Journal of Technology & Science
November 28, 2010
STATISTICAL MECHANICS;
Research from K. Hovhannisyan and co-researchers provides new data on
statistical mechanics
According to recent research published in the Journal of Statistical
Mechanics - Theory and Experiment, "Situations where a spontaneous
process of energy or matter transfer is enhanced by an external device
are widespread in nature (the human sweating system, enzyme catalysis,
facilitated diffusion across biomembranes, industrial heat-exchangers
and so on). The thermodynamics of such processes remains, however,
open."
"Here we study enhanced heat transfer by using a model junction
immersed between two thermal baths at different temperatures T-h and
T-c (T-h > T-c). The transferred heat power is enhanced via
controlling the junction by means of external time-dependent fields.
Provided that the spontaneous heat flow process is optimized over the
junction Hamiltonian, any enhancement of this spontaneous process
demands consumption and subsequent dissipation of work. The efficiency
of the enhancement is defined via the increment in the heat power
divided by the amount of work done. We show that this efficiency is
bounded from above by T-c/(T-h-T-c). Formally this is identical to the
Carnot bound for the efficiency of ordinary refrigerators which
transfer heat from cold to hot bodies," wrote K. Hovhannisyan and
colleagues.
The researchers concluded: "It also shares some (but not all) physical
features of the Carnot bound."
Hovhannisyan and colleagues published their study in the Journal of
Statistical Mechanics - Theory and Experiment (The thermodynamics of
enhanced heat transfer: a model study. Journal of Statistical
Mechanics - Theory and Experiment, 2010;():6010).
For additional information, contact K. Hovhannisyan, Yerevan Physics
Institute, Alikhanian Bros St. 2, Yerevan 375036, Armenia.
The publisher's contact information for the Journal of Statistical
Mechanics - Theory and Experiment is: IOP Publishing Ltd., Dirac
House, Temple Back, Bristol BS1 6BE, England.
From: A. Papazian
November 28, 2010
STATISTICAL MECHANICS;
Research from K. Hovhannisyan and co-researchers provides new data on
statistical mechanics
According to recent research published in the Journal of Statistical
Mechanics - Theory and Experiment, "Situations where a spontaneous
process of energy or matter transfer is enhanced by an external device
are widespread in nature (the human sweating system, enzyme catalysis,
facilitated diffusion across biomembranes, industrial heat-exchangers
and so on). The thermodynamics of such processes remains, however,
open."
"Here we study enhanced heat transfer by using a model junction
immersed between two thermal baths at different temperatures T-h and
T-c (T-h > T-c). The transferred heat power is enhanced via
controlling the junction by means of external time-dependent fields.
Provided that the spontaneous heat flow process is optimized over the
junction Hamiltonian, any enhancement of this spontaneous process
demands consumption and subsequent dissipation of work. The efficiency
of the enhancement is defined via the increment in the heat power
divided by the amount of work done. We show that this efficiency is
bounded from above by T-c/(T-h-T-c). Formally this is identical to the
Carnot bound for the efficiency of ordinary refrigerators which
transfer heat from cold to hot bodies," wrote K. Hovhannisyan and
colleagues.
The researchers concluded: "It also shares some (but not all) physical
features of the Carnot bound."
Hovhannisyan and colleagues published their study in the Journal of
Statistical Mechanics - Theory and Experiment (The thermodynamics of
enhanced heat transfer: a model study. Journal of Statistical
Mechanics - Theory and Experiment, 2010;():6010).
For additional information, contact K. Hovhannisyan, Yerevan Physics
Institute, Alikhanian Bros St. 2, Yerevan 375036, Armenia.
The publisher's contact information for the Journal of Statistical
Mechanics - Theory and Experiment is: IOP Publishing Ltd., Dirac
House, Temple Back, Bristol BS1 6BE, England.
From: A. Papazian