TY - JOUR
T1 - Ecological efficiency of finite-time thermodynamics
T2 - A molecular dynamics study
AU - Rojas-Gamboa, David A.
AU - Rodríguez, Juan I.
AU - Gonzalez-Ayala, Julian
AU - Angulo-Brown, F.
N1 - Publisher Copyright:
© 2018 American Physical Society.
PY - 2018/8/27
Y1 - 2018/8/27
N2 - We present a molecular dynamics simulation of a two-dimensional Carnot engine. The optimization of this engine is achieved through the velocity of the piston, allowing not only the optimization of power output but also some other figures of merit involving entropy production. The maximum power and maximum ecological efficiencies are computed. It is shown that the near ideal gas working substance displays an endoreversible Carnot-like engine behavior. This can be considered as a prove of the validity of the Carnot-like endoreversible model. An effective reversible cycle different than the Carnot one is obtained, in agreement with the endoreversible hypothesis flexibility. We compare the efficiencies stemming from an ideal gas approximation with those of the simulation, and then we propose a suitable approximation to an endoreversible heat engine and to a reversible Joule-Brayton cycle which fits very well to the simulation results. Finally, we show that the maximum ecological efficiency η=1-τ3/4, which is also very close to the upper bound of the low-dissipation heat engine under maximum ecological (and Omega) conditions, is close for describing the dynamics of the simulated cycle under maximum power and maximum ecological conditions in the so-named heat engine operability region.
AB - We present a molecular dynamics simulation of a two-dimensional Carnot engine. The optimization of this engine is achieved through the velocity of the piston, allowing not only the optimization of power output but also some other figures of merit involving entropy production. The maximum power and maximum ecological efficiencies are computed. It is shown that the near ideal gas working substance displays an endoreversible Carnot-like engine behavior. This can be considered as a prove of the validity of the Carnot-like endoreversible model. An effective reversible cycle different than the Carnot one is obtained, in agreement with the endoreversible hypothesis flexibility. We compare the efficiencies stemming from an ideal gas approximation with those of the simulation, and then we propose a suitable approximation to an endoreversible heat engine and to a reversible Joule-Brayton cycle which fits very well to the simulation results. Finally, we show that the maximum ecological efficiency η=1-τ3/4, which is also very close to the upper bound of the low-dissipation heat engine under maximum ecological (and Omega) conditions, is close for describing the dynamics of the simulated cycle under maximum power and maximum ecological conditions in the so-named heat engine operability region.
UR - http://www.scopus.com/inward/record.url?scp=85052737856&partnerID=8YFLogxK
U2 - 10.1103/PhysRevE.98.022130
DO - 10.1103/PhysRevE.98.022130
M3 - Artículo
C2 - 30253568
SN - 2470-0045
VL - 98
JO - Physical Review E - Statistical, Nonlinear, and Soft Matter Physics
JF - Physical Review E - Statistical, Nonlinear, and Soft Matter Physics
IS - 2
M1 - 022130
ER -