Effect of structural parameters and materials choice on the mechanical characteristics of expansion tubes

Recently, triaxial braids made from ultra-high molecular weight polyethylene (UHMWPE) have been recognized as one of the most popular composite reinforcements in the aerospace and defense fields. To further explore the mechanical characteristics of this material, a detailed experimental study on tensile behavior is reported in this paper. The triaxial braids show a “double-peak” phenomenon in tensile strength and deformation, caused by axial yarns and the in-plane shearing of bias yarns. The evolution of the braiding angle, measured during these tensile tests, is discussed according to the braiding parameters (initial braiding angle, number of axial yarns). Using the high conductivity properties of the UHMWPE material, the temperature caused by inter-yarn friction during tensile tests is also studied. This temperature is related to the evolution of the braiding angle. The temperature increases with the increasing number of axial yarns and decreases with increasing braiding angle. This study provides an experimental database on the influence of braiding parameters on the tensile behavior of triaxial braids.

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Electromagnetic and Mechanical Characteristics Analysis of a Flat-Type Vertical-Gap Passive Magnetic Levitation Vibration Isolator

Shock and Vibration ◽

10.1155/2016/5327207 ◽

2016 ◽

Vol 2016 ◽

pp. 1-12

Author(s):

Baoquan Kou ◽

Yiheng Zhou ◽

Xiaobao Yang ◽

Feng Xing ◽

He Zhang

Keyword(s):

Vibration Isolation ◽

Mechanical Characteristics ◽

Magnetic Levitation ◽

Structural Parameters ◽

Force Density ◽

Vibration Isolator ◽

Isolation System ◽

Flat Type ◽

Characteristics Analysis ◽

Vertical Gap

In this paper, we describe a flat-type vertical-gap passive magnetic levitation vibration isolator (FVPMLVI) for active vibration isolation system (AVIS). A dual-stator scheme and a special stator magnet array are adopted in the proposed FVPMLVI, which has the effect of decreasing its natural frequency, and this enhances the vibration isolation capability of the FVPMLVI. The structure, operating principle, analytical model, and electromagnetic and mechanical characteristics of the FVPMLVI are investigated. The relationship between the force characteristics (levitation force, horizontal force, force ripple, and force density) and major structural parameters (width and thickness of stator and mover magnets) is analyzed by finite element method. The experiment result is in good agreement with the theoretical analysis.

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The effect of composite structural parameters on tribo‐mechanical characteristics and thermal conductivity of self‐lubricant composites

Polymer Composites ◽

10.1002/pc.26366 ◽

2021 ◽

Author(s):

Fatemeh Shahramforouz ◽

Seyed Mahdi Hejazi ◽

Aboozar Taherizadeh

Keyword(s):

Thermal Conductivity ◽

Mechanical Characteristics ◽

Structural Parameters

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Simultaneous Modeling of Young’s Modulus, Yield Stress, and Rupture Strain of Gelatin/Cellulose Acetate Microfibrous/Nanofibrous Scaffolds Using RSM

Frontiers in Bioengineering and Biotechnology ◽

10.3389/fbioe.2021.718718 ◽

2021 ◽

Vol 9 ◽

Author(s):

Alireza Barazesh ◽

Mahdi Navidbakhsh ◽

Ali Abouei Mehrizi ◽

Mojtaba Koosha ◽

Sajad Razavi Bazaz ◽

...

Keyword(s):

Mechanical Properties ◽

Cellulose Acetate ◽

Yield Stress ◽

Young’S Modulus ◽

Mechanical Characteristics ◽

Rotation Speed ◽

Young's Modulus ◽

Structural Parameters ◽

Weight Ratio ◽

Wide Range

Electrospinning is a promising method to fabricate bioengineered scaffolds, thanks to utilizing various types of biopolymers, flexible structures, and also the diversity of output properties. Mechanical properties are one of the major components of scaffold design to fabricate an efficacious artificial substitute for the natural extracellular matrix. Additionally, fiber orientations, as one of the scaffold structural parameters, could play a crucial role in the application of fabricated fibrous scaffolds. In this study, gelatin was used as a highly biocompatible polymer in blend with cellulose acetate (CA), a polysaccharide, to enhance the achievable range of mechanical characteristics to fabricated fibrous electrospun scaffolds. By altering input variables, such as polymers concentration, weight ratio, and mandrel rotation speed, scaffolds with various mechanical and morphological properties could be achieved. As expected, the electrospun scaffold with a higher mandrel rotation speed shows higher fiber alignment. A wide range of mechanical properties were gained through different values of polymer ratio and total concentration. A general improvement in mechanical strength was observed by increasing the concentration and CA content in the solution, but contradictory effects, such as high viscosity in more concentrated solutions, influenced the mechanical characteristics as well. A response surface method was applied on experimental results in order to describe a continuous variation of Young’s modulus, yield stress, and strain at rupture. A full quadratic version of equations with the 95% confidence level was applied for the response modeling. This model would be an aid for engineers to adjust mandrel rotation speed, solution concentration, and gelatin/CA ratio to achieve desired mechanical and structural properties.

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Analytical modeling and simulation on lateral mechanical characteristics of high-speed train traction motor hanging leaf spring

International Journal of Modeling Simulation and Scientific Computing ◽

10.1142/s179396231950017x ◽

2019 ◽

Vol 10 (03) ◽

pp. 1950017

Author(s):

Yuewei Yu ◽

Leilei Zhao ◽

Changcheng Zhou

Keyword(s):

High Speed ◽

Mechanical Characteristics ◽

Structural Parameters ◽

Analytical Formula ◽

Analytical Calculation ◽

Lateral Force ◽

Leaf Spring ◽

Force Model ◽

Traction Motor ◽

Influence Degree

In this paper, using the theoretical analysis method, according to the actual structure of the hanging leaf spring of the traction motor mounted on the frame, the lateral force model of the hanging leaf spring of the traction motor was established. Then, through theoretical deduction, the deformation analytical calculation formula and the stress analytical calculation formula of the hanging leaf spring were established. The correctness of the leaf spring’s lateral force model was established and its deformation and stress analytical formulae were verified using ANSYS finite element analysis software. Based on this, according to the deformation analytical formula and the stress analytical formula of the leaf spring established, the influence of the main structural parameters on the mechanical characteristics of the leaf spring was discussed, and the reliability of the analytical analysis method of the lateral mechanical characteristics of the traction motor hanging leaf spring was verified by the loading–unloading test. The results show that the deformation and the load of the leaf spring change linearly. The changes of leaf spring’s stress at different positions can be considered as being composed of three sections: a linear change section in the root, a nonlinear change section in the middle, and a nonlinear change section in the end. In the structural parameters, the end thickness [Formula: see text] has the greatest influence on the stiffness and the stress of the leaf spring, and the maximum thickness of the leaf spring eye [Formula: see text] has the least influence on the stiffness and the stress of the leaf spring. The influence degree of other parameters on the stiffness of the leaf spring is [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text] in order, and the influence degree on the stress of the leaf spring is [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text] in order. In addition, when the root thickness [Formula: see text] is greater than a certain value, the maximum stress point of the leaf spring appears at the end position [Formula: see text]. This study can provide a useful reference for the intelligent forward design and the rapid analysis of the mechanical characteristics of high-speed train traction motor hanging leaf spring.

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Finite Element Analysis of Mechanical Characteristics of Dropped Eggs Based on Fluid-Solid Coupling Theory

Shock and Vibration ◽

10.1155/2017/4512497 ◽

2017 ◽

Vol 2017 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

Song Haiyan ◽

Wang Fang ◽

Zhang Jianguo ◽

Zhang Yinong ◽

Yang Shugang

Keyword(s):

Finite Element ◽

Finite Element Model ◽

Mechanical Characteristics ◽

Structural Parameters ◽

Element Model ◽

Coupling Theory ◽

Element Analysis ◽

Internal Fluid ◽

Drop Impacts ◽

Protective Packaging

It is important to study the properties and mechanics of egg drop impacts in order to reduce egg loss during processing and logistics and to provide a basis for the protective packaging of egg products. In this paper, we present the results of our study of the effects of the structural parameters on the mechanical properties of an egg using a finite element model of the egg. Based on Fluid-Solid coupling theory, a finite element model of an egg was constructed using ADINA, a finite element calculation and analysis software package. To simplify the model, the internal fluid of the egg was considered to be a homogeneous substance. The egg drop impact was simulated by the coupling solution, and the feasibility of the model was verified by comparison with the experimental results of a drop test. In summary, the modeling scheme was shown to be feasible and the simulation results provide a theoretical basis for the optimum design of egg packaging and egg processing equipment.

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Modeling of the process of forming loads on the supporting and running elements of self-propelled jib cranes

Bulletin of Kharkov National Automobile and Highway University ◽

10.30977/bul.2219-5548.2021.95.0.114 ◽

2021 ◽

pp. 114

Author(s):

Valery Krupko ◽

Svitlana Yermakova ◽

Alexsandr Schukin

Keyword(s):

Mechanical Characteristics ◽

Structural Parameters ◽

Operating Conditions ◽

Factors Influencing

Factors influencing the load of crane elements are considered. A technique has been developed that allows modeling the process of forming loads on the support and running elements of self-propelled jib cranes taking into account the mechanical characteristics of support platforms, structural parameters of cranes, their supporting and running elements under different operating conditions and load modes of cranes.

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Mechanical Characteristics Analysis of Type ∏ Terminal Restricted Configuration Transition Section for CRTSⅡ Slab Track

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.90-93.108 ◽

2011 ◽

Vol 90-93 ◽

pp. 108-112

Author(s):

Xiao Ping Gong ◽

Hong Xiao

Keyword(s):

Mechanical Characteristics ◽

Structural Parameters ◽

Friction Angle ◽

Longitudinal Force ◽

Longitudinal Displacement ◽

Analysis Model ◽

Element Analysis ◽

Transition Section ◽

Foundation Plate ◽

Configuration Transition

With full-bridge longitudinal-connected foundation plates,CRTSⅡslab track sets type ∏ terminal restricted configuration anchorage structure in the bedroad-bridge transition section,in order to transmit forces such as temperature force and braking force from foundation plate to subgrade. In connection with the deficiency of exsiting researches, through the established finite element analysis model on Type ∏ terminal restricted configuration transition section,its mechanical characteristics under the most unfavorable longitudinal load by changing the structural parameters of transition section are analyzed, focusing on the criterion that the range of maximum of longitudinal displacement is 3mm.Analysis results show that when the longitudinal force is being transmitted to the anchorage structure, the maximum stress and longitudinal displacement of main terminal restricted configuration are far less than the limit and this process has little influence on track geometrical regularity .The laying of sliding layer can ameliorate structural force and deformation. However, changing its friction coefficient has no effect. Moreover, as the soil is under elastic deformation stage, its elastic modulus presents significant effects on mechanical properties of transmit section while its internal friction angle and cohesion have no influence.

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Analytical model of liner with previous loads

Mehanization and electrification of agricultural ◽

10.37204/0131-2189-2019-9-12 ◽

2019 ◽

pp. 99-106

Author(s):

Dmytriv, V. ◽

Dmytriv, I. ◽

Krasnytsia, B.

Keyword(s):

Cylindrical Shell ◽

Analytical Model ◽

Modulus Of Elasticity ◽

Mechanical Characteristics ◽

Structural Parameters ◽

Vacuum Pressure ◽

Central Angle ◽

Radial Plane ◽

Working Length ◽

Preliminary Tension

Purpose. Development analytical model of the liner, taking into account its previous tension, structural and technological parameters and physical-mechanical characteristics of the rubber material, for modeling its deformations in the radial, longitudinal and circular planes. Methods. Analytical, mathematical modeling. Results. On the basis of the equilibrium equations for a cylindrical shell, taking into account the isotropy of the medium and the without momentary stress state, the spatial of forces and the preliminary tension of the liner, a system of analytic equations is developed that enables modelling of the deformations of the liner, which is the factor of its closure. The analytical dependences of the deformation of the liner in the longitudinal, circular and radial planes, depending on its structural parameters and physical and mechanical characteristics of the material, are developed. Parameters for deformation simulation are: R – radius of liner, Е – modulus of elasticity, h – thickness of liner, рн – vacuum pressure, l – the length of the active part of liner, ν – Poisson's coefficient for rubber, Fн force of tension of liner. Depending on the central angle in the radial plane of the section, the shape of the deformation of the liner is simulated along its entire working length. Conclusions. The obtained dependences allow simulating the deformation of the liner in the longitudinal, circular and radial planes, depending on its structural parameters and physical-mechanical characteristics of the material. The developed analytical dependences take into account the preliminary tension of the liner, the vacuum pressure and makes it possible to model, depending on the central angle in the radial plane of the cross-section of rubber. The use of developed analytical dependencies makes it possible to substantiate the basic parameters that influence the technological process of milk yield cows Keywords: liner, vacuum pressure, modulus of elasticity, radial deformation, coordinate system, tension of rubber, the cylindrical shell, the isotropic medium.

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