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entropy production by dissipation effects and characteristic vortex evolution in a rocket turbopump

Journal of Hydrodynamics 2023年第5期35卷 993-1007页

作者： De-you Li Jia-qi Zhu Rui-yi Zhang Yi Zhang Zhi-peng Li Hong-jie Wang Zhi-peng Ren School of Energy Science and Engineering Harbin Institute of TechnologyHarbin150001China School of Astronautics Harbin Institute of TechnologyHarbin150001China

The relationship between entropy production and vortex evolution affects the efficiency and stability of rotating machinery.This study investigated the energy characteristics of a rocket turbopump and revealed the correlated mechanisms of the entropy production rate using the dissipation effects and characteristic vortex evolution.For the first time,direct and turbulent dissipation and rigid and shear vorticity decomposition methods were utilized to analyze the correlation between flow loss and characteristic vorticities in rotating machinery.With an increase in the flow rate,the hydraulic losses of the dissipation effects and wall decreased by 60%and 38.3%,respectively,and the proportions of the input energy decreased(from 13%to 8%)and remained stable(8%),respectively.The local direct dissipative entropy production(DDEP)in the inducer-impeller is strongly related to shear entropy,and the correlated effect of total enstrophy on DDEP is weaker than that of shear vorticity,indicating that rigid enstrophy suppresses direct dissipation.The correlation between turbulent dissipation and rigid enstrophy was significantly weaker in the static flow passage of the turbopump owing to the weak rigid rotational effect.The correlation between the rigid entropy and local turbulent dissipative entropy production(TDEP)gradually increased with increasing flow rate,reaching a medium correlation(the maximal correlated degree in the turbopump)and exhibiting rigid rotation effects on the hydraulic loss.Moreover,the flow rate significantly affected the correlation(except for the diffuser),and the two characteristic vorticities reached a maximum at the designed flow rate owing to optimal efficiency and minimum hydraulic loss.

关键词： Rocket turbopump hydraulic loss dissipation entropy production vorticity decomposition Liutex

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Economic and entropy production evaluation of extractive distillation and solvent-assisted pressure-swing distillation by multi-objective optimization

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Chinese Journal of Chemical Engineering 2023年第11期63卷 246-259页

作者： Yao Wang Qing Ye Jinlong Li Qingqing Rui Azhi Yu Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology School of Petrochemical EngineeringChangzhou UniversityChangzhou 213164China

Extractive distillation(ED)and solvent-assisted pressure-swing distillation(SA-PSD)are both special distillation processes that perform good at separating pressure-insensitive azeotropes.However,few reported studies have compared the performance of the two processes.In this paper,ED processes with N-methylpyrrolidone(NMP)and dimethlac-etamide(DMCA)as entrainer,SA-PSD process with isopropyl-alcohol(IPA)as solvent and SA-PSD process with partial heat integration(PHI-PSD)are proposed to achieve high purity separation of a mixture of cyclohexane/2-butanol system.The optimal operating conditions of the processes are obtained after optimizing with NSGA-Ⅱ algorithm when total annual cost(TAC)and the entropy production of process are set as objectives.The optimal results show that the optimal PHI-PSD process has lower TAC by 28.7% and the lower entropy production by 39.5% than the optimal SA-PSD process while the ED process with NMP as entrainer has lower TAC by 50.9% and the lower entropy production by 56.1% than the optimal SA-PSD process.The optimal results show that the ED process with NMP as entrainer has the best economic and thermodynamic efficiency among the four proposed processes in this paper.

关键词： Extractive distillation Solvent-assisted pressure-swing distillation entropy production NSGA-Ⅱalgorithm Computer simulation

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entropy production and Fractal Dimensions in Heavy Ion Nuclear Reaction at Intermediate Energies

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Journal of Applied Mathematics and Physics 2022年第8期10卷 2527-2537页

作者： Wenxia Wang Yiyan Zhao Yongzhong Xing Institute for The Fundamental Physics Tianshui Normal University Tianshui China School of Nuclear Science and Technology Lanzhou University Lanzhou China

The characteristics of the nonlinear dynamics in the Heavy Ion Collision (HIC) at intermediate energies have been studied by evaluating the productions of the Generalized entropy (GE) and the Multifragmentation entropy (ME) as well as the features of the information and fractal dimensions within the Isospin Quantum Molecular Dynamical Model compensated by the lattice methods. Results demonstrate from various views that the existence of deterministic chaos in the dynamical process of reaction.

关键词： entropy production Fractal Dimensions Chaotic Behavior Heavy Ion Nuclear Collision Intermediate Energy

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Fluctuation theorem for entropy production in a chemical reaction channel

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Science China Chemistry 2010年第2期53卷 396-401页

作者： XIAO TieJun HOU ZhongHuai Hefei National Laboratory for Physical Sciences at the Microscale Department of Chemical PhysicsUniversity of Science and Technology of ChinaHefei 230026China

Fluctuation theorem for entropy production in a mesoscopic chemical reaction network is discussed. When the system size is sufficiently large, it is found that, by defining a kind of coarse-grained dissipation function, the entropy production in a reversible reaction channel can be approximately described by a type of detailed fluctuation theorem. Such a fluctuation relation has been successfully tested by direct simulations in a linear reaction model consisting of two reversible channels and in an oscillatory model wherein only one channel is reversible.

关键词： nonequilibrium thermodynamics chemical reaction network entropy production fluctuation theorem

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entropy equilibrium equation and dynamic entropy production in environment liquid

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Progress in Natural Science:Materials International 2002年第3期12卷 22-26页

作者： HU Yinqiao(Cold and Arid Regions Environment and Engineering Institute, Chinese Academy of Sciences, Lanzhou 730000, China) Chinese Acad Sci Cold & Arid Reg Environm & Engn Inst Lanzhou 730000 Peoples R China

The entropy equilibrium equation is the basis of the nonequilibrium state thermodynamics. But the internal energy implies the kinetic energy of the fluid micelle relative to mass center in the classical entropy equilibrium equation at present. This internal energy is not the mean kinetic energy of molecular movement in thermodynamics. Here a modified entropy equilibrium equation is deduced, based on the concept that the internal energy is just the mean kinetic energy of the molecular movement. A dynamic entropy production is introduced into the entropy equilibrium equation to describe the dynamic process distinctly. This modified entropy equilibrium equation can describe not only the entropy variation of the irreversible processes but also the reversible processes in a thermodynamic system. It is more reasonable and suitable for wider applications.

关键词： nonequilibrium thermodynamics entropy equilibrium equation entropy production irreversible processes environ- ment liquid.

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Time dependence of entropy flux and entropy production for a dynamical system driven by noises with coloured cross-correlation

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Chinese Physics B 2007年第1期16卷 42-46页

作者：谢文贤徐伟蔡力 Department of Applied Mathematics Northwestern Polytechnical University Xi'an 710072 China College of Astronautics Northwestern Polytechnical University Xi' an 710072 China

This paper shows the Fokker-Planck equation of a dynamical system driven by coloured cross-correlated white noises in the absence and presence of a small external force. Based on the Fokker-Planck equation and the definition of Shannon＇s information entropy, the time dependence of entropy flux and entropy production can be calculated. The present results can be used to explain the extremal behaviour of time dependence of entropy flux and entropy production in view of the dissipative parameter γ of the system, coloured cross-correlation time τ and coloured cross-correlation strength λ.

关键词： information entropy entropy flux entropy production coloured cross-correlation,Fokker-Planck equation

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Energetic and Entropic Changes in Volume Work and Chemical Reactions

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Advances in Chemical Engineering and Science 2024年第1期14卷 8-47页

作者： Frank Diederichs Independent Researcher Schwarmstedt Germany

In the present study, energetic and entropic changes are investigated on a comparative basis, as they occur in the volume changes of an ideal gas in the Carnot cycle and in the course of the chemical reaction in a lead-acid battery. Differences between reversible and irreversible processes have been worked out, in particular between reversibly exchanged entropy (∆eS) and irreversibly produced entropy (∆iS). In the partially irreversible case, ∆eS and ∆iS add up to the sum ∆S for the volume changes of a gas, and only this function has an exact differential. In a chemical reaction, however, ∆eS is independent on reversibility. It arises from the different intramolecular energy contents between products and reactants. entropy production in a partially irreversible Carnot cycle is brought about through work-free expansions, whereas in the irreversible battery reaction entropy is produced via activated complexes, whereby a certain, variable fraction of the available chemical energy becomes transformed into electrical energy and the remaining fraction dissipated into heat. The irreversible reaction process via activated complexes has been explained phenomenologically. For a sufficiently high power output of coupled reactions, it is essential that the input energy is not completely reversibly transformed, but rather partially dissipated, because this can increase the process velocity and consequently its power output. A reduction of the counter potential is necessary for this purpose. This is not only important for man-made machines, but also for the viability of cells.

关键词： Exchanged entropy entropy production Coupled Reactions Activated Complexes Power Output

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Fluctuation theorem for entropy production at strong coupling

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Chinese Physics B 2020年第1期29卷 175-180页

作者：徐酉阳刘娟冯芒 Faculty of Science Kunming University of Science and TechnologyKunming 650500China Faculty of Mechanical and Electrical Engineering Kunming University of Science and TechnologyKunming 650500China State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071China School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China

Fluctuation theorems have been applied successfully to any system away from thermal equilibrium,which are helpful for understanding the thermodynamic state evolution.We investigate fluctuation theorems for strong coupling between a system and its reservoir,by path-dependent definition of work and heat satisfying the first law of thermodynamics.We present the fluctuation theorems for two kinds of entropy productions.One is the informational entropy production,which is always non-negative and can be employed in either strong or weak coupling systems.The other is the thermodynamic entropy production,which differs from the informational entropy production at strong coupling by the effects regarding the reservoir.We find that,it is the negative work on the reservoir,rather than the nonequilibrium of the thermal reservoir,which invalidates the thermodynamic entropy production at strong coupling.Our results indicate that the effects from the reservoir are essential to understanding thermodynamic processes at strong coupling.

关键词： fluctuation theorem entropy production strong coupling

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Competing Cosmology Models. Can entropy production Help Falsify Cyclic Models of Cosmology, or Variants along the Lines Discussed by Roger Penrose at the ICG Conference in Penn State, 2007?

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Journal of High Energy Physics, Gravitation and Cosmology 2016年第4期2卷 486-505页

作者： Andrew Walcott Beckwith Physics Department College of Physics Chongqing University Huxi Campus Chongqing China

In the inaugural ICG meeting, on August 11, 2007 at Penn State, Roger Penrose [1] gave a presentation about an alternative to cyclic cosmological models, which needs experimental tests for falsifiability. As discussed by Beckwith, in EJTP [2], Penrose brought up how wave equation, as simplified in flat space could lead to a rising vacuum nucleation field which would engender the pop up behavior as sought in most emergent field models of gravity. The scalar field pop up with certain qualifications is not so startling in itself. Now for the radical extension Penrose brought to bear. Penrose asserted in his ICG lecture that there was a good chance that there was no collapse in future events, but that matter would be eventually sucked up by “millions” of black holes, creating a clean-up of most interstellar matter. The issue to be brought up is how to come up with a mapping for re-combination of the black hole collected material, for a big bang, a topic which was not solved by Penrose.

关键词： entropy production Cosmology Variants

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A low-resistance elbow with a bionic sawtooth guide vane in ventilation and air conditioning systems

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Building Simulation 2022年第1期15卷 117-128页

作者： Chi Zhang Angui Li Jigang Che Yue Li Qi Liu Yuhang Zhao School of Building Services Science and Engineering Xi'an University of Architecture and Technology(XAUAT)Xi'an 710055China The Artificial Environment Control Technology Achievement Innovation Center of XAUAT and Yantai Yantai 264006China

Elbow resistance is an important part of energy consumption in ventilation and air conditioning(VAC)systems.By considering the structural characteristics of bat wings and humpback whale pectoral fins,a simplified leading edge for sawtooth guide vanes is designed.Based on the theory of fluid mechanics,the resistance reduction mechanism of the sawtooth guide vane is analyzed.The numerical calculation results show that proper sawtooth groove parameters for the guide vane can effectively reduce the elbow resistance.Compared with that for a normal guide vane,the maximum resistance can be reduced by approximately 9%with the new design.In addition,we analyze the influence of the sawtooth guide vane on the entropy production of the duct elbow and the relationship between entropy production and the resistance of the duct elbow.Finally,the resistance reduction performance of the sawtooth guide vane is verified through full-scale tests.

关键词： bionic sawtooth grooves guide vane resistance entropy production

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