Gaav. Haagh et al., TOWARDS A 3-D FINITE-ELEMENT MODEL FOR THE GAS-ASSISTED INJECTION-MOLDING PROCESS, International polymer processing, 12(3), 1997, pp. 207-215
The Gas-Assisted Injection Moulding process (GAIM) offers a number of
advantages, which are almost without exception related to the negligib
le pressure drop in the gas core of the moulded product. Accurate pred
iction of the gas distribution inside GAIM products is, however, still
a major problem to be solved. As gas penetration is governed by three
-dimensional phenomena, one has to resort to numerical simulations to
analyse the process. Therefore, a numerical model for GAIM simulations
has been developed, based on a physical, rather than on an empirical
approach. The model employs a pseudo-concentration method in order to
avoid elaborate three-dimensional remeshing, and has been implemented
in a finite element program. Simulation results for two-dimensional te
st cases representing typical GAIM situations prove that the model cov
ers most of the important aspects of gas injection. A pilot simulation
for a simple three-dimensional mould demonstrates that the model is a
ble to deal with three-dimensional GAIM. Further refinement of the mod
el will mainly concern the implementation of faster and less memory-co
nsuming solution methods.