11-08-2012, 11:25 AM
Stirling Cry cooler - Classification
Stirling Classification.ppt (Size: 1.1 MB / Downloads: 64)
Process 1 -2
Compression space is filled with gas (point 1).
There is no gas in expansion space.
Expansion piston is stationary.
Compressor piston moves.
The gas is compressed rejecting heat Qc.
Process 2-3
Both the compressor and expander pistons move.
The gas is transferred from compression space to expansion space through regenerator, getting cooled in the process
Process 3-4
Compressor piston is stationary.
Expander piston moves.
The gas is expanded absorbing heat QE.
Process 4-1
Both the compressor and expander pistons move.
The gas is transferred from compression space to expansion space through regenerator, getting heated in the process.
Comparison
The pressure at any instant of time is same in both the spaces.
The α - machine has the disadvantage of large dead volume. This is the volume which is not swept by any of the pistons.
The β - machine has the disadvantage of heat transfer from hot space to cold space through cylinder walls, thus reducing the refrigerating effect.