Mechanical analysis on changing cross-sectional segment of fibre band in condensing zone in compact spinning

In this study, a novel concept has been developed as a cyclical spacing-change method to produce periodic varied structural composite yarn. Geometrical analysis indicated that the cyclical change of spacing between filaments and the strand altered the yarn formation zone shapes from corefil to sirofil, causing cyclic yarn structure variations from the hairy core–sheath (corefil section) to the smooth spiral filament wrapping (sirofil section). A mechanical analysis revealed the corefil section with more twists was thinner than the sirofil section with fewer twists. Specifically, the cross-sectional diameter performed gradual periodic changes from the thick sirofil section to the thin corefil section. Then, an eccentric godet wheel device was used to conduct confirmatory experiments. Besides validating the theoretical analysis, the experimental results also showed that the novel concept yarn had the minimum hairiness and medium irregularity and strength after comparisons with sirofil and corefil yarns.

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Stress-Swelling Finite Element Modeling of Cervical Response With Homeostatic Collagen Fiber Distributions

Journal of Biomechanical Engineering ◽

10.1115/1.4045810 ◽

2020 ◽

Vol 142 (8) ◽

Author(s):

Kun Gou ◽

Heiko Topol ◽

Hasan Demirkoparan ◽

Thomas J. Pence

Keyword(s):

Mechanical Property ◽

Collagen Fiber ◽

Opposite Effect ◽

Mechanical Analysis ◽

Ground Substance ◽

Sectional Area ◽

Cervical Tissue ◽

Cross Sectional ◽

Collagen Orientation ◽

Property Change

Abstract During pregnancy, the cervix experiences significant mechanical property change due to tissue swelling, and to ongoing changes in the collagen content. In this paper, we model how these two effects contribute to cervical deformation as the pressure load on top of the cervix increases. The cervix and its surrounding supporting ligaments are taken into consideration in the resulting mechanical analysis. The cervix itself is treated as a multilayered tube-like structure, with layer-specific collagen orientation. The cervical tissue in each layer is treated in terms of a collagen constituent that remodels with time within a ground substance matrix that experiences swelling. The load and swelling are taken to change sufficiently slowly so that the collagen properties at any instant can be regarded as being in a state of homeostasis. Among other things, the simulations show how the luminal cross-sectional area varies along its length as a function of pressure and swelling. In general, an increase in pressure causes an overall shortening of the lumen while an increase in swelling has the opposite effect.

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Effect of Doped Glass Fibers on Tensile and Shear Strengths and Microstructure of the Modified Shotcrete Material: An Experimental Study and a Simplified 2D Model

Minerals ◽

10.3390/min11101053 ◽

2021 ◽

Vol 11 (10) ◽

pp. 1053

Author(s):

Cunli Zhu ◽

Nan Zhou ◽

Yaben Guo ◽

Meng Li ◽

Qiangqiang Cheng

Keyword(s):

Fly Ash ◽

Mechanical Performance ◽

Glass Fibers ◽

Testing Machine ◽

Mechanical Analysis ◽

Sand Fly ◽

Tensile Testing Machine ◽

Cross Sectional ◽

Research Findings ◽

Doped Glass

Shotcrete material has found extensive applications as a reinforcing material in the engineering sector. This study examined the effect of doped glass fibers on the mechanical performance of the modified shotcrete material composed of aeolian sand, fly ash, cement, quicklime, and doped glass fibers. Its tensile and shear strengths values were experimentally determined via a WAW-1000D computerized hydraulic universal tensile testing machine. Its microstructure was analyzed via a size analyzer, scanning electron microscope (SEM), and X-ray diffractometer (XRD). A 2D simplified mechanical model was elaborated to reflect the influence mechanism of the doped glass fibers on the mechanical performance of the modified shotcrete material. The experimental and mechanical analysis results indicated that, at the macroscopic scale, the experimental tensile and shear strengths of the shotcrete material doped with glass fibers were significantly higher than those of the undoped shotcrete material (by up to 310% and 596%, respectively). These results were in concert with the proposed model predictions, where the compound stresses in the shotcrete material were derived as the sum of the stress borne by the shotcrete material itself and the bridging stress exerted by the glass fibers. At the microscopic scale, SEM observations also revealed that the glass fibers were intertwined with each other and tightly enveloped by the shotcrete material particles within the modified shotcrete specimens, connecting the particles of different components into a whole and improving the overall mechanical strength. In addition, the relationships of the compound stress of the shotcrete material vs. embedment length, embedment angle, and cross-sectional area of the glass fibers were established. The research findings are considered instrumental in clarifying the mechanism by which the glass fibers influence the mechanical performance of shotcrete materials and optimize their solid waste (fly ash and quicklime) utilization.

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Mechanical modeling of an arc-shaped suction slot for compact spinning and analysis of additional twists

Textile Research Journal ◽

10.1177/0040517517723029 ◽

2017 ◽

Vol 88 (21) ◽

pp. 2499-2505 ◽

Cited By ~ 1

Author(s):

Ting Fu ◽

Jianping Yang ◽

Guangwei Cheng ◽

Nanliang Chen ◽

Yiping Qiu

Keyword(s):

Frictional Coefficient ◽

Mechanical Analysis ◽

Curvature Radius ◽

Model Design ◽

Mechanical Modeling ◽

Obvious Effect ◽

Runge Kutta Method ◽

Compact Spinning ◽

Suction Slot ◽

Fibrous Strand

In this study, an arc-shaped suction slot was designed for a pneumatic compact spinning system with a lattice apron. A model was built via mechanical analysis of a fibrous strand in an arc-shaped suction slot to calculate additional twists inserted during condensing. The equations can be solved by using the Runge–Kutta method. The simulation results showed that negative pressure and frictional coefficient of the lattice apron and the fibrous strand have significant effects on additional twists of the strand in an arc-shaped slot. The curvature radius of the arc slot has some influence on the additional twists, while that of the condensing surface has no obvious effect on the additional twists. The radius of the strand may significantly influence the additional twists, but the radius of the strand itself is affected by various other factors. Spinning tests were carried out based on the model design. These results verified the additional twist model of the arc-shaped suction slot.

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Numerical Simulation on the Laser Bending of Thin Wall Tubes

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.460-461.798 ◽

2011 ◽

Vol 460-461 ◽

pp. 798-801 ◽

Cited By ~ 2

Author(s):

Nan Hai Hao ◽

Yu Ling Gai

Keyword(s):

Process Parameters ◽

Three Dimensional ◽

Mechanical Analysis ◽

Outer Diameter ◽

Thin Wall ◽

Laser Bending ◽

Cross Sectional ◽

Bending Process ◽

Mechanical Bending ◽

The Cost

Laser tube bending is a spring-back-free noncontact forming method that has received considerable attention in recent years. Compared to mechanical bending, no hard tooling, dies, or external force is used in laser bending, thus the cost is greatly reduced for small-batch production and prototyping. Some quality issues, such as cross sectional distortion and intrados protrusion exist in laser bending and have growing tendency when the tube’s wall being thinner. This paper investigates the effects of process parameters on the deformation of thin wall tube through numerical simulations and experiments. The dimensions of the tube analyzed are 32 mm in outer diameter and 0.48mm in wall thickness. A three-dimensional transient thermo-mechanical analysis using the finite element method is carried out to simulate the laser bending process with some results validated by experiments. The effects of process parameters on the deformation of thin wall tubes are discussed in detail.

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Morphometric and biomechanical parameters of tibiotarsus in different strains of broilers

Biotechnology in Animal Husbandry ◽

10.2298/bah0806053v ◽

2008 ◽

Vol 24 (5-6) ◽

pp. 53-59 ◽

Cited By ~ 1

Author(s):

Dusan Vitorovic ◽

Z. Pavlovski ◽

Z. Skrbic ◽

M. Lukic ◽

V. Petricevic

Keyword(s):

Strain Differences ◽

Experimental Period ◽

Mechanical Analysis ◽

Broiler Chicks ◽

Breaking Force ◽

Cross Sectional ◽

Cervical Dislocation ◽

Biomechanical Parameters ◽

Different Strains ◽

The Right

One hundred male and one hundred female broiler chicks from different strains : Master Gris, Red Bro, Farm Q and Hubbard Classic, were reared in conventional broler house system, during first three weeks After the third week, fattening was continued in an extensive free-range rering system. At the end of experimental period (91 days of age) 10 male and 10 female birds, of each stran, were killed by cervical dislocation and the right tibiotarsal bones were removed and used for morphological and mechanical analysis. The obtained results showed that there were statistically signifficant strain differences. Mass, length, breaking force, cross sectional area of diaphysis, medullary cavity area and cortical area, of tibiotarsal bone of Farm Q hybrid chicks were statistically signifficant lower than that of Hubbard Classic, Master Gris and Red Bro strains in both male and female chicks.

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Electro-thermal-mechanical Coupled Analysis on Two High-Current Composite Umbilical Cable Cross-sections

Journal of Offshore Mechanics and Arctic Engineering ◽

10.1115/1.4051089 ◽

2021 ◽

pp. 1-32

Author(s):

Jun Yan ◽

Qi Su ◽

Yufeng Bu ◽

Zhixun Yang ◽

Qingzhen Lu ◽

...

Keyword(s):

Cross Sections ◽

Heat Dissipation ◽

Production Systems ◽

Mechanical Analysis ◽

External Pressure ◽

Field Analysis ◽

Coupled Analysis ◽

Cross Sectional ◽

The Cross ◽

Umbilical Cable

Abstract A new type of umbilical cable named ‘strong-electricity composite umbilical cable’ is composed of electronic cables, optical cables, steel tubes and structural strengthening components. It can be regarded as a key piece of industrial equipment in subsea production systems that provide control functions, strong electric and hydraulic remote transmission. when it is oriented at a power supply with a relatively high rated voltage, power transmission will produce a lot of heat. Then, the cross-sectional temperature increases, which affects the performances of its material and mechanical responses. Therefore, electro–thermal–mechanical coupled analysis is critical for the cross-sectional design of the strong-electricity composite umbilical cable. Accordingly, a multi-physics coupled analysis was performed based on two typical umbilical cable cross-sections. Finite element models were established and subjected to electro–thermal analysis to obtain a temperature distribution of the two sections at different current capacities. Based on results of temperature field analysis, the section models were subjected to thermal–mechanical analysis. The results of the two types of analyses are compared and differences are discussed, which illustrate the multi-physics coupled effect cannot be neglected. The armored layers will relatively reduce the heat dissipation performance, but compared with the umbilical cable model without the armored layers, the model with double-armored layers is less affected by temperature, so its capacity of resistance external pressure is relatively better. The proposed coupled analysis methodology provides a new guidance for the design of the strong-electricity composite umbilical cables.

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Coupled Thermo-Elastic Analysis on Cross-Section of Umbilical Cables

Volume 5A: Pipelines, Risers, and Subsea Systems ◽

10.1115/omae2019-96195 ◽

2019 ◽

Author(s):

Jun Yan ◽

Haitao Hu ◽

Qi Su ◽

Qingzhen Lu ◽

Zhixun Yang ◽

...

Keyword(s):

Cross Section ◽

Power Transmission ◽

Mechanical Analysis ◽

Coupled Analysis ◽

Elastic Analysis ◽

Cross Sectional ◽

Static Mechanical ◽

The Cross ◽

Cross Sectional Design ◽

Umbilical Cable

Abstract Umbilical cable is composed of electronic cables, optical cables, steel tubes and structural strengthening components, which can be regarded as a key industrial equipment integrating mechanical and electronic functions. Especially, when it is oriented at the power supply with a relatively high rated voltage, the power transmission will produce a large amount of heat with the sectional temperature rising up, which impacts on the material performance and mechanical responses of the cable and even the whole umbilical. Therefore, the thermo-elastic analysis is the critical technology in the cross-sectional design of umbilical cable. Analytical and numerical methods are proposed to conduct the thermo-elastic analysis of the cross-section. Firstly, the steady-state thermal analysis of cross-section of the umbilical cable is implemented, and the thermal field distribution with different cable ampacity is obtained. Then, the thermo-elastic coupled analysis of the cross-section is presented. It is found that the results are quite different from that of static mechanical analysis, which provide a helpful guide for the design of umbilical structures.

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