Thursday, December 6, 2018 11am ET

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Logistic information

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Agenda

  1. Prototype testing results (Ernie)
  2. Costing the spectrometer
  3. Rational for structural support for the coils
  4. He vs. air
  5. Upcoming meetings

Minutes

Attendance: Ernie, Jim, Jason, Juliette, Roger, Kent, Ruben, Dave, Probir, Sandesh, KK, Robin

  1. Prototype testing results
    1. 37 C predicted - 32 C was the result
    2. 10 turn coil 30 C expected in another coil: 1938 A (reading meter off front of supply)
    3. flow meters - tevalin mech. accuracy +/-2% full scale, pressure gauges +/- 1%
    4. IR and gauges gave the same results
      1. 24.1 C at little triangle
      2. you can see the Delta T from inside to outside
      3. stresses across coil - Delta T of 30 C
    5. Left on for ~2 hours
    6. Chiller would climb over time (chiller issue not coil issue)
    7. How much overhead is there - function of the water flow
      1. is there thermal runaway? At what point would it be?
      2. 70 C on coil - never get close to that - depends on inlet temperature
      3. will be interlocked - never get to runaway conditions
      4. what about a failed sensor - coil gets plugged up?
      5. multiple redundant interlocks meters for DeltaT, flow rate, voltage (R changing)
        1. weren't having flow meters on every cooling path
        2. could have a temperature monitor on each
    8. mechanical temp gauges mounted around; very close to the IR gauge
    9. everything referenced to inlet coolant temperature
    10. watch exactly where the conductor goes
    11. How long did it take to reach thermal equilibrium? - 20-30 minutes
    12. Emissivity settings (0.95) - set as well as bandwidth - compare to reference
      1. had a confirmation measurement with the mechanical gauge
    13. 1938 A - long coil - flow 20% low
      1. but DeltaT is smaller
      2. no radiation in Hall in the calculations
      3. still haven't processed everything
      4. 0.7 m^2, 500 W seems low compared to what was seen
    14. coil was not uniform temperature
    15. epoxy temperature - all thermal measurements on epoxy surface
    16. How do we want to use this?
      1. Put a check mark on water flow, DeltaT,
      2. Diagram or sketch
      3. summary of data
      4. need a written report
    17. If you summarize results
      1. table of data
      2. diagram
      3. Ernie's calculations
      4. Ruben is not going to model this setup
        1. don't need to do a full simulation
        2. not a full CFD, but analytical estimates get pretty darn close
    18. additional tests of prototype until early to mid-January
      1. rigidity, flatness (don't have laser trackers)
      2. people can go to observe
      3. don't want to power all coils in series because of various issues
      4. write-up complete before December meeting
  2. Costing the spectrometer
    1. move to a separate, standalone meeting
  3. Rational for structural support for the coils - Tolerance question - should look at the effect of individual pieces of the coil
    1. tolerance should depend on z and radius - need to look at deformations
    2. azimuthal shift in one of the coils is very benign - we'd end up hitting adjacent coils
    3. mechanical, dose on coils and stray fields in beamline
    4. they are setting down their tolerances in a document
    5. tolerances chart from Thia about how things relate to each other
    6. Allen produced it from the CAD
    7. Q2 measurements - 2mm between energizing on and off - don't want a Q2 measurements each time
    8. 3 supports - normal to their plane if the coil tips it will move the whole coil
    9. braces between the coils -
  4. What questions need to be answered at which stage?
    1. how much has been done?
    2. how much work still needs to be done?
    3. those numbers have got to go up?
    4. still need some iterations
    5. what's the goal? Fully vetted cost in January
      1. Magnet review week of the 28th of January
        1. prototype (manufacturability, water cooling calculations) - how they will be used
        2. segmented coil design vs. hybrid
          1. mechanical support - more degrees of freedom for the segmented
          2. CAD drawings - JLAB has the drawings
        3. review questions from the last director's reviews
          1. CD0 - presented a magnet, get questions
          2. need a plan to answer - timeframe and resources available
      2. Engineering meeting to go through the costing done by JLAB
        1. budgetary bids for everything that was designed
        2. vacuum chamber, coils, supports (budgetary bids by companies)
        3. week of the 17th - JLAB and MIT get together - afternoon of 17th, morning of 18th
        4. Tuesday the 18th w/ JLAB at 9:30am
      3. JLAB may be asked about upper ceiling of the MOLLER cost end of January
        1. may request funds for MOLLER
        2. enough to make sure cost doesn't explode?
      4. Director's Review (late spring - March, April)
        1. new review of whole project
        2. do we have a defendable coil
        3. preliminary cost
      5. CD1 review
        1. what do we need for that?
  5. He vs. air
    1. work for another 10 days on physics
    2. don't have a physics design for He
    3. haven't thought about all the physics implications
    4. week of 17th - what engineering
  6. Upcoming meetings
    1. Costing meeting December 17-18, 2018 at JLAB
    2. Magnet review week of the 28th of January
    3. Director's Review late March to mid-April
    4. CD1 Review



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