Papers by Keyword: Experiment

Abstract: The paper presents selected results of experimental and computational modelling of composite material samples of tires with cord ply (casing) and breaker textile reinforcement. The computational modelling included applications of finite element methods. The output is to determine and verify the influence of material parameters of textile reinforcement. The results were confirmed by the experiment and computational modelling verification. For elastomeric matrices hyperelastic behavioural patterns of this material were considered.

Abstract: Electric bicycles are one of the two-wheeled transportation that has been widely used. The structure of the bicycle is generally composed of several components, one of which is the frame. The frame serves to support the load on the bicycle. At present, many changes in design, geometry and bicycle-forming materials have been carried out. In general, bicycle frames are made of metal and alloy because they have good strength to support the load of the driver. Lately, the use of composites has begun to develop as a bicycle frame material, because the frame of the bicycle has become lighter but still has the strength to support the load. This paper presents a study of the structure of electric bicycles using composite material based on epoxy matrices with rami fiber reinforcement. This study used an experimental and simulation method by designing composite laminates with A(90o/90o/90o), B(90o/45o/90o), and C(45o/45o/45o) fiber webbing layout and then carried out free compressive strength (UCS), optical microscopy and simulation using ANSYS 19.0 software. The results obtained are composite laminate design with a woven fiber layout (45o/45o/45o) having the highest strength value with a compressive stress value σ=58.64 MPa in the axial compressive plane, and σ=1.539 MPa in the tangential compressive plane. Likewise, the simulation results also obtained the highest strength in the webbing design (45o/45o/45o) which is equal σ_s=58.72 MPa in the axial compressive plane and σ_s=1.531 MPa in the tangential compressive plane.

Abstract: The detailed study devoted to instrumental diagnostic methods of bone tissue research was performed by authors. The main idea which is the basis for this work is the analysis and study of X-ray methods for examining bone tissue, highlighting their advantages. As a result of the work, we analyzed published scientific data in Russian and foreign literary sources, which addresses many instrumental methods of bone tissue research. After experiments a detailed description of the most common research methods related to the study of bone tissue was given, its structure and other functions. Analysis of the modern scientific data has shown that there is a great need to know the instrumental methods for studying human organs and systems, and their more accurate possibilities for identifying pathological processes, which will permit the use of the research method that in any particular case will be the most informative, which would provide timely diagnosis and its accuracy.

Abstract: The detailed research and analysis of modern data on the problem of methods of histological and immunohistochemical researches of connective tissue, bone in particular, was conducted by us so as to evaluate the possibility of creating a single method of bone tissue immunohistochemical analysis.The description was given in detail to most widespread methods of preparation of connective, bone in particular, tissues for the research conduction during experiments connected with the study of bone tissue regeneration including implants with bioactive coverage. The present-day medical data reflects a variety of methods of immunohistochemistry, as well as the experience of their use in complex trauma surgery. However, there is no consensus about which method and material are most reliable when conducting this analysis.

Abstract: The results of the numerical solution of the problem about interaction between spherical stamp and weakly compressible elastic specimen are investigated. The nonlinear generalization of linear elastic Hencky model is used as a constitutive relation. The results of the indentation problem solution are in good agreement with experimental data. The tests were performed on the kinematical loading fixture. The influence of geometrical parameters of specimen during indentation test on stress strain state and macro response are investigated.

Abstract: In the article research results are presented, which aim to provide evaluation of thermal protection properties of volume textile materials. However, as a result of experts wearing it has been revealed that by their operational performance their characteristicsare quite high to such materials: Holofiber, Tinsulate, Arctic, etc. At the present time to research thermal protection properties of sewing materials methods are used that can be divided into 2 groups: Methods based on the principle of steady heat mode and Methods based on the principle of unsteady (regular) mode. New device has been developed which allows to simplify both the schematic diagram and the methodological approach to experimental evaluation of thermal protection properties of volume textile materials. The corresponding experimental research were held based on the developed bicalorimeter. Study results allowed to establish heat insulation material «ArcticP» possesses the highest thermal resistance.It is located with its metallized coating facing outside. High values of thermal protection properties of this material are explained by availability of metallized coating from outer side which ensures partial heat reflection.. The research was made in Don State Technical University within the framework of State Assignment of the Ministry of education and science of Russia under the project 11.9194.2017/БЧ.

Abstract: In the article research results are presented, which aim to provide treated textile electrostatic properties study. In the article research results are presented, which aim to provide find out abilities of an anti-electrostatic treatment and binding agents for it in treatment of special textile materials and their dependance from modes of operating textile washing. Results of determine a composition and abilities of a functional impregnation; develop a method to study values of electrostatic field for tribocharging conditions of textile materialsare; experimental studies of electrostatic values of materials with functional treatment depending on operating washing modes also presented here. Study results allowed to establish efficiency of the proposed combination of anti-electrostatic active composition based on 5 % solution of dialkyldimethylammonium chloride with a binding agent with the effect to preserve the treatment in the material structure and content of which is 4 % in application of textile fabric with widely used fiber content (cotton 53 %, polyester + oil and water-proofing finish). Acrylic dispersion is stable film-forming component suitable in preserving anti-electrostatic treatment on the surface of a textile material. The research was made in Don State Technical University within the framework of State Assignment of the Ministry of education and science of Russia under the project 11.9194.2017/BCh.

Abstract: . Electrochemical etching is widely used to process refractory metals such as tungsten and molybdenum. Flow field is one of the crucial factors that influence the surface quality in electrochemical etching. In this paper, the electrochemical etching flow field was analyzed via FLUENT, the characteristics of flow field in electrochemical etching are studied, furthermore, the effects of four different outlet forms of electrolyte on flow field uniformity, electrolyte velocity and pressure distribution are investigated. Under the same electrolyte flow rate, the flow field characteristics of different outlet forms are analyzed by velocity vector diagram, pressure distribution nephogram, velocity and pressure curve diagram. The simulation results indicate that stable electrolyte velocity and uniform pressure distribution of flow field are obtained when the outlet form of electrolyte adopts the optimized flat. Finally, the fixture for this outlet form is designed and fabricated, and experimental verification is carried out, which shown that the flow field is uniform and the crystal plane of the workpiece is well-distributed which according with the process requirements.

Abstract: Paper is devoted to the automation of processing the results of measurements of mechanical characteristics of plated specimens and the creation of a mathematical model of anisotropy material. Methods of conducting tensile and flexural tests are described. Developed in MATLAB tools for automation of processing results of experiments are proposed. Tools can be used for interpretation of the results of strength tests of isotropic and composite materials. The advantage of the developed tools is batch processing, which allows processing the results of a large series of experiments. The tools system was tested when creating a model of short-reinforced composite material. An example of the use of test results when constructing the Digimat material model and using this model to predict the stress-strain state of anisotropic structures is presented.

Abstract: The Brookfield_to_MATLAB and ViscosityApproximation codes for processing of experiments results for determination of viscosity on a rotational Brookfield DV3T viscometer is developed in the MATLAB. The codes allow to carry out automatic capture data, to calculate the shear rate for standard spindles RV-1 ... RV-7, to sort the measurement results on temperatures, to combine the experimental data and to determine the coefficients of the Andrade type power-law model. Paper describes experiment results on determination of viscosity of the epoxy binder reinforced by short carbon fibers. The coefficients of the viscosity model are determined by the linear regression coefficients. The obtained determination coefficient shows a good agreement of the model with the experimental data. The results are used for study various contents of a mass fraction of fibers: 0%, 5%, 10%, and 15%.