23
march 2004. Bari. TVB Post Test Review.
INFN
- Bari,Pisa
SLAC
NASA
The
review started in the afternoon as all the attendees arrived at or during the
lunch hour.
The
agenda was presented by NM. TMc had a question about the behavior of the TEm
that was seen during the TVB tests at ALS.
JG
gave a thanks for the INFN work for the TVB.
SR
presented the test overview. Goal of the test as the TVB and correlation of the
model and to correlate the TCs with the thermistor.
There
were 9 cases planned and of this only 7 were performed due to time constarints.
The required temp cycles thqat were foreseen for this test were deleted by
general agreement of all parties concerned. @ balance cases in the hot, 3
balance cases in the mid and 2 cases in the cold. The test pahse was conducted
on schedule and as predicted including the test set-up. The setup description
was given - see charts for details. Some details of the TEM current consumption
which was not stable during the test.
AB
did a brief explanation of the MCM configuration of the EM tower for this test.
It was also possible/true that the power dissipation was not exactly flight
type by about 10%. The second last case was not of the nominal stablization
duration of 4 hours >= 0.1 degrees. The test log is on the BARI WEB SITE.
AT
presented the MGSE used for the TVB - see charts for details. The thermal
straps were of dry joint as there was no agreement on the final design for
flight. The grounding of the test setup is going to be very important for the
next TV test of Tower A.
NS
gave the presentation of the test article and the instrumentation. The pedigree
of the MCM in each tray will be put in the report. The +Y side wall was the most
instrumented of the 4. C05 was instrumented with TC next to the thermistor.
FG
is giving a quick talk of the results. The worst performance was of the TEM
unfortunately. The delta of the strap was found to be +/- 1 degree C with in
the accuracy of the Tcs used. The guard shield e was 0.14 and that of the base
plate is 0.67. The temp of the GS, TB and the tower were measured and was not
always under control due to difficulty in the control. The TEm temperature was
between 10 and 28 degrees C. The
thermal strap and the flexure are playing some part in the conductance. The
delta temperature between the top and bottom of the side wall is to be
presented more clearly in the report.
NM
presented the thermistor results where he had to fish out the data due to the
offset of the reading when the Tower was powered. The data was corrected by NM
and presented. A chart showing the correlation between the Tower outside
instrumentation and the thermistor data. the requirement for a flight qualified
TEm for the Tower TV tests are a must and this has to be worked with SLAC for
the schedule of the Tower A tests.
The
meeting was changed to discuss the next test of the tower A. the current test
will and should last 5 days in ALENIA time. there is a big discussion about the
thermal cycle requirements.
24
March 2004
The
discussion centered around how to proceed with the test for Tower A. One thing
that has become clear is that the next test will have to be done in another Tv
chamber where ALS will be using a chiller in a vac chamber. The tentative
design centers around the use of a passive guard shield around the Tower of the
3 options that were discussed. SLAC (JG) will do analysis to show that this is
acceptable for the thermal cycling of the Towers. The results of the analysis
will be available next friday 2 April, 2004. the baseline consideration is that
ALS will provide a chiller with the characteristics that were defined by JG
during his visit in December to ALS.
The
next test schedule was discussed and it came to light that the schedule
published by TV showed ALS tests going on in August. ALS will not be available
for any activity in August and that all test activity will have to be finished
by the end of July or completed in September. This fact was communicated to
TV/RJ by NM via email. There is no information available on the status of the
EGSE that is required for the Tray and Tower level tests. This matter will be
discussed between JG and RJ at SLAC.
There
is a thermal balance (mini) designed into the first cycle of the Tower A Tv
tests at present. There is a time constraint to this and INFN wants to complete
the tests in 5 working days (test time only). The need for this TB is 1) this
will be the first flight representative Tower to be thermally tested 2) the
correlation of the model with the EM Tower test data may not be satisfactory.
The real need for this TB will be established at the TMM correlation
presentation scheduled for second half of May. The document --408 does require
that PFM go through a TB test.
INFN hospitality was insurmountable!!