Figure 10 Effect of throughput on
the resin profile on the full-flight screw.
An in situ measurement of the resin profile to evaluate the resin
profile more quantitatively is indispensable because the specific volume
of the resin is temperature dependent and the complete resin profile of
the molten resin cannot be estimated from the solid-state of the
semi-crystallized resin profile. Thus, an in situ laser light section
method for the measurement of the resin profile was developed in our
previous study.27 Figure 10 shows the resin profiles
of the full-flight screw observed at the port indicated in Figure 4. In
our previous study, the resin profile fluctuated with time. The resin
profile in Figure 10 is the profile that corresponds to the
time-averaged degree of fill. The numerical simulation results are
obtained from the contour plot. Interestingly, both the experimental and
simulation resin profiles of the first and second rows (throughput from
0.011 to 0.022 kg/h/rpm) agree well with each other. In the third row
(throughput 0.027 to 0.034 kg/h/rpm), the experimental results show a
smaller resin profile than the simulation.