An improved semi-discrete approach for simulation of 2.5D woven fabric preforming

Analysis of the Blank Holder Force Effect on the Preforming Process Using a Simple Discrete Approach

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.554-557.441 ◽

2013 ◽

Vol 554-557 ◽

pp. 441-446 ◽

Cited By ~ 13

Author(s):

Walid Najjar ◽

Xavier Legrand ◽

Philippe Dal Santo ◽

Damien Soulat ◽

Serge Boude

Keyword(s):

Process Parameters ◽

Material Behavior ◽

Woven Fabric ◽

Physical Parameters ◽

Angle Distribution ◽

Forming Process ◽

Plane Shear ◽

Blank Holder ◽

Moulding Process ◽

Discrete Approach

Simulation of the dry reinforcement preforming, first step of the Resin Transfer Moulding process, become necessary to determine the feasibility of the forming process, compute the fiber directions in the final composite component, and optimize process parameters during this step. Contrary to geometrical approaches, based on fishnet algorithms, finite element methods can take into account the actual physical parameters, the real boundary conditions and the mechanical behavior of the textile reinforcement. The fabric can be modeled either as continuum media with specific material behavior [5, 6], or using discrete structural elements to describe the textile structure at the mesoscopic scale. A semi-discrete approach, which is a compromise between the above continuous and discrete approaches, is also used for simulation. A discrete approach for the simulation of the preforming of dry woven reinforcement has been proposed and presented in a previous paper. This modelling is based on a “unit cell” formulated with elastic isotropic shells coupled to axial connectors. The connectors, which replace bars or beams largely studied in other discrete approaches, reinforce the structure in the yarn directions and naturally capture the specific anisotropic behavior of fabric. Shell elements are used to take into account the in-plane shear stiffness and to manage contact phenomena with the punch and die. The linear characteristic of the connectors, has been extended to a non linear behaviour in the present paper to better account for fabric undulation. Using this numerical model, we propose, in this work to study the effect of process parameters on the woven fabric deformation during the performing step. The emphasis will be placed on the analysis of the influence of the blank holder pressure on the shear angle distribution.

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Meso-Macro Simulations of Textile Composite Forming

ASME 2008 International Manufacturing Science and Engineering Conference, Volume 1 ◽

10.1115/msec_icmp2008-72382 ◽

2008 ◽

Cited By ~ 1

Author(s):

Nahiene Hamila ◽

Philippe Boisse ◽

Sylvain Chatel

Keyword(s):

Woven Fabric ◽

Textile Composite ◽

Multiscale Materials ◽

Discrete Approach ◽

Resin Injection ◽

Composite Forming ◽

Unit Cells ◽

Forming Simulations ◽

Validation Tests ◽

Textile Fabric

Composite textile reinforcement draping simulations aid in determining the processing conditions for a quality part and in finding the positions of the fibers after forming. This last point is essential for the structural computations of the composite part and for resin injection analyses in the case of LCM processes. Because the textile composite reinforcements are multiscale materials, continuous (macro) approaches and discrete (meso) approaches that model the yarns have been developed. The finite element that is proposed in this paper for textile fabric forming is composed of woven unit cells. The mechanical behaviour of these is analyzed by 3D computations at the mesoscale. The warp and weft directions of the woven fabric can be in an arbitrary direction with respect to the direction of the element side. This is very important in the case of multi-ply deep drawing and when using remeshing. The element is efficient because it is close to the physics of the woven cell while avoiding the very large number of unknowns in the discrete approach. A set of validation tests and forming simulations on single-ply and multi-ply fabrics is presented and shows the efficiency of the approach.

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Mikania micrantha mixed woven fabric for quick blood clotting and wound healing

Journal of Textile Engineering & Fashion Technology ◽

10.15406/jteft.2020.06.00252 ◽

2020 ◽

Vol 6 (5) ◽

Author(s):

Shaikh Md Mominul Alam ◽

Shilpi Akter ◽

Md Lutfor Rahman

Keyword(s):

Wound Healing ◽

Blood Clotting ◽

Woven Fabric ◽

Excessive Bleeding ◽

Sustainable Operations ◽

Environment Friendly ◽

Mikania Micrantha ◽

Leaf Powder ◽

Medical Textile ◽

Dressing Materials

The aim of this paper is to introduce novel dressing with Mikania Micrantha for quick blood clotting and wound healing. When epidermis of human skin is cut or scrapped, sometimes too much bleeding occurs. Excessive bleeding may cause death, if bleeding is not stopped immediately. To promote blood clotting & wound healing natural based bio materials are still insufficient in medical textile sector. To fill up this scarcity, woven fabric treated with Mikania micrantha leaf juice & leaf powder was examined. M. micrantha exhibits good blood clotting time in comparison with available dressing materials. Woven fabric (bandage) that contains M. micrantha can be used for cut wounds healing purpose. The experiments were carried out in environment friendly way which indicates the production & processing of these dressing materials can have enormous contribution to sustainable operations and products.

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