presented by:
Trevor Bourgeois
Mike Horne
Peter Smith
Erin MacNeil

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ThermoAcoustic Refrigeration
Design Description
 Thermoacoustic Refrigerator
– Unpressurized System
– Air as Gas Medium
– Loudspeaker as Acoustic Driver
– Variable design (stacks)
 Advantages of Thermoacoustic Refrigeration
– No Environmentally-Harmful Refrigerants
– Mechanically Simple
Summary of Fall Term
 Work to understand Theory
 Development of Mathematical Model
 Construction of two Prototypes
– Standing wave created
– No DT
 Identification of Stack as most important component
Main Prototype Components
 Speaker
 Gas
 Tube
 Stack
 Heat Exchangers
Speaker
 Considerations
– Power Capacity
– Frequency Response
 Choice
– 10 inch
– Operates At Low Frequencies (100 Hz)
– 400 W Maximum Power
Gas Medium
 Considerations
– Physical Properties
– Sealing
– Cost
 Choice
– Air
– Atmospheric Pressure
Tube
 Considerations
– Length
– Diameter
– Sound Reflection
– Low Acoustic Losses
– Sound Transmission
 Choice
– 1.5” PVC Tube
– Flat End
Stack
 Considerations
– Gap Size
– Material properties
– Material thickness
– Location
– Length
– Does not impede wave
 Choice
– Paper
– Aluminum Screen
Heat Exchangers
 Considerations
– Material
– Type
 Choice
– Aluminum
– Water Circulated
 Solid Porous Material
 Give And Takes Heat From Gas
 Heat Transfer
 DT Across
Design Considerations
 Gap Size
 Solid Thickness
 Position
 Length
 Ability Of Sound To Pass Through
 Physical Properties
Stack Designs
 Foil
 Paper
 Foam
 Lexan
 Screen