Overview of Status of Analysis, Design, Fabrication, Tests, etc.
Finished CAD mockup of first hardware iteration.
Secured access to a microgram mass balance (Professor Javier Garay)
Obtained permission to use stainless steel tubes from 156A pendulums from Professor Gravish.
Ordered control hardware (Arduino Nano, battery, etc.)
Accomplishments from Previous Week
Decided upon hardware and moved forward with purchases.
Completed heat sink selection MATLAB script (Nate G.).
Clarified project requirements even further:
Substrate surface can be insulated around the point of droplet placement, reducing needs of cooling process.
Recognized that TE cooler will require a higher current input than Arduino can source, necessitating additional hardware.
Assignments for Coming Week
Jayant Mathur
Upon delivery of control hardware, begin placing components (via CAD) and designing connections
Verify that hardware performs all required tasks (control, power supply, data collection, etc.)
Nate Goldberg
Finalize heat sink calculations
Work with Kristen to design a cold air delivery option (3D printed nozzle?)
Kristen Matsuno
Simulate force around proposed module using hardware CAD to check for issues such as vibrations and toppling
Work with Nate G. to design a cold air delivery option
Nathaniel Liu
Design test fixture to simulate operating environment via emulating thermal resistance
Pick up hardware orders, continue purchasing items as necessary and maintaining purchase records.
Sponsor Feedback and Corresponding Action Items
Sponsor explained that it was permissible to reduce the surface area of the substrate exposed to the heated airflow by insulating around where the inkjet droplet(s) are to be placed.
This relaxed project requirements further without compromising the required performance of the Chill Puck, affording a greater factor of safety.
Sponsor clarified the existing setup even further, pointing out that the test chamber is accessed through a single small hole directly above the mass balance.
Based on this, the CAD mockup will be updated before the first physical Chill Puck manifestation is assembled.
Sponsor approved the idea of injecting cold air into the heated airflow to provide in-flow convective cooling to a low temperature air stream.
This created another physical deliverable for the project while also relaxing the performance needs of the actual Chill Puck module.
Instructor Feedback and Corresponding Action Items
Professor Tustaniwskyj's suggestion to use graphite and/or copper heat tubes/pipes to direct the flow of heat has been taken under very serious consideration.
Both graphite planar heat spreading options and copper heat pipes may be included in the final design depending on where hardware components are finally placed relative to the heated airflow.
Comments from Other Students
Aside from helpful feedback during the Design Proposal Presentation, a student outside the class who currently works at Hi-Z Inc., a thermoelectric generator company in San Diego, is available
to offer feedback and insight on the use of TE cooling, which he sees as a very feasible solution method for this design project.
Risks and Areas of Concern
Electrical current requirements of the Peltier cooler necessitate an Arduino shield of some kind, or, as Steve Roberts suggested, a MOSFET circuit.
Data collection through an Arduino Nano seems unfeasible due to storage requirements, so a wireless communication suite of some kind might actually be a requirement rather than a "wow" solution characteristic.
Resources or Information Required but not Available
Dimensions of hole on underside of heated airflow setup not yet provided (awaiting sponsor).
Flexibility in modification of heated airflow setup not fully discussed, but known to be possible.
Schedule
Monday 4/17 - 10:00 am Team meeting
3:00 pm Meeting with Professor T.
4:00 pm Secondary team meeting (hardware will have been picked up from Amazon UCSD delivery by this time)
Wednesday 4/19 - 2:00 pm Phone call with sponsor contact (Jeremy)
5:00 pm Team meeting
Friday 4/21 - Finish construction of first hardware iteration.
Budget
$35 Spent on Risk Reduction (Winter 2017)
$11.37 Adafruit Trinket
$19.31 Adafruit Thermocouple Amplifier
$8.12 Battery "backpack" add-on
$16.99 Ofeely 3.7V 3000mAh LiPo Battery
$11.99 Halnziye High Performance Thermal Grease
$11.98 Arctic Silver Cooling Adhesive
$8.44 ThermalCoolFlux Thermal Paste
$1076.80 Remaining Budget for Equipment and Parts
Progress on Report and Webpage
Report rough draft completed, impact on society currently under consideration.
Webpage has been updated with reports, Gantt chart has been updated accordingly (no major timeline changes).