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This paper aims to show a resin-flowing model based on Darcy’s law to display the flowing properties of prepreg during lamination. The conformity between the model and experimental results demonstrates that it can provide a guideline on print circuit board (PCB) lamination.

Based on the theoretical derivations of Darcy’s law, this paper made an analysis on the flow of prepreg in the pressing process, according to which a theoretical model, namely, resin-flowing model was further formulated.

This paper establishes a resin-flowing model, according to which two experiment-verified conclusions can be drawn: first, the resin-flowing properties of material A and B can be improved when the heating rate is between 1.5 and 2.5 min/°C; second, increased pressure gradient can add the amount of flowing resin, mainly featured by increasing pressure and reducing filled thickness of prepreg.

This model provides guidance on setting lamination parameters for most kinds of prepregs and decreasing starvation risk for PCB production.

The purpose of the present paper is to describe the modeling, analysis and simulations for the resin transfer molding (RTM), manufacturing process with particular emphasis on the sensitivity analysis for non‐isothermal applications.

For the manufacturing of advanced composites via RTM, besides the tracking of the resin flow fronts through a porous fiber perform, the heat transfer and the resin cure kinetics play an important role. The computational modeling is coupled multi‐disciplinary problem of flow‐thermal‐cure. The paper describes the so‐called continuous sensitivity formulation via the finite element method for this multi‐disciplinary problem for process modeling of composites manufactured by RTM to predict, analyze and optimize the manufacturing process.

Illustrative numerical examples are presented for two sample problems which include examination of sensitivity parameters for the case of material and geometric properties, and boundary conditions including fill time sensitivity analysis. The results indicate that the proposed formulations serve a useful role for the design and optimization of the RTM manufacturing process, thereby, avoiding heuristic trial‐and‐error methods.

The paper restricts attention to constant properties and extensions to non‐linear thermophysical properties will serve as an added benefit.

The present efforts significantly impact the design/optimization process in the process modeling of composites manufactured by RTM.

To the authors' knowledge, this is the first time that continuous sensitivity analysis is done for non‐isothermal considerations in RTM.

This paper is a critical comparison of the currently used methods to test prepregs which do not describe to a sufficient extent the flow behaviour of a prepreg resin during the pressing process. The new test method introduced herein is a characterisation of the viscosity of the resin melt. International standardisation of this test method is recommended.

The purpose of this paper is to investigate thermally and hydrodynamically fully developed convection in a duct of rectangular cross-section containing a porous medium and fluid layer.

The Darcy–Brinkman–Forchheimer flow model is adopted. A finite difference method of second-order accuracy with the Southwell-over-relaxation method is deployed to solve the non-dimensional momentum and energy conservation equations under physically robust boundary conditions.

It is found that the presence of porous structure and different immiscible fluids exert a significant impact on controlling the flow. Graphical results for the influence of the governing parameters i.e. Grashof number, Darcy number, porous media inertia parameter, Brinkman number and ratios of viscosities, thermal expansion and thermal conductivity parameters on the velocity and temperature fields are presented. The volumetric flow rate, skin friction and rate of heat transfer at the left and right walls of the duct are also provided in tabular form. The numerical solutions obtained are validated with the published study and excellent agreement is attained.

To the author’s best knowledge this study original in developing the numerical code using FORTRAN to assess the fluid properties for immiscible fluids. The study is relevant to geothermal energy systems, thermal insulation systems, resin flow modeling for liquid composite molding processes and hybrid solar collectors.

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder metallurgy and composite material processing are briefly discussed. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for 1994‐1996, where 1,370 references are listed. This bibliography is an updating of the paper written by Brannberg and Mackerle which has been published in Engineering Computations, Vol. 11 No. 5, 1994, pp. 413‐55.

A simplified approach for estimating weld lines, vent locations and fill times for resin transfer molding applications in non‐planar geometry is presented. The molding parts are treated as polyhedral spaces for which the concept of Voronoi diagram and shortest paths is utilized to predict the formation of weld lines, location of vents and filling times. The approach is based purely on geometrical considerations and on previously established observations that it is possible to treat the resin flow inside the mold as partly radial and partly channel‐like. The proposed procedure is geared towards software implementation, but it enables one to gain more insight into the process before detailed and time‐consuming calculations are attempted.

The purpose of this paper is to present a numerical and mathematical model of a moulding process of a dry electrical transformer. Moreover, the calculated results are reported and compared with experimental measurements.

An experimental rig, for carrying out and monitoring a moulding process, has been designed and built. Two experiments were preformed. First was an isothermal experiment in which an analog liquid was used. The second experiment was a non‐isothermal one in which an epoxy resin was used. For the rig geometry, the numerical mesh, with the use of the commercial code Gambit, was built. All necessary physical properties, including viscosity, surface tension and contact angle of fluids used in the experiments were measured.

The Euler approach for modelling multiphase flow with a free surface is addressed in the presented work. Comparison of the computational results with measurements on the designed experimental rig revealed good agreement. Comparison was carried out through measurements of free surface characteristic features captured with a digital camera and through temperature measurements for the nonisothermal case. Richardson extrapolation method was successfully applied to estimate the numerical discretisation error, proving that a grid independent solution was obtained.

This paper is useful for researchers and industrialists involved in the modelling of moulding processes, giving guidance on the available mathematical models appropriate for this kind of problem. Moreover, it provides valuable information as to how to perform validation and verification procedures for such real‐life processes.

The resin transfer molding process for composites manufacturing consists of either of two considerations, namely, the fluid flow analysis through a porous fiber preform where the location of the flow front is of fundamental importance, and the combined flow/heat transfer/cure analysis. In this paper, the continuous sensitivity formulations are developed for the process modeling of composites manufactured by RTM to predict, analyze, and optimize the manufacturing process. Attention is focused here on developments for isothermal flow simulations, and various illustrative examples are presented for sensitivity analysis of practical applications which help serve as a design tool in the process modeling stages.

The purpose of this paper is to investigate the effects of structural parameters of fabric on thermal insulation properties of the coated fabric.

The authors established a numerical model for the ablation of silicone resin-coated fabric under high heat flow, and the simulation results have been validated by quartz lamp ablation experiment. The model was used to investigate the effects of structural parameters of glass fiber fabrics on the heat transfer process of the coated fabric.

The numerical values were in agreement with the experimental values. The thermal insulation of the coated glass fiber fabric was better than coated carbon fabric. Thermal insulation performance of the coated glass fiber fabrics was in order plain < 2/1 twill < 3/3 twill < 5/3 stain fabric. Increasing the warp density, from 100 to 180 ends/10 cm, the temperature of the back surface of the coated glass fiber fabric was reduced from 601°C to 553°C. Thermal insulation performance dramatically increased as yarn fineness went from 129 to 280 tex, and the temperature difference was 63°C.

In the ablation process, to simplify the calculation, the combustion reaction of silicone resin was ignored, which can be added in the future research.

This paper provides the ablation model of the silicon-coated fabric based on the 3D geometry model to explore the influence of the structural parameters of coated glass fiber fabric on its thermal protection performance.

Most stereolithography systems use a blade to accomplish the recoating of the part being built with a new layer of resin. States the problems associated with this technique and describes experiments conducted to determine how recoating parameters should be controlled. Differentiates between recoating over an entirely solid substrate and over one consisting of solid and liquid, i.e. the “trapped volume” condition. Discusses parameter control for both of these conditions. Concludes that recoating is an important part of the stereolithography process which must be optimized to ensure accuracy of prototype parts.