Mold filling and curing analysis in liquid composite molding

Abstract

Non-isothermal mold filling and curing experiments of liquid composite molding were carried out in this work. To compare the experimental results with a previously developed numerical simulation model, measurements of volumetric heat transfer coefficient between the resin and the fiber, and characterization of resin kinetics and rheological changes were also conducted. Combined with the previously measured fiber preform permeability, the numerical model provided a good prediction of temperature profiles during molding for a polyurethane/glass fiber composite.

Non‐isothermal ‘2‐D flow/3‐D thermal’ developments encompassing process modelling of composites: flow/thermal/cure formulations and validations

“…The heat transfer, however, still has to be treated in three dimensions because heat convection in the planar direction and heat conduction in the gapwise direction are both signiÿcant [27]. In this paper, theoretical details of a modiÿed methodology termed as '2-D ow= 3-D thermal' are presented.…”

“…Experiment #1 [27] The experiment performed by Lin et al [27] involves the injection of mixed urethane resin into the circular cavity preplaced with OCF M8610 random ÿbre mat. The mold cavity has an inner radius of 0:635 cm, an outer radius of 20 cm, and a gap thickness of 1.27 cm.…”

“…The mold cavity has an inner radius of 0:635 cm, an outer radius of 20 cm, and a gap thickness of 1.27 cm. According to Lin et al [27], the molds were kept at a constant temperature of 120 • C and the mixed urethane resin was maintained at 41…”

Heat Transfer in Porous Media

“…This shows the importance of heat transfer equations in the non-isothermal flow in porous media. Generally, the energy balance equations can be derived using two different approaches: (1) two-phase or thermal non-equilibrium model [2][3][4][5][6] and (2) local thermal equilibrium model [7][8][9][10][11][12][13][14][15][16][17][18]. There are two different energy balance equations for two phases (such as resin and fiber in liquid composite molding process) separately in the two-phase model, and the heat transfer between these two equations occur via the heat transfer coefficient.…”

“…In the thermal equilibrium model, we assume that the phases (such as resin and fiber) reach local thermodynamic equilibrium. Therefore, only one energy equation is needed as the thermal governing equation, [3,5]. Firstly, we consider the heat transfer governing equation for the simple situation of isotropic porous media.…”