Team P15441 Mini Air Sub-System Design Review 04/02/15

Team Introduction Team Member Major Role Daniel Probst Electrical Engineer Project Leader Usama Haq Mechanical Engineer Lead Relations Nathan Serfass Technical Lead Joshua Erbland Electrical Design Lead Alexander Cornell Mechanical Design Lead P15441 04/02/15

Agenda Background Customer and Engineering Requirements Sub-System Overview & Specs Distribution Sub-System Analysis and Specifications Thermal Air Flow Housing Electrical UI Preliminary Mockup Test Plan Risk Assessment Project Schedule Budget Summary P15441 04/02/15

Market State Features Cost Mini Air Cryothermic Scarf Handy Cooler Forced Air Thermoelectric Rechargeable Battery Cooling only Cryothermic Scarf Contact Thermoelectrics Heating and cooling 4 hour battery life Rechargeable battery Handy Cooler Forced Air Water thermal storage Cooling only P15441 04/02/15 Cost

Project Deliverables P15441 03/03/15

Customer Requirements P15441 04/02/15

Engineering Requirements P15441 04/02/15

Constraints Budget of $1000 UL Certifiable Humidity factor for Temperature < 30% Lot sizes of 10,000 Maximum Unit Labor Time of 5 min. Airflow comfortable 4” from device 160° arc at neck P15441 04/02/15

System Architecture P15441 04/02/15

Subsystem Specs Distribution Thermal Air Flow Electrical Weight 55% 35% 10% Cost 45% Power 65% 30% 5% P15441 04/02/15

Thermal Analysis Current Process Using a Matlab code to generate all potential values Working with multiple SME’s to debug and validate solutions Heatsink fin design We believe a significant pressure drop exists at the heat sinks. Further analysis into the effect of the number of fins, surface area, and width between the fins will be conducted in the next phase. Thermal Model Currently verifying with SME’s and trying to validate solution with mock-up designs. P15441 04/02/15

Thermal Sub-System Overview P15441 04/02/15

Air Flow Analysis FIn/Motor Design Identify Fan Pressures Fan Total Pressure Fan Velocity Pressure Fan Static Pressure Design Size Trailing Edge of Blade Hub Radius nozzle design cfms needed at exit how does this relate to fan cfms etc P15441 04/02/15

Housing CAD Drawings Analysis of why design was chosen weights, sizes, etc P15441 04/02/15

Electrical Sub-System Overview P15441 04/02/15

Battery Considerations Rechargeable Battery Type Voltage [V] Energy Density [WHr/Kg] Lead-Acid 2.1 30-40 NiCd 1.2 40-60 NiMH 1.3 80-100 Li-Ion 3.7 130-200 P15441 04/02/15

User Interface Considerations On/Off Power Switch Options - SPDT Pushbutton Rocker Switch Slide Switch P15441 04/02/15

Power Regulation A single Li-on or Li-po battery cell will be used assuming that a boost converter can be designed cheaply enough to achieve the voltage output we need for the thermoelectric module. Advantages to 1 cell: Simpler/cheaper battery charging system. 1 larger battery is cheaper than 2 smaller batteries. Wider range of integrated solutions available. Advantages to 2 cells: Simpler boost converter design. P15441 04/02/15

Preliminary Mockup Parts: 7 cfm, 40 mm fan w/ brushless motor Melcor 5629 TEM 40x40 mm heatsinks Anemometer Readings: Fan: 2.5 m/s (5.6 mph) At Cold Side: 0.24 m/s Thermocouple Readings: Ambient: 71°F Cold Side: 74°F Hot Side: 127°F Housing Fan + Motor Heatsinks Hot Side Thermoelectric Cold Side P15441 04/02/15

Preliminary Mockup Rev. 2 Housing Parts: 7 cfm, 40 mm fan w/ brushless motor Melcor 5629 TEM 40x40 mm heatsinks 10x40 mm nozzle for cold side Anneometer Readings: Fan: 2.5 m/s (5.6 mph) At Cold Side: 0.45 m/s ¼” Deflection of paper Thermocouple Readings: Ambient: 75°F Cold Side: 64°F Hot Side: 108°F Hot Side Thermoelectric & Heatsinks Nozzle Fan + Motor P15441 04/02/15 Cold Side

Preliminary Test Plan Metric Testing Method Weight Measure sub elements with scale Velocity of air at fan Velocity of air at exit port Measure using anemometer Temperature differential at heatsink Temperature differential at exit port Measure using thermocouple at heatsink Unkown method for exit port Battery Life Measure power supplied to motor using multimeter Measure power supplied to TEM Measure power dissipation Comfort Perform survey of individuals with a prototype consisting of similar final weight pass/fail criteria will be based upon engineering requirements P15441 04/02/15

Risks Assessment P15441 04/02/15

Schedule for Phase 4 P15441 04/02/15

Budget Total Budget: $1000 Current Costs: First Round Prototyping: $21.63 Second Round Prototyping: $6.97+ Future Potential Costs: 3D printed housing P15441 04/02/15

Summary Technical Status: Power requirement is high and more R&D needs to be developed to better meet the customer requirements Upcoming steps: Refining the thermodynamic model, get a better understanding of feasibility analysis, create subsystems and verify all results Cost- Current budget is tight and suppliers need to be contacted for specific quotes P15441 04/02/15

Questions and Feedback P15441 04/02/15

References http://www.amazon.com/dp/B007OWTTAO?psc=1 – Cool-on-the-Go http://dhama-innovations.myshopify.com/products/climaware-cryothermic-scarf - Cyrothermic Scarf P15441 04/02/15