Microgravity data shown below is PRELIMINARY
data, subject to changes once further analysis has been performed. The
data results from CCD images captured approximately every 90 seconds during
dendrite growth as well as full-motion video. As the resolution of these
images is not sufficient to determine dendrite shape characteristics, only
the growth velocity is presented here.
The IDGE experiment is broken up into three phases. The data from each
phase is in its own table below.
Sample Material Tests
These are initial tests to assess the purity of the sample after launch,
and determine the melting temperature.
Purity is confirmed to be nominal
Melting/Freezing Temperature Measurement (on orbit)
Channel 1
35.962
Channel 2
35.967
Phase 1 This data corresponds to PVA dendrite crystals grown under "quality"
microgravity conditions. The objective during this phase of the experiment
is to obtain data points that uniformly describe
the range of supercoolings where characterization is desired. Two
cycles are run at each of 10 supercoolings.
[Data
is currently being analyzed. Information will be available soon as possible.]
Velocities based on full motion video.CCD snapshots
used when video not available
Phase 2 This data corresponds to dendrite crystals grown under "quality" microgravity
conditions. The objective during this phase of the experiment is to obtain
a large number of measurements at each of three supercoolings.
This information will be used to characterize the three-dimensional shape
of dendrite tips.
[Data is currently
being analyzed. Information will be available soon as possible.]
Velocities based on full motion video.CCD snapshots used when
video not available
Phase 3 This portion of the mission is being used to explore the transient
aspects of dendritic growth through focused used of the full-motion
video. Emphasis will also be placed on developing statistically significant
samples at two additional supercoolings in the manner of Phase 2 (above).
[Data is currently
being analyzed. Information will be available soon as possible.]
Velocities based on full motion video.CCD snapshots
used when video not available
Preliminary Plot of PVA Dendrite Tip Velocity
(USMP-4)
