(9) have studied viscoelastic flow simulations of various extrudate swells
by the Giesekus model (10), which is one of the differential-type constitutive equations.
It is important to understand the swell
behavior of polymer melts because the parison shape, that is, the thickness and the diameter, changes dramatically as a result of swelling, and the swell
behavior seriously depends on material properties or die dimensions.
Standard practice to achieve proper belt gauge has been to start with an opening that is too small, to run a die trial, and to recur the die assuming the die swell
extrudate expansion will remain the same in each zone.
The parison formation process is, however, difficult to predict because of unsteady viscoelastic flow, including the effects of extrudate swell
, drawdown, and shrink-back.
As alluded to above, a polymer network with a large value of [M.sub.c] is able to swell
to a higher degree than that of a network having a lower value of [M.sub.c].
The big difference of this lateral unconfined uniaxial swelling test from the swelling test of conventional consolidation equipment lies in the fact that the rock samples can swell
freely during the process of their hydrated swelling without any lateral confinement.
Therefore, uncured EPDM can be dissolved and the cured EPDM swells
in diesel fuel.
Because the groups are bound to the material, they can't move far apart, but they can force the material to swell
, says Lee.
So when the parison drops, small variations in horizontal position caused by variations in die swell
, parison swinging, or parison air pressure do not have as much effect on processing.
I tried to figure out how big the swells
were, which way the wind was blowing, and where the waves were breaking.
are--that form way out in the middle of the ocean.
When reproductive organs shift (or the prostate swells
), this can constrict normal flow of blood, lymph, and nerve connections.