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Page 1: Peltier Devices

http://www.penguinslab.com/peltier.htm

David Jones and Michael Wilcox

Page 2: Peltier Devices

Bismuth Telluride cubes carry heat from one direction to the other

Charge comes from DC Voltage

Page 3: Peltier Devices

Increase in Voltage => Increase in ΔTAt 12 V => ΔT = 51˚C

Current heat load = 0WThot,spec chart = 35˚C, Tcool,spec chart = -16˚C

Page 4: Peltier Devices

Two Peltier Devices connected to stainless steel plates

Coolant runs between radiator and peltier devices.

Page 5: Peltier Devices

Coolant is used to keep the Thot down (Troom)Pumped through a fan-cooled radiatorCoolant used for anti-rust, anti-mold, increased

heat dissipation

Stainless Steel used Easily cleanedResistant to RustingHolds Heat WellStainless Steel: k=14.9 W/m*K

Page 6: Peltier Devices

Thermal grease used to bridge the gapStainless Steel @10,000 kN/m2, R=.7-4.0 x10-4 m2*K/WThermal grease (@ 3500kN/m2), R=.04 x10-4

m2*K/W

CopperStainless

Page 7: Peltier Devices

Measure time constant (τ) to reach steady stateCooling

τ = 86s

Return to Troom

τ = 98.8s

Page 8: Peltier Devices

Basic Assumption: 1-D Transient ConductionGoverning Equation: Temperature Distribution:

Additional Assumptions:h = 300 W/(m^2*K)Peltier device neglected, exceptDevice modeled by using

T∞ = Ti - ΔT = -27˚C

Page 9: Peltier Devices

Time constant: τ = 89.9s