Irreversible Work and Inner Friction in Quantum Thermodynamic Processes

Differential geometry offers a powerful framework for optimising and characterising finite-time thermodynamic processes, both classical and quantum. Here, we start by a pedagogical introduction to the notion of thermodynamic length. We review and connect different frameworks where it emerges in the quantum regime: adiabatically driven closed systems, time-dependent Lindblad master equations, and discrete processes. A geometric lower bound on entropy production in finite-time is then presented, which represents a quantum generalisation of the original classical bound. Following this, we review and develop some general principles for the optimisation of thermodynamic processes in the linear-response regime. These include constant speed of control variation according to the thermodynamic metric, absence of quantum coherence, and optimality of small cycles around the point of maximal ratio between heat capacity and relaxation time for Carnot engines.

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Quantum Relativistic Diesel Engine with Single Massless Fermion in 1 Dimensional Box System

Jurnal Penelitian Fisika dan Aplikasinya (JPFA) ◽

10.26740/jpfa.v8n1.p25-32 ◽

2018 ◽

Vol 8 (1) ◽

pp. 25 ◽

Cited By ~ 4

Author(s):

Deny Pra Setyo ◽

Eny Latifah ◽

Arif Hidayat ◽

Hari Wisodo

Keyword(s):

Heat Capacity ◽

Diesel Engine ◽

Quantum Systems ◽

Analogue Model ◽

Massless Fermion ◽

Engine Efficiency ◽

Capacity Ratio ◽

Classical Analogue ◽

Quantum Thermodynamic ◽

Thermodynamic Processes

The quantum Diesel of a single fermion in 1D box system has been explored. The Fermion particle meets the Dirac's relativistic Hamiltonian with a chosen mass worth zero. This Relativistic Diesel engine research aims to obtain Diesel engine efficiency that utilizes massless fermion particles as a working substance. This study implements a modified analogy model of the classical analogue model to quantum with the implementation of the first law of thermodynamics for quantum systems so that quantum thermodynamic processes can be defined explicitly. The exploratory results of a single quantum fermion Diesel engine of a single massless system are efficiency formulation that is suitable for the efficiency of a classic Diesel engine, but its heat capacity ratio is unique, that is 2. Based on the value of heat capacity ratio, the efficiency is higher than the classical.

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Quantum Thermodynamic Processes

Quantum Thermodynamics - Lecture Notes in Physics ◽

10.1007/978-3-540-70510-9_25 ◽

2009 ◽

pp. 291-313 ◽

Cited By ~ 103

Author(s):

Jochen Gemmer ◽

M. Michel ◽

G. Mahler

Keyword(s):

Quantum Thermodynamic ◽

Thermodynamic Processes

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Analysis of the Thermodynamic Processes of Internal Combustion Engines Operating on Biodiesel

National Interagency Scientific and Technical Collection of Works. Design, Production and Exploitation of Agricultural Machines ◽

10.32515/2414-3820.2018.48.3-11 ◽

2018 ◽

pp. 3-11

Author(s):

Igor Bershliage ◽

◽

Leonid Malai ◽

Keyword(s):

Internal Combustion Engines ◽

Internal Combustion ◽

Combustion Engines ◽

Thermodynamic Processes

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Processes and Responses

10.1093/oso/9780199595068.003.0007 ◽

2017 ◽

Author(s):

Jochen Rau

Keyword(s):

Heat Engine ◽

Cyclic Process ◽

Free Enthalpy ◽

Initial State ◽

Thermodynamic Potentials ◽

Grand Potential ◽

Laws Of Thermodynamics ◽

Cyclic Processes ◽

Energy Exchanges ◽

Thermodynamic Processes

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.

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Defining the Thermodynamic Efficiency in a Wave Rotor

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4033508 ◽

2016 ◽

Vol 138 (11) ◽

Cited By ~ 4

Author(s):

Shining Chan ◽

Huoxing Liu ◽

Fei Xing

Keyword(s):

Gas Turbine ◽

Control Volume ◽

Thermodynamic Efficiency ◽

Wave Rotor ◽

Wave Rotors ◽

Compression And Expansion ◽

Efficiency Estimation ◽

Parametric Analyses ◽

Control Volumes ◽

Thermodynamic Processes

A wave rotor enhances the performance of a gas turbine with its internal compression and expansion, yet the thermodynamic efficiency estimation has been troubling because the efficiency definition is unclear. This paper put forward three new thermodynamic efficiency definitions to overcome the trouble: the adiabatic efficiency, the weighted-pressure mixed efficiency, and the pressure pre-equilibrated efficiency. They were all derived from multistream control volumes. As a consequence, they could correct the efficiency values and make the values for compression and expansion independent. Moreover, the latter two incorporated new models of pre-equilibration inside a control volume, and modified the hypothetical “ideal” thermodynamic processes. Parametric analyses based on practical wave rotor data demonstrated that the trends of those efficiency values reflected the energy losses in wave rotors. Essentially, different thermodynamic efficiency definitions indicated different ideal thermal cycle that an optimal wave rotor can provide for a gas turbine, and they were recommended to application based on that essence.

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