A Numerical Study of Nonisothermal Resin Flow in RTM with Heated Uniaxial Fibers

Abstract

A numerical model is developed to study the flow of a thermoset resin parallel to a unidirectional, heated fiber array, where the resin viscosity varies with temperature. Steady, incompressible flow is assumed when solving the momentum equation for the velocity parallel to the fiber tow. Resin temperatures are determined by applying a finite differencing scheme to the convective energy equation. An iterative approach is used to update the velocity, temperature, and viscosity in the flow direction. The resulting nonisothermal flow profiles are 'plug-like" with significant increases in the velocities near the fibers. Comparisons of average total flow times for isothermal and nonisothermal flows indicate that, for an epoxy resin at an initial 250C and the fibers heated to 100°C. the fill time is equivalent to the isothermal case with the resin held at a constant 50°C.

Simulation of non-isothermal filling process in vacuum assisted compression resin transfer moulding process

“…Many sophisticated models exist, which depend on the degree of cure. In this work, the cure effect is negligible since the resin temperature is much lower than 373 K. 38…”

“…Many sophisticated models exist, which depend on the degree of cure. In this work, the cure effect is negligible since the resin temperature is much lower than 373 K. 38 A local thermal equilibrium of the resin and the fibre is reasonably assumed since the resin flow is slow. The energy equation is written as follows:…”

“…The modelling input data and material properties are listed in Table 1. 3,38,41 2 Variations in a resin pressure, b preform thickness, c front progression and d resin temperature for scenario 1 For avoiding excessively long filling process, the terminated condition of the compression stage is the difference ,0?001 between the maximum V f and the minimum V f .…”