STS-107 Daily Science Report
January 30
Mist is continuing its fast pace
of testing. Thirteen test runs were completed in the time originally
allotted for eight test runs. For one of the tests with a lean
mixture (weak flame) and a high concentration of water mist, the
video showed an impressive slow down, elongation and “wiggling”
of the flame in the misted section of the flame tube.
During one of the tests, it appeared that misting was not continuous
due to a suspected air bubble in the water delivery line. This
test point was repeated later with success. Mist has a Digital
Data Recorder (DDR) change-out scheduled since the current DDR
is filled. After the DDR change-out, Mist plans to run two more
test points before a prescheduled chamber access, during which
a new atomizer and fuel bottle will be installed.
Because the Gas Chromatograph (GC) line was deliberately kinked
in order to improve the seal of the tube, GC measurements were
not being made by Mist. (A gas chromatograph is a piece of equipment
used to determine the chemical composition of the gases used in
the experiments.) It does not seem that the absence of GC data
will negatively affect science since there is no indication of
an anomaly in the rest of the analyzed data and observations so
far.
Mist has completed a total of 16 tests using the atomizer that
produces the smallest droplet size among the three atomizers being
used. Mist was able to run additional exploratory tests using
extra-lean mixtures (very weak flames). There are indications
that these extra-lean tests are producing scientifically interesting
behavior when interacting with mist. Successful ignition of extra-lean
mixtures, even without the confirmation by the GC data of the
mixture composition, gave us confidence that the absence of GC
data does not affect Mist science negatively.
After a successful chamber access by the crew, the atomizer was
changed to produce a different droplet size. One dry test was
successfully completed and no leakage problem was encountered,
though still at the expense of giving up GC sampling. Subsequent
pump priming produced misting. Mist is now ready to start the
“wet” test points with the new atomizer. Since each
chamber access is crew intensive and takes the time equivalent
to three tests, Mist decided not to use the third atomizer (droplet
size) planned in the original matrix. Instead, more exploratory
tests will be conducted with extra-lean mixtures.
Two tests had suspected air bubbles in the water delivery line
that caused a misting problem. One test was repeated after misting
was produced again, and the other test was run dry to get baseline
flame behavior information to use for the test point.
The CVX-2 flight instrument continues
to operate well. The instrument is in the fourth critical period,
using a faster temperature ramp rate than the previous two critical
periods. CVX-2 will extend operations to include one more ramp
through the critical point before ending operations.
SAMS-FF is providing two-shift, real-time
support of MIST in the CM-2.
Orbital Acceleration Research Experiment
(OARE) will remain powered in support of MIST in the CM-2.
Quasi-steady acceleration data will be provided post-mission.
We’ve modified PDR on/off ground rules based on feedback
from MSFC data team. We need PDR to turn on 10 minutes before
MIST, then off 10 minutes after MIST run.
Mission Status Reports
January
31, 2003
January 30, 2003
January 29, 2003
January 28, 2003
January 27, 2003
January 26, 2003
January 25, 2003
January 24, 2003
January 23, 2003
January 22, 2003
January 21, 2003
January 20, 2003
