar delamination and thermal degradation of the matrix), which can cause a decrease of mechanical performance of the structure. The PhD thesis objective is to set up a reliable accurate model to analyze the machining of CFRP composites and to predict the different damage modes induced by the cutting tool. This model is based on a mesomechanical constitutive law combining the stiffness degradation concept into the material behavior, the plasticity, the initiation and the evolution of the damage during the machining process. Two 2D and 3D models adopting an explicit scheme were implemented in Abaqus/Explicit analysis code through the user subroutine VUMAT. Furthermore, interlaminar delamination is taken into account using the cohesive elements available in the ABAQUS / Explicit code. This work allowed to realistic numerical simulation of orthogonal cutting and drilling operations of CFRP composites in terms of chip formation process, cutting forces prediction and induced damage. These studies have shown that the fiber orientation and the depth of cut were the most influential parameters in orthogonal cutting while for the drilling process, the feed rate and the tool geometry are the most important parameters
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Rosala, George Florin. "The process mechanics of polymer pipes welding by electro-fusion : a theoretical and experimental analysis of the electro-fusion welding process applied to polymer pipes. Process modelling using finite element and finite difference methods." Thesis, University of Bradford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.574642.
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This thesis presents a theoretical and experimental investigation into the modelling of the electro-fusion process, applied to welding polymer pipes. The theoretical background of the transient heat transfer between the fitting and pipe, including variable interface thermal resistance and involving consecutive changes of phase (melting and re-solidification) and the problem of the thermo-mechanical induced stresses in the joint, are fully discussed. Three 2D axisymmetric models of the EFW process, with different degrees of complexity, have been developed, refined and validated by comparison with experimental data: a finite element coupled model, with both temperature and displacement degrees of freedom, and two sequential heat transfer models, finite element and finite difference based. The effect of the melt movement into the fitting-pipe initial clearance is discussed and has been modelled by a 'virtual material movement' method. For the sequential models a 'gap evolution model' has been developed to describe the closure of the initial fitting-pipe gap through the process. Results from the simulations of the electro-fusion welding process performed using all three models, which give an exceptionally good insight into the temperature, displacement and stress fields within the joint, are fully discussed and validated through comparison with experimental data.
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Guan, Juan. "Investigations on natural silks using dynamic mechanical thermal analysis (DMTA)." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:c16d816c-84e3-4186-8d6d-45071b9a7067.
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This thesis examines the dynamic mechanical properties of natural silk fibres, mainly from silkworm species Bombyx mori (B. mori) and spider species Nephila edulis, using dynamic mechanical thermal analysis, DMTA. The aim is not only to provide novel data on mechanical properties of silk, but also to relate these properties to the structure and morphology of silk. A systematic approach is adopted to evaluate the effect of the three principal factors of stress, temperature and hydration on the properties and structure of silk. The methods developed in this work are then used to examine commercially important aspects of the ‘quality’ of silk. I show that the dynamic storage modulus of silks increases with loading stress in the deformation through yield to failure, whereas the conventional engineering tensile modulus decreases significantly post-yield. Analyses of the effects of temperature and thermal history show a number of important effects: (1) the loss peak at -60 °C is found to be associated the protein-water glass transition; (2) the increase in the dynamic storage modulus of native silks between temperature +25 and 100 °C is due simply to water loss; (3) a number of discrete loss peaks from +150 to +220°C are observed and attributed to the glass transition of different states of disordered structure with different intermolecular hydrogen bonding. Excess environmental humidity results in a lower effective glass transition temperature (Tg) for disordered silk fractions. Also, humidity-dynamic mechanical analysis on Nephila edulis spider dragline silks has shown that the glass transition induces a partial supercontraction, called Tg contraction. This new finding leads to the conclusion of two independent mechanisms for supercontraction in spider dragline silks. Study of three commercial B. mori cocoon silk grades and a variety of processed silks or artificial silks shows that lower grade and poorly processed silks display lower Tg values, and often have a greater loss tangent at Tg due to increased disorder. This suggests that processing contributes significantly to the differences in the structural order among natural or unnatural silks. More importantly, dynamic mechanical thermal analysis is proposed to be a potential tool for quality evaluation and control in silk production and processing. In summary, I demonstrate that DMTA is a valuable analytical tool for understanding the structure and properties of silk, and use a systematic approach to understand quantitatively the important mechanical properties of silk in terms of a generic structural framework in silk proteins.
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McGee, Seán. "Thermal energy management and chemical reaction investigation of micro-proton exchange membrane fuel cell and fuel cell system using finite element modelling." Thesis, KTH, Kraft- och värmeteknologi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-173001.
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Fuel cell systems are becoming more commonplace as a power generation method and are being researched, developed, and explored for commercial use, including portable fuel cells that appear in laptops, phones, and of course, chargers. This thesis examines a model constructed on inspiration from the myFC PowerTrekk, a portable fuel cell charger, using COMSOL Multiphysics, a finite element analysis software. As an educational tool and in the form of zero-dimensional, two-dimensional, and three-dimensional models, an investigation was completed into the geometric construction, air conditions and compositions, and product materials with a best case scenario completed that summarizes the results identified. On the basis of the results of this research, it can be concluded that polyoximetylen and high-density polyethylene were considered as possible materials for the majority of the product, though a more thorough investigation is needed. Air flow of above 10 m/s, air water vapour mass fraction below 50% and initial temperature between 308K and 298K was considered in this best scenario. Suggestions on future expansions to this project are also given in the conclusion.
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Kgorane, Nomathemba. "Adsorption modelling of desulphurisation of light diesel fuel using Chloramine T and Polymer Supported Imidation Agent." Thesis, 2017. https://hdl.handle.net/10539/24856.
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A research report submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Science in Engineering (Metallurgy and Materials Engineering) October 2017In petroleum industry, sulphur compounds are undesirable due to potential corrosions and environmental challenges associated with these compounds. Sulphur occurs in varies forms in crude oil and petroleum products such as, marcaptans, disulphide, sulphides, disulphide H2S and thiophenes. Commercial scale refineries utilises hydrodesulphurisation to reduce the sulphur content in fuels, though this technology is associated with high operating and capital cost. Extractive, adsorptive, oxidative, membrane separation and bio desulphurisation are some of the alternative technology being investigated which have proven not to be as efficient and/or cost effective as compared to hydrodesulphurisation. Adsorption desulphurisation has been effective in separation processes where the sorbate concentrations are low and this technology was used to evaluate the performance of the polymer supported imidation agent (Sodium N-chloro-polystyrene sulphonamide) as an adsorbent in diesel fuel desulphurisation. A mathematical model simulating adsorption on a fixed was developed. This model incorporates internal mass transfer assuming laminar flow, constant interstitial velocity and an isothermal system. To represent liquid solid equilibrium the Langmuir isotherm was used. The model contains partial differentiate equation that were linearised by using the Euler’s forward implicit method, this enabled simulating the model using Microsoft Excel Visual Basic. The obtained simulation results were compared against experimental data. The impact of varying parameters such as initial sulphur concentration, adsorbent bed porosity and external bed surface area per particle volume was studied in detail. Existing isotherms and kinetics were discussed by using experimental data from Fadhel’s study. It was found that the adsorbate residence time is reduced by smaller adsorbent bed porosity resulting in increased adsorption rate. By decreasing the adsorbent particle diameter and an increase in initial sulphur concentration, the breakthrough time is decreased. The experiment data agreed with the simulation results and this validate that the proposed model is applicable to study the performance of fixed bed adsorption processes under isothermal conditions, no axial mixing and constant interstitial velocities. The results from the analysed Fadhel’s data showed that the modelled light oil can be desulphurise to the Euro 5 level requirements, Sulphur <500ppm, by both Chloramine T and Synthesis PI, a complete sulphur removal was achieved using both adsorbents. The desulphurisation rate proved to be faster with Chloramine T as an adsorbent as compared to Synthesis PI. Modelled light oil adsorption obeyed the pseudo-first-order kinetics and the overall adsorption rate was controlled by the chemisorption process. The diesel fuels study by Fadhel could not be desulphurised to the Euro 5 level. The diesel fuel 1 sulphur concentration was reduced from 12 354 to 11 200ppm and diesel fuel 2 from 1 900 to 800ppm. It was observed that the rate of desulphurisation proved to be faster with diesel fuel 1 as compared to that of diesel fuel 2. The Freundlich isotherm was found to be a best fit in the adsorption of diesel fuel 1, the attained R square values was 0.881 and 0.435 for Freundlich and Langmuir, respectively. Also the obtained Langmuir separation factor, RL , of 1 confirmed the that the Langmuir adsorption was unfavourable. This implies that the adsorption rate was controlled by a physisorption process. The diesel fuel 2 desulphurisation process did not fit the studied adsorption isotherms, the attained R square values was 0.433 and 0.218 for Freundlich and Langmuir, respectively. The Langmuir separation factor confirmed in-favourability at 1 and the Freundlich adsorption strength was 6.052, which is very low as compared to that pf diesel fuel 1 at 272.41. Diesel fuel 1 adsorption reaction obeyed the pseudo-second and pseudo-first order kinetics when reacted with Chloramine T and Synthesis PI, respectively. The obtained R squared values were 0.694 and 0.999 for pseudo-second and pseudo-first order, respectively. Diesel fuel 2 obeyed the third order kinetics with both Chloramine T and Synthesis PI, with R squared values calculated at 0.889 and 0.774 for Chloramine T and Synthesis PI reaction, respectively.
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Silva, Cátia Samanta Ribeiro. "Polymeric microsensors using microtechnologies." Doctoral thesis, 2016. http://hdl.handle.net/1822/42537.
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Tese de Doutoramento - Programa Doutoral em Ciência e Engenharia de Polímeros e CompósitosThe work present here aims to combine advanced and specialized polymeric materials and microtechnologies with silicon based microtechnologies to develop an innovative concept for a thermal convective accelerometer with improved performance while also overcoming existing limitations. Thermal convective accelerometers have a transduction mechanism based in heat transfer by convection over a working fluid. The thermal accelerometer is a relatively recent technology and although research focused in improving many properties, parameters and processing techniques, thermal accelerometers still present some drawbacks regarding the power consumption caused by thermal losses through the fabrication material (typically silicon based) and limited third sensing dimension (planar silicon based microtechnologies). New developments towards the optimization of the existing thermal accelerometers may limit the power consumption and allow an easy integration of a Z-axis sensitive dimension. The methodology from the development of a concept to the actual fabrication and characterization requires a series of steps that need to be followed in a sequential way, namely: design and simulation analysis of the device concept (considering the electrical, thermal and fluidic domains), based on CAD and FEM techniques (using a FSI approach); development (project and simulation analysis) of tools based on CAD and CFD techniques; definition and optimization of a fabrication methodology (combination of polymeric and silicon based microtechnologies); and a full characterization of the fabricated device (sensitivity, bandwidth, dynamic range, and power). A three-axes thermal convective accelerometer was fully manufactured containing two main components: a polymeric based external structure fabricated my means of microinjection moulding technology that generates an isolated chamber from outside influences while supporting the second component, a polymeric flexible membrane that sustains and protects the metallic heating and sensing elements fabricated by microtechnologies. The proposed solution for the fabrication of a three-dimensional polymer based thermal accelerometer based in convection is innovative and the main contribution will be the use of polymeric materials not commonly used in microsystem technology and in electronic and instrumentation systems that are suitable to solve the main problems related to the current stateof- art of thermal accelerometers. Fabricated accelerometers were fully tested and characterized presenting a XY-axes sensitivity around 8 mV/g, a Z-axis sensitivity of 2.2 mV/g, and a 4 Hz bandwidth for a power of 45 mW. Thermal tests performed show that the heater can sustain up to 280 ºC without overheating the remaining structures and damaging the device. The developed technology has huge potential for functional highly complex threedimensional geometries at the micro-scale.
O trabalho aqui apresentado tem como intuito combinar materiais e microtecnologias poliméricas avançadas e especializadas com microtecnologias à base de silício para o desenvolvimento de um conceito inovador para um acelerómetro térmico convectivo com um desempenho melhorado superando também as limitações existentes. Os acelerómetros térmicos convectivos tem um mecanismo de transdução baseado na transferência de calor por convecção através de um fluído funcional. O acelerómetro térmico é uma tecnologia relativamente recente e embora os estudos científicos se tenham focado na otimização de diversas propriedades, parâmetros e técnicas de processamento, os acelerómetros térmicos ainda apresentam algumas desvantagens relativas ao consumo energético provocado pelas perdas térmicas através do material de fabrico (normalmente à base de silício) e também uma terceira dimensão sensível limitada (microtecnologias planares à base de silício). Novos desenvolvimentos no sentido da otimização dos existentes acelerómetros térmicos podem limitar o consumo energético e permitir uma integração mais fácil da dimensão sensível do eixo dos ZZ. A metodologia desde o desenvolvimento do conceito até à atual fabricação e caracterização requere uma série de etapas que necessitam de ser seguidas de uma forma sequencial, nomeadamente: projeto e análise por simulação do conceito do dispositivo (considerando os domínios elétrico, térmico, e fluídico), com base em técnicas CAD e FEM (através de uma abordagem FSI); desenvolvimento (projeto e análise por simulação) de ferramentas com base em técnicas CAD e CFD; definição e otimização de uma metodologia de fabrico (combinação de microtecnologias de polímeros com microtecnologias à base de silício); e uma caracterização completa do dispositivo fabricado (sensibilidade, largura de banda; gama dinâmica, e energia). Um acelerómetro térmico convectivo com três eixos foi inteiramente fabricado contendo dois componentes principais: uma estrutura externa à base de polímeros fabricada através da tecnologia de moldação por microinjeção gerando uma câmara isolada de influências externas que suporta o segundo componente, uma membrana polimérica flexível que sustem e protege os elementos metálicos de aquecimento e sensoriais fabricados por microtecnologias. A solução proposta para o fabrico de um acelerómetro térmico polimérico tri-dimensional baseado em convecção é inovativa e a principal contribuição consiste no uso de materiais poliméricos não comumente utilizados na tecnologia de microsistemas e na electrónica e instrumentação de sistemas que são adequados para solucionar os principais problemas relacionados com o atual estado da arte dos acelerómetros térmicos. Os acelerómetros fabricados foram testados e caracterizados apresentando uma sensibilidade de cerca de 8 mV/g para os eixos XY e 2.2 mV/g para o eixo ZZ, e uma largura de banda de 4 Hz para uma energia de 45 mW. Foram realizados testes térmicos demonstrando que a resistência de aquecimento consegue suportar até 280 ºC sem sobreaquecimento das restantes estruturas e sem danificar o dispositivo. A tecnologia desenvolvida apresenta um grande potencial para geometias tri-dimensionais altamente complexas e funcionais à escala micro.
Portuguese Fundação para a Ciência e a Tecnologia (FCT), for the financial support under the PhD scholarship SFRH/BD/78372/2011). The work was supported by FEDER through COMPETE and national funds through FCT in the framework of the project PTDC/EEA-ELC/099834/2008. The author would like to acknowledge the doctoral program in Science and Engineering of Polymers and Composites for supporting this work.
Books on the topic "Polymer modelling usingy"
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Allen, Michael P., and Dominic J. Tildesley. Advanced Monte Carlo methods. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198803195.003.0009.
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This chapter describes the ways in which the Monte Carlo importance sampling method may be adapted to improve the calculation of ensemble averages, particularly those associated with free energy differences. These approaches include umbrella sampling, non-Boltzmann sampling, the Wang–Landau method, and nested sampling. In addition, a range of special techniques have been developed to accelerate the simulation of flexible molecules, such as polymers. These approaches are illustrated with scientific examples and program code. The chapter also explains the analysis of such simulations using techniques such as weighted histograms, and acceptance ratio calculations. Practical advice on selection of methods, parameters, and the direction in which to make comparisons, are given. Monte Carlo methods for modelling phase equilibria and chemical reactions at equilibrium are described.
Book chapters on the topic "Polymer modelling usingy"
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Berge, A., T. Ellingsen, A. T. Skjeltorp, and J. Ugelstad. "Modelling of Physical Processes Using Monosized Polymer Particles." In Scientific Methods for the Study of Polymer Colloids and Their Applications, 435–52. Dordrecht: Springer Netherlands, 1990. http://dx.doi.org/10.1007/978-94-009-1950-1_20.
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Ivankovic, A., and J. G. Williams. "Modelling Dynamic Fracture in Polymers Using a Local Modulus Concept." In Dynamic Failure of Materials, 378–96. Dordrecht: Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-3652-5_27.
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Hood, Angus, Shaun Slater, Matthew Bouchet, Sheikh Zahidul Islam, and Mamdud Hossain. "Parametric Study of Polymer Electrolyte Membrane Fuel Cell Performance Using CFD Modelling." In Renewable Energy in the Service of Mankind Vol I, 159–71. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-17777-9_15.
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Burriss, Elise T., Gursel Alici, Geoffrey M. Spinks, and Scott McGovern. "Modelling and Performance Enhancement of a Linear Actuation Mechanism Using Conducting Polymers." In Informatics in Control Automation and Robotics, 63–78. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-19730-7_5.
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Kumar, Rajneesh, Prabhat Agnihotri, Rohit Kumar, Pradyumn Yadav, and Pawan Kumar Arora. "Review on Process Parameters of FDM and Their Impact on Flexure Strength of Additive Manufacturing Specimen." In Advances in Transdisciplinary Engineering. IOS Press, 2022. http://dx.doi.org/10.3233/atde220807.
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Lately, analysts and researchers are dealing with issues regarding natural unevenness and a worldwide temperature alteration inferable from various utilization of composite materials arranged by manufactured strands and petrochemical polymers. Subsequently, a rising consideration has been dedicated to the innovative work of polymer composites supported with the normal filaments. The normal strands are the most reasonable option of engineered filaments because of their biodegradability, eco-benevolence and mechanical properties. The normal strands are drawing in the specialists and researchers to take advantage of their properties by amalgamating them with the polymer. The properties of normal fiber built up polymer composites basically rely on different factors, for example, properties of filaments and lattices, fiber stacking rate, size and direction of strands, stacking groupings, level of interfacial holding, fiber surface medicines, hybridization and fuse of added substances and coupling specialists. Elastic and flexural tests are the main examinations to foresee the uses of the materials. A lot of exploration has been done of flexural properties of regular fiber supported polymer. In this paper, a survey on weakness and flexural properties of regular fiber supported polymer as far as impacts of fiber process parameter like Layer thickness, Infill density, Extrusion temperature, print speed using 3-D printer and process of fused deposition modelling (FDM). So, Analysis of data we have used Taguchi Analysis and compared with ANN (Artificial Neural Networks). Additionally, late utilizations of regular fiber supported polymer are likewise introduced in this review.
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Chan, P. H., K. Y. Tshai, M. Johnson, and S. Li. "Finite element analysis (FEA) modelling of fiber-reinforced polymer (FRP) repair in offshore risers." In Rehabilitation of Pipelines Using Fiber-reinforced Polymer (FRP) Composites, 177–210. Elsevier, 2015. http://dx.doi.org/10.1016/b978-0-85709-684-5.00009-6.
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Hulatt, J., L. C. Hollaway, and A. M. Thorne. "MODELLING A COMPOSITE/CONCRETE T-BEAM USING A FINITE ELEMENT TECHNIQUE." In Advanced Polymer Composites for Structural Applications in Construction, 361–68. Elsevier, 2004. http://dx.doi.org/10.1533/9781845690649.4.361.
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Haghani, R. "Finite element modelling of adhesive bonds joining fibre-reinforced polymer (FRP) composites to steel." In Rehabilitation of Metallic Civil Infrastructure Using Fiber Reinforced Polymer (FRP) Composites, 60–95. Elsevier, 2014. http://dx.doi.org/10.1533/9780857096654.1.60.
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Carreras, Laura, Gerard Guillamet, Adrià Quintanas-Corominas, Jordi Renart, and Albert Turon. "Mesoscale modelling of delamination using the cohesive zone model approach." In Multi-Scale Continuum Mechanics Modelling of Fibre-Reinforced Polymer Composites, 555–77. Elsevier, 2021. http://dx.doi.org/10.1016/b978-0-12-818984-9.00018-4.
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Reese, Stefanie, and Böl Markus. "Computational testing and modelling of polymers and soft tissue using chain statistics." In Constitutive Models for Rubber IV, 155–64. Routledge, 2017. http://dx.doi.org/10.1201/9781315140216-26.
Full textConference papers on the topic "Polymer modelling usingy"
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John, Anthony Okon, Ogbonna Friday Joel, and Franklin Chukwuma. "Modelling Degradation Time of Hydroxyethyl Cellulose-Based Polymeric Fluids." In SPE Nigeria Annual International Conference and Exhibition. SPE, 2022. http://dx.doi.org/10.2118/212022-ms.
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Abstract Sand production from hydrocarbon wells is known not to have any economic value. Hydroxyethyl cellulose is one of the polymers of choice used to formulate gravel carrier fluids used to transport proppants to the desired intervals in hydrocarbon wells, drilled in unconsolidated formations, to stop or minimize sand production. Viscous polymeric fluids must be degraded to ensure good wellbore cleanout and good hydrocarbon production. Polymer Degradation is a function of several variables such as temperature, pH, salinity, type and concentration of gel breakers and polymers. The success of gravel pack operations in the field depends greatly on the fluid design, which must first be qualified in the laboratory. It is often difficult to predict the degradation time of polymer fluids used in gravel pack operations because it’s a function of many variables. Therefore, in this study, a more detailed study of the effect of temperature, sodium persulfate breaker concentration and hydroxyethyl cellulose polymer concentration were performed. A model equation, capable of predicting the break time of hydroxyethyl cellulose-based polymeric fluid mixed in 2% by weight of potassium chloride brine, at various temperatures for different concentrations of sodium persulfate breaker, was developed based on data from laboratory experiments with the aid of Mini tab 17 software using factorial regression analysis. From the analysis, temperature has the highest impact on the degradation rate of hydroxyethyl cellulose with an effect estimate of -281.7, while breaker concentration and polymer concentration have an effect estimate of -113.4 and 128.8 respectively. From the analysis of variance, the coefficient of determination, R Squared, was 0.8792. The process of degradation of hydroxyethyl cellulose-based fluid similar composition can be more easily and faster optimized using this model.
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Daan, Boris, Jelle Rommers, and Just L. Herder. "Modelling the Axis Drift of Short Wire Flexures and Increasing Their Support Stiffness Using Polymers." In ASME 2021 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/detc2021-68255.
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Abstract For steel flexures, complex geometries are required to reach high support stiffness and limit axis drift over large ranges of motion. These complex flexures are expensive and difficult to manufacture. This paper presents a method of designing short, polymer wire flexures with high support stiffness and modelling their axis drift using a novel method, the arc method. The arc method is validated against finite element methods (FEM) and physical tests, showing at least a factor 10 lower error than existing pseudo-rigid-body models (PRBM) at 70° deflection, while maintaining a simple modelling approach. The use of polymers increases support stiffness of wire flexures by a factor 7800 with respect to steel at 70° deflection, even though the material stiffness is substantially lower. This is due to the large allowed strain of polymers increasing the possible diameter by a factor 110.
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Ravndal, Kristin T., and Roald Kommedal. "Modelling particle degradation and intermediate dynamics in a dispersed activated sludge microcosm." In 63rd International Conference of Scandinavian Simulation Society, SIMS 2022, Trondheim, Norway, September 20-21, 2022. Linköping University Electronic Press, 2022. http://dx.doi.org/10.3384/ecp192002.
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Municipal wastewater consists of a large fraction of particulate organic matter. During biological wastewater treatment these particles undergo extracellular depolymerisation before products are taken up by bacteria (MW < 0.6 kDa). Particle degradation and intermediate formation dynamics is important in process analysis of wastewater treatment as the transport regime differ. This work aims to develop a model for particle degradation that includes intermediate dynamics as observed in experimental work. A model for particle degradation including intermediate dynamics, bacterial growth and endogenous respiration is proposed. Particle hydrolysis was modelled using the particle breakup model. Depolymerisation products were separated into five different size groups: colloids; high, medium and low molecular weight (HMW, MMW and LMW) polymers; and one fraction for oligomers and monomers (SB). Depolymerisation of colloids, HMW and MMW polymers was modelled using first order kinetics. LMW polymer degradation was modelled using Michaelis-Menten kinetics, while growth was based on traditional Monod kinetics and endogenous respiration followed ASM3. The proposed model was implemented in AQUASIM for a batch reactor system, and parameter estimation by LSE fitting to experimental data on particulate starch degradation over 117 days in a dispersed biomass microcosm was performed. Validation of the model against experimental data gave a very good fit to the PBM. The intermediate dynamics seen in the experimental data was also qualitatively demonstrated by the model, with accumulation of HMW, MMW and LMW polymers in the bulk liquid. However, the accumulation of monomers and oligomers in the bulk liquid could not be reproduced in the suspended growth model proposed. Hence, a structured biomass model (biofilm) is suggested for future work.
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Bernard, C. A., K. Ogawa, J. Y. Cavaillé, O. Lame, K. Ravi, and T. Deplancke. "On the Premise of Polymer Coating Modelling for Cold-Spray Process." In ITSC2018, edited by F. Azarmi, K. Balani, H. Li, T. Eden, K. Shinoda, T. Hussain, F. L. Toma, Y. C. Lau, and J. Veilleux. ASM International, 2018. http://dx.doi.org/10.31399/asm.cp.itsc2018p0366.
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Abstract Cold-spray process (CS) showed suitable properties to weld together compatible and incompatible materials. Since it has been intensively studied as additive technique using metallic powders on metallic surfaces, and only recently with polymeric powders, we compare, in a very preliminary attempt, simulated data of the impact of an aluminum particle onto aluminum substrate, with the case of an ultra-high molecular weight polyethylene (UHMWPE) particle on the same substrate. It is noteworthy that such polymer cannot be processed by classical means (extrusion, injection molding, etc.), and CS appears to be very promising as alternative technique to powder sintering (applicability on large surface area, surface curvature).
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Benseddiq, Noureddine, Moussa Nai¨t-Abdelaziz, and Nai¨ma Belayachi. "Numerical Modelling of Cavitation in Polymer-Rubber Blends." In ASME 2008 Pressure Vessels and Piping Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/pvp2008-61258.
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In the present study we have investigated the mechanical behaviour of multi-phase solid materials by using the micro-macro computational approach. Spherical rubber particles embedded in amorphous glassy polymer matrix are taken into account as the heterogeneous composite system. In order to predict the micromechanical deformation behaviour of the composite, we propose a combination of an appropriate elastic-viscoplastic constitutive equation describing the nonlinear behaviour of the polymeric matrix with a hyperelastic model for the rubbery phase. The dependence of the macroscopic stress-strain behaviour of matrix deformation, on cavitation of rubber particles is discussed. In order to describe the cavitation of the rubber particles, a criterion of void nucleation is implemented in the F. E. code. A comparison of the numerically predicted response with experimental result indicates that the numerical homogenisation analysis gives quite satisfactory prediction results.
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Ionita, Mariana, Davide Silvestri, Alfonso Gautieri, Emiliano Votta, Gianluca Ciardelli, and Alberto Redaelli. "Molecular Modelling of Small Molecule Diffusion in Biopolymer Blends Membranes for Biomedical Applications." In ASME 8th Biennial Conference on Engineering Systems Design and Analysis. ASMEDC, 2006. http://dx.doi.org/10.1115/esda2006-95671.
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In order to improve the biological performance of synthetic polymers and to enhance the mechanical characteristics by tailoring the permeability properties of biopolymers, a new class of specifically designed materials (bioartificial polymeric materials), consisting of blends of synthetic polymers and biopolymers, has been recently introduced. In this work we present a computational method based on molecular mechanics (MM) and dynamics (MD) techniques, to investigate their permeability to small molecules. The permeability properties was assessed of poly(vinyl alcohol)-(PVA)- dextran-(Dex) and poly(acrylic acid)-(PAA)-Dex membranes with different blend composition. Amorphous bulk models of PVA–Dex and PAA–Dex mixtures with 80:20, 60:40, 40:60 (w/w) ratios were generated. Two steps have been performed iteratively, the former using a MM simulation for equilibration and the latter using MD simulations for model refinement. Virtual uniaxial traction tests were performed, adopting the Second Derivative (SD) procedure, in order to assess the mechanical behavior of the bulk models. The diffusion coefficients for H2O were determined via NVT molecular dynamics simulations. Using the data of the motion of water inside the bulk models, the diffusivity constant was calculated applying the Einstein equation. Correlation of diffusion coefficients with free volume, was found. The results of the simulations agree with theoretical considerations: as the content of dextran increases from 80:20 to 40:60 a 86 % decrease of the diffusion constant is obtained and the values (range 0.14–56.5 10−6 cm2s−1) have the order of magnitude expected, and similar on the diffusion of small molecules in amorphous polymeric membranes.
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Hawari, Huzein Fahmi, Nurul Maisyarah Samsudin, Mohd Noor Ahmad, Ali Yeon Md Shakaff, Supri A. Ghani, Yufridin Wahab, and Uda Hashim. "Recognition of Limonene Volatile Using Interdigitated Electrode Molecular Imprinted Polymer Sensor." In 2012 3rd International Conference on Intelligent Systems, Modelling and Simulation (ISMS). IEEE, 2012. http://dx.doi.org/10.1109/isms.2012.103.
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Boutaous, M., E. Pe´rot, A. Maazouz, P. Bourgin, and P. Chantrenne. "Heat Transfer and Air Diffusion Phenomena in a Bed of Polymer Powder Using Apparent Heat Capacity Method: Application to the Rotational Molding Process." In ASME/JSME 2007 5th Joint Fluids Engineering Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/fedsm2007-37181.
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The process of rotational moulding consists in manufacturing plastic parts by heating a polymer powder in a biaxial rotating mould. In order to optimise the production cycle of this process, a complete simulation model has to be used. This model should describe the phenomena of heat and mass transfer in a moving granular media with phase change, coalescence, sintering, air evacuation and crystallization during the cooling stage. This paper focus on the study of heat and mass transfer in a quiescent polymer powder during the heating stage. An experimental device has been built. It consists in an open plane static mold on which an initial thickness, e, of a polymer powder is deposited. This powder is then heated until it melts. An inverse heat conduction method is used to determine the heat flux and temperature at the interface between the mold and the powder. This interfacial heat flux is taken as a boundary condition in a numerical heat transfer model witch takes into account the heat transfer in granular media with phase change, coalescence, sintering, air bubbles evacuation and rheological behaviour of the polymer. For the numerical simulation of the heat transfer, the apparent specific heat method is used. This approach allows to solve the same energy equation for all the material phases, so one do not have to calculate the melting front evolution. This fine modelling, close to the real physical phenomena makes it possible to estimate the temperature profile and the evolution of the polymer powder characteristics (phase change, air diffusion, viscosity, evolution of the thermophysical properties of the equivalent homogeneous medium, thickness reduction, air volume fraction...). Several results are then presented, and the influence of different parameters, like the thermal contact resistance, the process initial conditions and the polymer’s rheological characteristics are studied and commented. Indeed the predictions of the temperature rises in the polymer bed, agree well with the experimental measurements.
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Fechter, Reinhard, Ines Kühnert, Carl Sandrock, and Johan Labuschagné. "Modelling and optimization of the mechanical and other material properties of a polymer nanocomposite using statistical design of experiments." In PROCEEDINGS OF THE EUROPE/AFRICA CONFERENCE DRESDEN 2017 – POLYMER PROCESSING SOCIETY PPS. Author(s), 2019. http://dx.doi.org/10.1063/1.5084832.
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Rosenblatt, F., J. F. Morrison, and L. Iannucci. "Modelling electroactive polymer (EAP) actuators: electro-mechanical coupling using finite element software." In The 15th International Symposium on: Smart Structures and Materials & Nondestructive Evaluation and Health Monitoring, edited by Yoseph Bar-Cohen. SPIE, 2008. http://dx.doi.org/10.1117/12.776086.
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