1. Design of a Rapid Beverage Chiller for iced tea enthusiasts

2. Unaided, iced tea takes hours to make Brew: 2-8 minutesCool: 2-6 hours

3. Market for specialized kitchen tools

4. Brew directly into ice Functionality: Fill pitcher with ice Brews tea Pours tea into pitcher Issues: Hot tea melts ice Ice dilutes tea “That freezer taste”

5. Ice water circulation Functionality: Add ice and water Insert can or bottle Rotates container, sprays with ice water Issues: Requires ice (minor) Bad for tea (fixable?)

6. Cool new technology: TEC’s Pros: Super compact, light No moving parts Cons: Inefficient (40-70%) (≈300% for full-size fridge)

7. Ice versus price Isolated-ice systems Pros: More inexpensive Likely more compact Cons: Needs lots of ice for hot tea Proposal: TEC-cooled system Pros: Plug and play Precise temperatures Cons: Pricier Bulky (heatsinks!) Draws a lot of power Gives off a lot of heat

8. Rapid Beverage Cooler: Take 1 Vessel + sensor Heatsink Fan Stirrer Spigot TEC

9. Design 1: Too hot for TEC operation! Problem: Can’t operate past ≈80°C Not needed at high temps Solution: Only run TEC below certain temperature

10. Rapid Beverage Cooler: Take 2 Three-state process: 1.Upper fans on, TEC off: Cool to ≈60°C 2.All fans on, TEC on: Cool to room temp. 3.Lower fans on, TEC on: Cool to final temp.

11. Circuit breaker limits performance Power from wall: 1500 W (US/Canada) Power through TEC(s): 1200 W Breaker is limiting factor (67% efficient TEC): 0.67 × 1500 W × 0.8 = 800 W Calculate the temperature profile: Aggressive air cooling Constant TEC heat flow: 800W (simplistic) TEC turns on at 60°C

12. Cool a liter of tea in 9 minutes Time elapsed (minutes) Temperature (°C)

13. Problems I may encounter… Variation in TEC heat transfer rate – Stage 2: Better than estimated – Stage 3: Worse than estimated Heat dissipation too slow → Slower cooling process. Too expensive to mass-produce (>$250?) Backup plan: Investigate other cooling systems

15. Demand for iced tea chillers TECs enable powerful, convenient chillers 1 liter: 90°C to 6°C in 9 minutes