scholarly journals The Quantum Otto Heat Engine with a Relativistically Moving Thermal Bath

Author(s):  
Nikolaos Papadatos
Keyword(s):  
Entropy ◽  
2021 ◽  
Vol 23 (3) ◽  
pp. 353
Author(s):  
Jin-Fu Chen ◽  
Ying Li ◽  
Hui Dong

Finite-time isothermal processes are ubiquitous in quantum-heat-engine cycles, yet complicated due to the coexistence of the changing Hamiltonian and the interaction with the thermal bath. Such complexity prevents classical thermodynamic measurements of a performed work. In this paper, the isothermal process is decomposed into piecewise adiabatic and isochoric processes to measure the performed work as the internal energy change in adiabatic processes. The piecewise control scheme allows the direct simulation of the whole process on a universal quantum computer, which provides a new experimental platform to study quantum thermodynamics. We implement the simulation on ibmqx2 to show the 1/τ scaling of the extra work in finite-time isothermal processes.


2019 ◽  
Author(s):  
Riccardo Spezia ◽  
Hichem Dammak

<div> <div> <div> <p>In the present work we have investigated the possibility of using the Quantum Thermal Bath (QTB) method in molecular simulations of unimolecular dissociation processes. Notably, QTB is aimed in introducing quantum nuclear effects with a com- putational time which is basically the same as in newtonian simulations. At this end we have considered the model fragmentation of CH4 for which an analytical function is present in the literature. Moreover, based on the same model a microcanonical algorithm which monitor zero-point energy of products, and eventually modifies tra- jectories, was recently proposed. We have thus compared classical and quantum rate constant with these different models. QTB seems to correctly reproduce some quantum features, in particular the difference between classical and quantum activation energies, making it a promising method to study unimolecular fragmentation of much complex systems with molecular simulations. The role of QTB thermostat on rotational degrees of freedom is also analyzed and discussed. </p> </div> </div> </div>


2020 ◽  
pp. 56-58
Author(s):  
P.V. Gubarev ◽  
D.V. Glazunov ◽  
V.G. Ruban ◽  
A.S. Shapshal

The thermal calculation of the locomotive traction engine collector is proposed. The equations of the heat balance of its elements are obtained taking into account the cooling air. The calculation results and experimental data of thermal imaging control are presented. Keywords: traction electric motor, collector, thermal calculation, thermal imaging control. [email protected]


Author(s):  
Jochen Rau

Thermodynamic processes involve energy exchanges in the forms of work, heat, or particles. Such exchanges might be reversible or irreversible, and they might be controlled by barriers or reservoirs. A cyclic process takes a system through several states and eventually back to its initial state; it may convert heat into work (engine) or vice versa (heat pump). This chapter defines work and heat mathematically and investigates their respective properties, in particular their impact on entropy. It discusses the roles of barriers and reservoirs and introduces cyclic processes. Basic constraints imposed by the laws of thermodynamics are considered, in particular on the efficiency of a heat engine. The chapter also introduces the thermodynamic potentials: free energy, enthalpy, free enthalpy, and grand potential. These are used to describe energy exchanges and equilibrium in the presence of reservoirs. Finally, this chapter considers thermodynamic coefficients which characterize the response of a system to heating, compression, and other external actions.


Author(s):  
J.V. Lasecki ◽  
R.F. Novak ◽  
J.R. McBride ◽  
J.T. Brockway ◽  
T.K. Hunt
Keyword(s):  

Sign in / Sign up

Export Citation Format

Share Document