[updated with reference to data set, cleaner plot, images of chamber configuration]
StephenA, 2021.02.05
Data - cooldown 20210205 (CSV = raw, XLSX = Stephen's plots) in Box Folder [Voyager\MarinerBox\CryoEngineering\CSVlogs]
Description - 5.5 hour cooldown with data, which was then allowed to continue for a total of 96 hours (but data collection failed for the long stretch, except for a snapshot of the final state). The cold flange was below 100 K after 6 hours, and leveled off at about 80 K. The vacuum pressure was steady at 3 microTorr throughout, via a roughing line connecting the external and internal volumes (mitigated losses in external connection volume, with no areas dramatically cold to touch). The cold flange was radiating to room temperature surroundings, as the radiation shields were not installed. The cryocooler was turned on/off at the start/end of the data collection, and the in-vac heater was not powered on at all.
Images -
- IMG_8047 = starting conditions;
- IMG_8119 = intermediate conditions after 5.7 hours;
- IMG_8148 = final conditions after 96 hours;
- IMG_8232 markup = view of RTD locations on cold flange, with annotations;
- IMG_8225 = top view of cold flange and chamber configuration without radiation shields.
Plots -
- cooldown_20210205_uhv_coupled_cold_flange_first_segment - shows first 5.5 hours only;
- cooldown_20210205_uhv_coupled_cold_flange_all_time - shows all 96 hours, with data points extracted from images.
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