Design and Development of a Thermoelectric

Beverage CoolerBy:

Brandon Carpenter Andrew Johnston

Tim TaylorFaculty Advisor:

Dr. Quamrul MazumderUniversity 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 in approximately 5 minutes.

• Required Cooling Rate:q= ρ V c q= (1000kg/m3)( 3.54(10-4)m3)( 4.189kJ/kg∙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 q= (.58)(.00383)(3137) q = 6.99W

• Sleeve: ΔT = 16K kAl = .58W/m•K L = .108m r1= .0327m r2= .0349m

• q = 2πLk q= 2π(.108)(.58) = 95.4W [3]

• Total Cooling = 95.4W + 6.99W = 102.4W

Main Components

• Peltier CoolerModel TEC1-12709Rated 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

• Sleeve6061 AluminumCut to appropriate length2.62” Inner Diameter0.065” Wall Thickness

Main Components

• Machined Base6061 AluminumDesigned to accommodate various cans, as dimensions can differ

Manufacturing / Assembly• Aluminum tubing was cut into appropriate • lengths to make sections

1. Beverage Compartment2. Fan Housing (which was not used)3. Wiring Compartment4. 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 (⁰F) dT/dt (⁰F / min) Ambient Air: 65.5(⁰F)

0 82.2   Starting Voltage: 12.45V2 79.7 1.25 Final Voltage: 9.14V4 77.7 16 75.7 18 73.9 0.910 72.3 0.812 70.5 0.9

  dT/dt min 0.8  dT/dt max 1.25  dT/dt ave 0.975

ResultsData in graph form

Discussion• Refrigerator – constant 0.317 F / min⁰• Cooler - maximum 0.65 F / min ⁰ - average 0.317 F / min⁰• 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