Design and Development of a Thermoelectric Beverage Cooler

advertisement
Design and Development of a
Thermoelectric
Beverage Cooler
By:
Brandon Carpenter
Andrew Johnston
Tim Taylor
Faculty Advisor:
Dr. Quamrul Mazumder
University of Michigan - Flint
Objective
• Refrigerator designed for cooling large
multiple items
• Inefficient if only a single item is to
be cooled
• Due to size is non-portable
• Technology requires coolant, compressor,
and cumbersome tubing
Objective
• Apply concept of refrigerator to a small
scale device
• Solid-state, eliminate need for coolants
• Portability; can be taken wherever needed
• Concentrate cooling onto single object to
be cooled, eliminate energy waste in
cooling empty space
Objective
Turn This
Into This
Engineering Approach
• Use Peltier thermo cooler to provide
cooling
• Use tight fitting aluminum sleeve to
enhance conductivity
• Machine base to match contour of
can bottom
• Use fans with heat sink to remove heat
• Power with drill battery
Preliminary Calculations
• Initial goal: to cool a can from 700F to 350F
approximately 5 minutes.
• Required Cooling Rate:
q= ρ V c
š‘‘š‘‡
š‘‘š‘”
q= (1000kg/m3)( 3.54(10-4)m3)( 4.189kJ/kgāˆ™K)( .0533 K/second)
This gives a value for q of .079 kW, or 79 Watts.
Further Calculations
• Base: ΔT = 16K kAl = .58W/m•K A= .00383m2 dx= .0051m
• q = kA
š‘‘š‘‡
š‘‘š‘„
q= (.58)(.00383)(3137) q = 6.99W
• Sleeve: ΔT = 16K kAl = .58W/m•K
L = .108m r1= .0327m r2= .0349m
• q = 2πLk
š›„š‘‡
ln š‘Ÿ2
q= 2π(.108)(.58)
š‘Ÿ1
16
.0349
š‘™š‘›.0327
= 95.4W [3]
• Total Cooling = 95.4W + 6.99W = 102.4W
Main Components
• Peltier Cooler
Model TEC1-12709
Rated for 90W/ 139W Max
Notes on Cooler
• While a cooler with a higher rated wattage
would theoretically be able to remove
more heat, it creates more heat due to
resistance and requires a much larger
heat sink.
• In order to remain portable a smaller
cooler was needed, affecting cooling time.
Main Components
• Sleeve
6061 Aluminum
Cut to appropriate length
2.62” Inner Diameter
0.065” Wall
Thickness
Main Components
• Machined Base
6061 Aluminum
Designed to accommodate various cans,
as dimensions can differ
Manufacturing / Assembly
• Aluminum tubing was cut into appropriate
• lengths to make sections
1.
2.
3.
4.
Beverage Compartment
Fan Housing (which was not used)
Wiring Compartment
Battery Compartment
Manufacturing / Assembly
• Discs were made
to serve as plates
between sections
and for mounting
purposes
Manufacturing / Assembly
• Components were
assembled using
machine screws and
adhesives
Manufacturing / Assembly
• Insulation was placed
around beverage
compartment
• Thermal paste was
applied between
thermo cooler,
heat sink, top disc,
base, and sleeve
Testing Procedure
Testing Procedure
• A 12 oz. pop can is filled with water and placed in
the beverage compartment
• Initial temperature of the water is recorded
• Cooler is turned on, and temperature is recorded
in two minute intervals
• Additionally, the ambient air temperature, starting
battery voltage, and final battery voltage are
recorded to check for any correlation
Testing Procedure
• For each test, the data is entered into
an Excel spreadsheet
For comparison purposes, a
similar test was conducted
using a refrigerator
Cooling Module Test #1
Time (minutes) Temperature (ā°F) dT/dt (ā°F / min)
0
82.2
2
79.7
1.25
4
77.7
1
6
75.7
1
8
73.9
0.9
10
72.3
0.8
12
70.5
0.9
dT/dt min
0.8
dT/dt max
1.25
dT/dt ave
0.975
Ambient Air: 65.5(ā°F)
Starting Voltage: 12.45V
Final Voltage: 9.14V
Results
Data in graph form
Discussion
• Refrigerator – constant 0.317ā°F / min
• Cooler - maximum 0.65ā°F / min
- average 0.317ā°F / min
š‘‘š‘‡
š‘‘š‘”
• In terms of the cooler outperformed the
refrigerator
• Could only maintain this cooling level for
short period due to battery
Conclusion
• With available technology idea is not
yet practical
• Current Peltier coolers are not very
efficient, require large heat sinks which
hinder portability
• Also battery power/size ratio insufficient
for portability
Download