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Palestine TV Test. Jason Link University of Hawaii. ANITA Collaboration Meeting at UCI 4/7/05 – 4/9/05. Objectives. To verify operation of EM flight hardware at simulated Antarctic float conditions
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Palestine TV Test Jason Link University of Hawaii ANITA Collaboration Meeting at UCI 4/7/05 – 4/9/05
Objectives • To verify operation of EM flight hardware at simulated Antarctic float conditions • To obtain information on the thermal behavior of EM flight hardware under simulated Antarctic float conditions • To provide a milestone to get EM hardware ready • To interface with NSBF on upcoming flight issues.
NSBF BEMCO Chamber • Chamber is heated by large 13 kW heating element that cannot be used while chamber is at vacuum. Can heat chamber room up to 50C prior to going to vacuum and turn off heater. • Cooling by stainless steel wall with tubing for liquid nitrogen. This can be active while chamber is at vacuum. • Typical operation for previous tests is to heat the room to 50C, go to vacuum, soak, bring the room down to -40C and soak. This takes 8-10 hours. We are constrained by the fact only NSBF personnel can operate the chamber. • Instrument can be left in the chamber overnight, but it will leak up to ~300 mBar pressure by morning and gradually approach room temperature. Erich has agreed to try and set it up so we can run one day for an extended period.
Temperature Extremes for TV Test • For thermal-vacuum testing we are primarily interested in the temperature of hardware on the thermal plate. Hardware not on the plate should not have any thermal issues at vacuum. • Kurt’s thermal modeling provides information about what temperature extremes the plate might get to during flight. • →Propose to define TV test temperature extremes based on reading of temperature sensors on thermal plate. Specifically, we will use sensors on the plate that are not near any heat-sunk hardware.
Thermal Plate – Cold Case Thermal Plate ~15C away from components
Thermal Plate – Hot Case Thermal Plate ~30C away from components
Proposed Test Plan (5 Days) • Day 1 • Verify hardware operation in chamber and record temperature after 1 hour of running • Pump down to ~5 mBar while holding thermal plate temperature to ~10-15 C. Closely monitor temperatures to verify nothing is going into thermal runaway. • Run at vacuum with thermal plate at ~10-15C for the rest of the day.
Proposed Test Plan (cont) • Day 2-4 • Heat chamber so thermal plate temperature reaches 40 C, soak for two hours, turn off BEMCO heater and go to 3-5 mBar. • While hot, powercycle system • Run until thermal plate temperature reaches ~30 C or two hours have past. • Using LN2 wall lower plate temperature to 0 C. While cold powercycle system. • Run cold until NSBF leaves. Prior to their departure ensure chamber is at 3-5 mBar and thermal plate is at 0C
Proposed Test Plan (cont) • Day 5 • While at 1 atm run the chamber cold (as measured by the exhaust out of the chamber) to -40 C with the instrument on. Run at -40 C for 2 hours. Verify operation and powercycle the system • Bring chamber up to 50 C at 1 atm (once again as measured by the exhaust out of the chamber). Run at 50 C for at least 2 hours. Verify opearation and powercycle the system
Test Plan Modifications • If we have < 5 days • Cut out a day of thermal cycling in vacuum • Cut out the thermal test • If we have > 5 days • Add in another day of thermal cycling in vacuum • Add another day to thermal test