Main Question or Discussion Point
I'm sure most of you have heard of the Einstein Referigeration Cycle .CONCLUSIONS
The Einstein cycle is a three temperature thermal heat
pump with no work input or output. It receives high temperature
driving heat which is used to pump heat from a low
refrigeration temperature to an ambient rejection temperature.
The refrigeration application analyzed in this study uses
butane-ammonia-water working fluids with the driving heat
input temperature varying from 325 K to 375 K. The entropic
average temperature for this driving heat input is 342 K. This
is a relatively low driving heat source temperature. The
refrigeration temperature from which heat is pumped was
selected to be 266 K and the single heat rejection temperature
was selected to be 315 K. The COP of this cycle is low relative
to two-pressure absorption cycles, which require a liquid
solution pump. A second law analysis gives insight into the
fundamental reasons for the low COP.
The reversible COP was found to be at 0.57. This means
that even if the cycle could be made reversible, it still could not
reach the COP of advanced two-pressure absorption cycles.
This is due primarily to the low generator heat input entropic
average temperature of 342 K.
This reversible COP is degraded by three primary
irreversibilities: 1) the generator internal regenerative heat
exchanger, 2) the evaporator mixing, and 3) the absorber
mixing. They degrade the reversible COP by 0.17, 0.12, and
0.11 respectively, down to 0.17.
The cycle demonstrates a creative approach to achieving
refrigeration with no work requirement, though at a relative
low COP. The second law analysis shows the source of this
low performance to be primarily due to a low generator
temperature. This should be investigated to determine how the
cycle and working fluids might be changed to raise the
generator heat input temperature and various achieve
These developments could make the cycle competitive
with current commercial technology in various applications
such as residential heat pump space cooling and heating. The
cycle can achieve first law heating efficiencies over 100
percent, and reduce summer peak air conditioning loads on
electrical power plants. Other applications are possible where
low cost and reliability are important, such as remote
installations and developing countries without an electrical
infrastructure. Silent operation is also a benefit.
For those who have not i've listed the references for further reading..
ok 342 K is about 156 F ,for anyone with an attic , it seems to me that this is the perfect solution to keeping all of us cool in the summer..
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Delano, A., 1998, “Design Analysis of the Einstein
Refrigeration Cycle,” Ph.D. Thesis, Georgia Institute of
Technology, Atlanta, Georgia.
Einstein, A., and Szilard, L., 1930, “Refrigeration” (Appl:
16 Dec. 1927; Priority: Germany, 16 Dec. 1926) Pat. No.
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Patel, N.C., 1980, “The Calculation of Thermodynamic
Properties and Phase Equilibria Using a New Cubic Equation
of State,” Ph.D. Thesis, Loughborough University of
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