Numerical Modeling of Thermobonded Nonwovens

2004 ◽  
Vol os-13 (1) ◽  
pp. 1558925004os-13 ◽  
Author(s):  
Dieter H. Mueller ◽  
Markus Kochmann
Keyword(s):  
Experimental Data ◽  
Nonlinear Behavior ◽  
Fiber Material ◽  
Tensile Behavior ◽  
Fiber Bundles ◽  
The Finite Element Method ◽  
Technological Parameters ◽  
Numerical Effort ◽  
Production Techniques ◽  
Temperature And Pressure

In thermobonded nonwovens, the design of the bond point geometry is of major importance to the desired mechanical behavior. Despite the geometry's significance the selection is subject to a trial and error approach. This paper describes a numerical method for the prediction of the nonwovens tensile behavior depending on the bond point geometry and process parameters. The tensile behavior of thermobonded nonwovens is modeled in a numerical model using the Finite Element Method (FEM). The approach covers the influence of the shape and size of the bonded area as well as the properties of the non-woven. The influence of the technological parameters during the bonding process such as process temperature and pressure, are also covered. The solidified area within the bond point is represented using solid elements. The connection between the bonded areas is modeled using link elements, representing the connecting fibers. This approach covers the nonlinear behavior caused by the fiber material properties and geometry. Sets of fibers are combined into fiber bundles in order to reduce the numerical effort. The fiber orientation within the nonwoven is taken into account in order to represent the different fiber distributions caused by the nonwovens production techniques. The mechanical properties of fibers and fiber bundles are taken from experimental data and are mapped onto the model. The model is verified using experimental data from tensile testing.

scholarly journals Design, Simulation and Optimization of an Additive Laser-Based Manufacturing Process for Gearbox Housing with Reduced Weight Made from AlSi10Mg Alloy

Metals ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 67
Author(s):  
Liubov Magerramova ◽  
Vladimir Isakov ◽  
Liana Shcherbinina ◽  
Suren Gukasyan ◽  
Mikhail Petrov ◽  
...  
Keyword(s):  
Experimental Studies ◽  
Strength Properties ◽  
Body Parts ◽  
The Finite Element Method ◽  
Technological Parameters ◽  
Simulation And Optimization ◽  
Precision Casting ◽  
Production Techniques ◽  
Material Forming ◽  
Physical And Mechanical Characteristics

The gas turbine engine's (GTE) development aims for the increasing the efficiency, strength, reliability and safety of its components. To create competitive engines, housing parts and components with high functionality and reduced weight are needed. Especially difficult in the design and production are the gearboxes for aviation GTE. Traditional technologies based on precision casting or material forming operations have significant limitations due to the complexity of fulfilling multiple different requirements. Nowadays, one of the progressive production techniques is additive manufacturing. The article presents the results of computational and experimental studies that substantiate the applicability of laser additive technology to reduce the mass of body parts by up to 15% while ensuring their strength properties. The physical and mechanical characteristics of aluminum alloys acceptable for the manufacturing of housing parts were analyzed. The necessary characteristics of the powder alloy of the Al-Si system and the technological parameters of the L-PBF of the modified housing of the gear reducer are established. Using the finite element method (FEM) the L-PBF process was numerically simulated and the technological modes for synthesis of the AlSi10Mg alloy powder were optimized. With the help of a serial 3D printer ProX320DMP, the prototype of a gear housing was manufactured.

The Mechanical Behavior of a Mammalian Lung Alveolar Duct Model

1995 ◽  
Vol 117 (3) ◽  
pp. 254-261 ◽  
Author(s):  
E. Denny ◽  
R. C. Schroter
Keyword(s):  
Experimental Data ◽  
Mechanical Properties ◽  
Collagen Fiber ◽  
Fiber Bundles ◽  
Published Data ◽  
The Finite Element Method ◽  
Dependent Relationship ◽  
Alveolar Duct ◽  
Mammalian Lung ◽  
Air Liquid Interface

A model for the mechanical properties of an alveolar duct is analyzed using the finite element method. Its geometry comprises an assemblage of truncated octahedral alveoli surrounding a longitudinal air duct. The amounts and distributions of elastin and collagen fiber bundles, modeled by separate stress-strain laws, are based upon published data for dogs. The surface tension of the air-liquid interface is modeled using an area-dependent relationship. Pressure-volume curves are computed that compare well with experimental data for both saline-filled and air-filled lungs. Pressure-volume curves of the separate elastin and collagen fiber contributions are similar in form to the behavior of saline-filled lungs treated with either elastase or collagenase. A comparison with our earlier model, based upon a single alveolus, shows the duct to have a behavior closer to reported experimental data.

New fourth-order convergent algorithm for analysis of trusses with material and geometric nonlinearities

2021 ◽  
pp. 030932472110005
Author(s):  
Luiz Antonio Farani de Souza ◽  
Douglas Fernandes dos Santos ◽  
Rodrigo Yukio Mizote Kawamoto ◽  
Leandro Vanalli
Keyword(s):  
Fourth Order ◽  
Nonlinear Behavior ◽  
Path Following ◽  
System Of Nonlinear Equations ◽  
The Finite Element Method ◽  
Step Method ◽  
Geometric Nonlinearities ◽  
Standard Procedures ◽  
Elastoplastic Constitutive Model ◽  
Convergent Algorithm

This paper presents a new algorithm to solve the system of nonlinear equations that describes the static equilibrium of trusses with material and geometric nonlinearities, adapting a three-step method with fourth-order convergence found in the literature. The co-rotational formulation of the Finite Element Method is used in the discretization of structures. The nonlinear behavior of the material is characterized by an elastoplastic constitutive model. The equilibrium paths with limit points of load and displacement are obtained using the linearized Arc-Length path-following technique. The numerical results obtained with the free program Scilab show that the new algorithm converges faster than standard procedures and modified Newton-Raphson, since the approximate solution of the problem is obtained with a smaller number of accumulated iterations and less CPU time. The equilibrium paths show that the structures exhibit a completely different behavior when the material nonlinearity is considered in the analysis with large displacements.

scholarly journals Simulative investigation of ring creep on a planetary bearing of a wind turbine gearbox

2021 ◽  
Author(s):  
Jonas Gnauert ◽  
Felix Schlüter ◽  
Georg Jacobs ◽  
Dennis Bosse ◽  
Stefan Witter
Keyword(s):  
Experimental Data ◽  
Finite Element Method ◽  
Sensitivity Analysis ◽  
Planetary Gear ◽  
The Finite Element Method ◽  
Relative Movement ◽  
Wind Turbine Gearbox ◽  
Interference Fit ◽  
Planetary Gears ◽  
Module Coefficient

AbstractWind turbines (WT) must be further optimized concerning availability and reliability. One of the major reasons of WT downtime is the failure of gearbox bearings. Some of these failures occur, due to the ring creep phenomenon, which is mostly detected in the planetary bearings. The ring creep phenomenon describes a relative movement of the outer ring to the planetary gear. In order to improve the understanding of ring creep, the finite element method (FEM) is used to simulate ring creep in planetary gears. First, a sensitivity analysis is carried out on a small bearing size (NU205), to characterize relevant influence parameters for ring creep—considered parameters are teeth module, coefficient of friction, interference fit and normal tooth forces. Secondly, a full-scale planetary bearing (SL185030) of a 1MW WT is simulated and verified with experimental data.

Size Error and Modification of V-Groove in Thermal Microimprint

2013 ◽  
Vol 575-576 ◽  
pp. 543-549
Author(s):  
Hai Xiong Wang ◽  
Ji Bin Li ◽  
Yong Hu Lv
Keyword(s):  
Experimental Data ◽  
Influencing Factors ◽  
Elastic Recovery ◽  
Optical Devices ◽  
Technological Parameters ◽  
Polymer Microstructure ◽  
Promising Technology ◽  
Size Accuracy ◽  
Polymer Viscoelasticity

Thermal microimprint is a promising technology for polymer microstructure, so it is used to form V-groove on the surface of optical devices. However, it is difficult to control the size accuracy of V-groove because of the elastic recovery of polymer. In order to solve the problem, the influencing factors on the polymer elastic recovery were firstly analyzed in this article. Then, it was proposed that the embossment height of mold should be modified according to the depth of V-groove and the modifier formulas should be constructed based on the theory of polymer viscoelasticity. In the end, the optimal technological parameters of thermal microimprint were obtained through the thermal imprint experiments, and the embossment height of the mold after modification was calculated according to the experimental data, and thus a new mold was produced as to verify the accuracy of the modifier formulas. The results showed that the approach of modification could not only ensure dimension accuracy of V-groove, by keeping the error within 1μm, but also shorten the imprint time, consequently the efficiency of thermal microimprint would be improved.

scholarly journals Modelling the Characteristics of Ring-Shaped Magnetoelastic Force Sensor in Mohri’s Configuration

Sensors ◽  
2020 ◽  
Vol 20 (1) ◽  
pp. 266 ◽  
Author(s):  
Anna Ostaszewska-Liżewska ◽  
Roman Szewczyk ◽  
Peter Raback ◽  
Mika Malinen
Keyword(s):  
Experimental Data ◽  
High Sensitivity ◽  
Force Sensor ◽  
Inhomogeneous Distribution ◽  
The Finite Element Method ◽  
The Core ◽  
Magnetoelastic Effect ◽  
Proposed Model ◽  
Distribution Of Stresses ◽  
Good Agreement

Magnetoelastic force sensors exhibit high sensitivity and robustness. One commonly used configuration of force sensor with a ring-shaped core was presented by Mohri at al. In this configuration force is applied in the direction of a diameter of the core. However, due to inhomogeneous distribution of stresses, model of such sensor has not been presented yet. This paper is filling the gap presenting a new method of modelling the magnetoelastic effect, which is especially suitable for the finite element method. The presented implementation of proposed model is in good agreement with experimental data and creates new possibilities of modelling other devices utilizing magnetoelastic effect.

scholarly journals Elastic, Mechanical, and Phonon Behavior of Orpiment Arsenic Trisulfide under Pressure

2020 ◽  
Vol 2020 ◽  
pp. 1-6
Author(s):  
Liwu Jiang ◽  
Meiling Wu ◽  
Peng Shi ◽  
Chuanhui Zhang
Keyword(s):  
Experimental Data ◽  
High Temperature ◽  
Force Field ◽  
Elastic Constants ◽  
Phonon Dispersion ◽  
Geometry Optimization ◽  
Elastic Parameters ◽  
Arsenic Trisulfide ◽  
High Temperature And Pressure ◽  
Temperature And Pressure

Arsenic trisulfide (As2S3) has been found to be an excellent glass former at high temperature and pressure. However, there is still some scarcity for the elastic and phonon behavior of the orpiment phase. By using the Dreiding force field of the geometry optimization computations, we investigated the elastic constants, mechanical moduli, and the phonon dispersion of orpiment As2S3 under the pressure from 0 to 5 GPa. Some results of the elastic parameters of orpiment-As2S3 at 0 GPa are consistent with the experimental data. The phonon dispersions for orpiment As2S3 under pressure are also reasonable with previous calculations.

Theoretical elastic tensile behavior of muscle fiber bundles in traumatic loading events

2019 ◽  
Vol 69 ◽  
pp. 184-190 ◽  
Author(s):  
Atsutaka Tamura ◽  
Jun-ichi Hongu ◽  
Takeo Matsumoto
Keyword(s):  
Muscle Fiber ◽  
Tensile Behavior ◽  
Fiber Bundles

scholarly journals Experimental Investigation of the Flow Field in the Vicinity of an Oscillating Wave Surge Converter

2020 ◽  
Vol 8 (12) ◽  
pp. 976
Author(s):  
Moisés Brito ◽  
Rui M. L. Ferreira ◽  
Luis Teixeira ◽  
Maria G. Neves ◽  
Luís Gil
Keyword(s):  
Experimental Data ◽  
Boundary Layer ◽  
Mass Transfer ◽  
Flow Field ◽  
Nonlinear Behavior ◽  
Front Face ◽  
Regular Wave ◽  
Turbulent Field ◽  
Analytical Results ◽  
Power Capture

The main objective of this paper is to characterize the flow field on the front face of an oscillating wave surge converter (OWSC) under a regular wave. For this purpose, the longitudinal and vertical velocity components were measured using an Ultrasonic Velocity Profiler (UVP). In order to explain the main trends of the OWSC’s dynamics, the experimental data were firstly compared with the analytical results of potential theory. A large discrepancy was observed between experimental and analytical results, caused by the nonlinear behavior of wave-OWSC interaction that determine the turbulent field and the boundary layer. The experimental velocity field shows a strong ascendant flow generated by the mass transfer over the flap (overtopping) and flow rotation generated by the beginning of the flap deceleration and acceleration. These features (overtopping and flow rotation) have an important role on the power capture of OWSC and, therefore, analytical results are not accurate to describe the complex hydrodynamics of OWSC.

Macro/Meso/Micro Elastic-Viscoplastic Analysis of Plain-Woven Laminates Using Homogenization Theory

2014 ◽  
Vol 626 ◽  
pp. 365-371 ◽  
Author(s):  
Kohei Oide ◽  
Tetsuya Matsuda
Keyword(s):  
Experimental Data ◽  
Constitutive Equation ◽  
Glass Fiber ◽  
Present Method ◽  
Time Dependent ◽  
Homogenization Theory ◽  
Fiber Bundles ◽  
Woven Glass Fiber ◽  
Good Agreement

In this study, macro/meso/micro elastic-viscoplastic analysis of plain-woven laminates is conducted based on a homogenization theory for nonlinear time-dependent composites. For this, a plain-woven laminate is modeled with respect to three scales by considering the laminate as a macrostructure, fiber bundles (yarns) and a matrix in the laminate as a mesostructure, and fibers and a matrix in the yarns as a microstructure. Then, an elastic-viscoplastic constitutive equation of the laminate is derived by dually applying the homogenization theory for nonlinear time-dependent composites to not only the meso/micro but also the macro/meso scales. Using the present method, the elastic-viscoplastic analysis of a plain-woven glass fiber/epoxy laminate subjected to on-and off-axis loading is performed. It is shown that the present method successfully takes into account the effects of viscoplasticity of the epoxy in yarns on the elastic-viscoplastic behavior of the plain-woven GFRP laminate. It is also shown that the results of analysis are in good agreement with experimental data.

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