Journal of Non-Equilibrium Thermodynamics最新文献_第8页

A simplified analysis of the Feynman pallet and ratchet mechanism considering different forms of generated power 考虑不同发电形式的费曼托盘和棘轮机构的简化分析

IF 6.6 3区工程技术

Journal of Non-Equilibrium Thermodynamics Pub Date : 2023-01-18 DOI: 10.1515/jnet-2022-0098

D. Ladino-Luna, J. C. Chimal-Eguía, J. C. Pacheco-Paez, R. Páez-Hernández

引用次数: 4

Conservatively perturbed equilibrium in multi-route catalytic reactions 多路催化反应的保守微扰平衡

IF 6.6 3区工程技术

Journal of Non-Equilibrium Thermodynamics Pub Date : 2023-01-12 DOI: 10.1515/jnet-2022-0054

Vitaliy R. Trishch, G. Yablonsky, D. Constales, Y. Beznosyk

{"title":"Conservatively perturbed equilibrium in multi-route catalytic reactions","authors":"Vitaliy R. Trishch, G. Yablonsky, D. Constales, Y. Beznosyk","doi":"10.1515/jnet-2022-0054","DOIUrl":"https://doi.org/10.1515/jnet-2022-0054","url":null,"abstract":"Abstract The phenomenon of conservatively perturbed-equilibrium (CPE) in multi-route catalytic reactions was studied in the plug-flow reactor (PFR). The following multi-route mechanisms were chosen for studying, i.e., the two-route mechanism with the single common intermediate, the three-route mechanism with some common steps, and the two-route mechanism with the single common step and two common intermediates. All mentioned mechanisms exhibit the CPE-phenomenon. At given rate coefficients, the mechanism with the single common intermediate showed the greater CPE-effect than the mechanism with the common steps. A special computer experiment was performed in which the kinetic characteristics of non-catalytic and catalytic reactions have been compared. In this experiment, both non-catalytic and catalytic reactions have the same overall-reactions with the given equilibrium constant. It was shown that the absolute values of extreme concentrations at the CPE-point are almost the same. In this case, it is possible to estimate the concentrations at the CPE-values for complex reactions based on similar characteristics of the corresponding simple ones.","PeriodicalId":16428,"journal":{"name":"Journal of Non-Equilibrium Thermodynamics","volume":"48 1","pages":"229 - 241"},"PeriodicalIF":6.6,"publicationDate":"2023-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42999472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Natural convection of a viscoelastic Cattaneo–Christov fluid bounded by thick walls with finite thermal conductivity 热导率有限的厚壁粘弹性Cattaneo-Christov流体的自然对流

IF 6.6 3区工程技术

Journal of Non-Equilibrium Thermodynamics Pub Date : 2023-01-09 DOI: 10.1515/jnet-2022-0051

L. Dávalos-Orozco, Jose Antonio Ruiz Díaz

{"title":"Natural convection of a viscoelastic Cattaneo–Christov fluid bounded by thick walls with finite thermal conductivity","authors":"L. Dávalos-Orozco, Jose Antonio Ruiz Díaz","doi":"10.1515/jnet-2022-0051","DOIUrl":"https://doi.org/10.1515/jnet-2022-0051","url":null,"abstract":"Abstract The linear natural convection of a Maxwell viscoelastic fluid with Cattaneo–Christov heat flux constitutive equation, between two thick walls with finite thermal conductivity is investigated. The viscoelastic fluid and the heat flux have different relaxation times. The main interest is on the curves of criticality for different thicknesses ratio D and thermal conductivities ratio X. In the middle range of log X the curves of criticality stabilize depending on the other parameters of the problem. It is revealed that for some Prandtl numbers the curves of criticality remain higher for small X and lower for large X. However, increasing the Prandtl number this behavior is reversed. It is shown that this has important consequences in the order of the criticality curves when the heat flux relaxation time is increased. Depending on the Prandtl number, an increase of this relaxation time may decrease (destabilize) the curves of criticality until a minimum is reached, after which the curves start to increase (stabilize) again. For two different magnitudes of the viscoelastic relaxation time, the critical Rayleigh number, wavenumber and frequency of oscillation are plotted against log X for different magnitudes of D and the heat flux relaxation time.","PeriodicalId":16428,"journal":{"name":"Journal of Non-Equilibrium Thermodynamics","volume":"48 1","pages":"271 - 289"},"PeriodicalIF":6.6,"publicationDate":"2023-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43408006","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Impact of wavy porous layer on the hydrodynamic forces and heat transfer of hybrid nanofluid flow in a channel with cavity under the effect of partial magnetic field 部分磁场作用下波浪状多孔层对带腔通道内混合纳米流体流体动力及传热的影响

IF 6.6 3区工程技术

Journal of Non-Equilibrium Thermodynamics Pub Date : 2023-01-06 DOI: 10.1515/jnet-2022-0070

S. Hussain, M. A. Qureshi, Sameh E. Ahmed

{"title":"Impact of wavy porous layer on the hydrodynamic forces and heat transfer of hybrid nanofluid flow in a channel with cavity under the effect of partial magnetic field","authors":"S. Hussain, M. A. Qureshi, Sameh E. Ahmed","doi":"10.1515/jnet-2022-0070","DOIUrl":"https://doi.org/10.1515/jnet-2022-0070","url":null,"abstract":"Abstract This computational analysis focuses on the effects of porous layer on the flow dynamics, heat transfer and hydrodynamic forces of hybrid nanofluid in a channel having an open cavity fixed with bottom wall in the presence of partial magnetic field. The set of PDEs governing the dynamics has been transformed to dimensionless form and simulated using higher order finite element method. In particular, P 3 / P 2 ${mathbb{P}}_{3}/{mathbb{P}}_{2}$ finite element pair is employed for the spatial discretization and Crank–Nicolson approach is utilized for the temporal discretization. The obtained equations has been linearized with adaptive Newtons method and linearized systems have been computed using the geometric multi-grid technique. The impact of parameters, for instance, Richardson number, thickness of porous layer and nanoparticle fraction is analyzed in the presence of partial magnetic field and porous layer on the hydrodynamic forces like lift and drag forces on the submerged bodies, being the important part of the fluid flow and heat transfer are also be analysed. It is noticed that the drag and lift coefficients are reduced as the nanoparticle fraction is altered while the local- and average-Nusselt number get higher values.","PeriodicalId":16428,"journal":{"name":"Journal of Non-Equilibrium Thermodynamics","volume":"48 1","pages":"255 - 269"},"PeriodicalIF":6.6,"publicationDate":"2023-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44337852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

The Onsager–Machlup theory of fluctuations and time-dependent generalized normal distribution Onsager–Machlup涨落理论与含时广义正态分布

IF 6.6 3区工程技术

Journal of Non-Equilibrium Thermodynamics Pub Date : 2023-01-05 DOI: 10.1515/jnet-2022-0071

S. I. Serdyukov

引用次数: 0

New formulation of the Navier–Stokes equations for liquid flows 液体流动Navier-Stokes方程的新公式

IF 6.6 3区工程技术

Journal of Non-Equilibrium Thermodynamics Pub Date : 2022-12-16 DOI: 10.1515/jnet-2022-0095

M. Giona, Giuseppe Procopio, A. Adrover, R. Mauri

{"title":"New formulation of the Navier–Stokes equations for liquid flows","authors":"M. Giona, Giuseppe Procopio, A. Adrover, R. Mauri","doi":"10.1515/jnet-2022-0095","DOIUrl":"https://doi.org/10.1515/jnet-2022-0095","url":null,"abstract":"Abstract For isothermal liquid flows, the condition of incompressibility provides a useful simplification for describing their mechanical properties. Nevertheless, it overlooks acoustic effects, and it provides the unpleasant shortcoming of infinite propagation speed of velocity perturbations, no matter the type of constitutive equation for the shear stresses is adopted. In this paper, we provide a derivation of a new formulation of the Navier–Stokes equations for liquid flows that overcomes the above issues. The pressure looses its ancillary status of mere gauge variable (or equivalently Lagrange multiplier of the incompressibility condition) enforcing the solenoidal nature of the velocity field, and attains the proper physical meaning of hydrodynamic field variable characterized by its own spatiotemporal evolution. From the experimental evidence of sound attenuation, related to the occurrence of a non-vanishing bulk viscosity, the evolution equation for pressure in out-of-equilibrium conditions is derived without introducing any adjustable parameters. The connection between compressibility and memory effects in the propagation of internal stresses is established. Normal mode analysis and some preliminary simulations are also discussed.","PeriodicalId":16428,"journal":{"name":"Journal of Non-Equilibrium Thermodynamics","volume":"48 1","pages":"207 - 228"},"PeriodicalIF":6.6,"publicationDate":"2022-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49336616","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Are all chemical reactions in principle reversible? Thermodynamic distinction between “conceptually complete” and “practically complete” reactions 所有的化学反应原则上都是可逆的吗?“概念完全”和“实际完全”反应之间的热力学区别

IF 6.6 3区工程技术

Journal of Non-Equilibrium Thermodynamics Pub Date : 2022-12-13 DOI: 10.1515/jnet-2022-0044

A. Ciccioli

{"title":"Are all chemical reactions in principle reversible? Thermodynamic distinction between “conceptually complete” and “practically complete” reactions","authors":"A. Ciccioli","doi":"10.1515/jnet-2022-0044","DOIUrl":"https://doi.org/10.1515/jnet-2022-0044","url":null,"abstract":"Abstract Among the chemical reactions having a pronounced thermodynamic driving force to the formation of products, a distinction has to be made between processes which attain a chemical equilibrium state very much shifted towards the products and those where the final equilibrium state corresponds to the truly complete consumption of reactant(s), i.e. where a true chemical equilibrium is actually not attained under the given conditions. Based on a few selected examples, two thermodynamic arguments are led which rationalise the above distinction from different points of view: a phase-rule point of view and a Gibbs energy minimization approach. “Conceptually complete” reactions involve pure phases and, as a consequence, establishing chemical equilibrium would imply a negative variance, what is avoided by the complete consumption of one or more phases. In the Gibbs energy approach, “conceptually complete” reactions and “practically complete” ones can be distinguished (at fixed temperature and pressure) by the different way to attain the minimum Gibbs energy condition, respectively with sharp (not differentiable) and flat (zero derivative) minimum points as a function of the extent of reaction ξ.","PeriodicalId":16428,"journal":{"name":"Journal of Non-Equilibrium Thermodynamics","volume":"48 1","pages":"195 - 206"},"PeriodicalIF":6.6,"publicationDate":"2022-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49058590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Maximum ecological function performance for a three-reservoir endoreversible chemical pump 三储层内可逆化学泵的最大生态功能性能

IF 6.6 3区工程技术

Journal of Non-Equilibrium Thermodynamics Pub Date : 2022-12-07 DOI: 10.1515/jnet-2022-0062

Lingen Chen, Shuangshuang Shi, H. Feng, Y. Ge

{"title":"Maximum ecological function performance for a three-reservoir endoreversible chemical pump","authors":"Lingen Chen, Shuangshuang Shi, H. Feng, Y. Ge","doi":"10.1515/jnet-2022-0062","DOIUrl":"https://doi.org/10.1515/jnet-2022-0062","url":null,"abstract":"Abstract Endoreversible chemical pump (ECP) is a theoretical model of electrochemical, photochemical, solid-state apparatus and mass exchangers. ECP can be classified as two-, three- and four-mass-reservoir devices. The usual performance indicators for ECPs are energy pumping rate (EPR) and coefficient of performance (COP). Energy-based ecological function objective (EFO) is introduced to performance optimization of three-reservoir ECP. Optimization relationships between EFO and COP with linear and diffusive mass transfer laws (MTLs) are deduced. Numerical examples are provided, and influences of cycle parameters and MTLs on optimal EFO performances are analyzed. For linear MTL, compared performances at maximum EFO point and point where dimensionless EPR is 0.016, COP increases 14.4% and entropy generation rate (EGR) drops 52% with only 30% loss of EPR. For diffusive MTL, compared performances at maximum dimensionless EFO point and point where dimensionless EPR is 0.01, COP increases 11.3% and EGR drops 46.9% with only 30% loss of EPR. It demonstrates that EFO is a trade-off between EPR and dissipation of EPR, which is beneficial to utilize energy effectively. With the same chemical potentials of three reservoirs, the maximum dimensionless EFO and the corresponding COP with linear MTL are bigger than those with diffusive MTL.","PeriodicalId":16428,"journal":{"name":"Journal of Non-Equilibrium Thermodynamics","volume":"48 1","pages":"179 - 194"},"PeriodicalIF":6.6,"publicationDate":"2022-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42777760","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 12

Non-equilibrium thermodynamics modelling of the stress-strain relationship in soft two-phase elastic-viscoelastic materials 软质两相弹性粘弹性材料应力-应变关系的非平衡热力学模型

IF 6.6 3区工程技术

Journal of Non-Equilibrium Thermodynamics Pub Date : 2022-12-05 DOI: 10.1515/jnet-2022-0069

Pavlos S. Stephanou, P. Vafeas, V. Mavrantzas

{"title":"Non-equilibrium thermodynamics modelling of the stress-strain relationship in soft two-phase elastic-viscoelastic materials","authors":"Pavlos S. Stephanou, P. Vafeas, V. Mavrantzas","doi":"10.1515/jnet-2022-0069","DOIUrl":"https://doi.org/10.1515/jnet-2022-0069","url":null,"abstract":"Abstract In “soft–soft nanocomposites” based on film formation of latexes with structured particles, the combination of particle structure and interparticle crosslinking leads to materials that behave as nonlinear viscoelastic fluids at small strains and as highly elastic networks at larger strains. Similarly, in studies of flow-induced crystallization in polymers, a two-phase model is often invoked in which a soft viscoelastic component is coupled with a rigid semi-crystalline phase providing stiffness. In the present work, we use the framework of non-equilibrium thermodynamics (NET) to develop stress-strain relationships for such two-phase systems characterized by a viscoelastic and an elastic component by making use of two conformation tensors: the first describes the microstructure of the viscoelastic phase while the second is related to the elastic Finger strain tensor quantifying the deformation of the elastic phase due to strain and is responsible for strain-hardening. The final transport equations are formulated in the context of the generalized bracket formalism of NET and can describe the rheological behavior and mechanical response of a large variety of soft materials ranging from rubbers to artificial tissues.","PeriodicalId":16428,"journal":{"name":"Journal of Non-Equilibrium Thermodynamics","volume":"48 1","pages":"91 - 105"},"PeriodicalIF":6.6,"publicationDate":"2022-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46637219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Nonlinear dynamics of blood passing through an overlapped stenotic artery with copper nanoparticles 非线性动力学的血液通过重叠狭窄动脉与铜纳米颗粒

IF 6.6 3区工程技术

Journal of Non-Equilibrium Thermodynamics Pub Date : 2022-12-05 DOI: 10.1515/jnet-2022-0063

Hanumesh Vaidya, I. L. Animasaun, K. Prasad, C. Rajashekhar, J. U. Viharika, Q. Al‐Mdallal

{"title":"Nonlinear dynamics of blood passing through an overlapped stenotic artery with copper nanoparticles","authors":"Hanumesh Vaidya, I. L. Animasaun, K. Prasad, C. Rajashekhar, J. U. Viharika, Q. Al‐Mdallal","doi":"10.1515/jnet-2022-0063","DOIUrl":"https://doi.org/10.1515/jnet-2022-0063","url":null,"abstract":"Abstract The dynamics of blood carrying microscopic copper particles through overlapping stenotic arteries is an important research area needed for scrutinizing and exploring dynamics through blood vessels. Adipose tissue deposition and other elements of atherosclerosis generate the uncommon artery disease known as arterial stenosis. It limits blood flow and raises the risk of heart disease. Using the Casson model, it is feasible to shed light on the peristaltic blood flow of copper nanoparticles over an overlapping stenotic artery. Nothing is known about the study of heat sink/source, buoyancy and Lorent force, and volume fraction because the focus is on the dynamics of blood carrying minute copper particles through an overlapping stenotic artery. When the Lorentz force is significant, the transport mentioned above was evaluated utilizing stenosis approximations to examine the stream function, wall shear stress, Nusselt number, and flow resistance distribution. In addition, temperature solutions were identified analytically, whereas a perturbation approach acquired velocity solutions. Temperature distribution and velocity are greater in stenosed arteries than in unstenosed arteries. Furthermore, extreme velocity and temperature rise as it reaches the core of the artery and falls as one approaches the wall. When the heat source parameter values increase due to an improvement in the fluid’s thermal state, the temperature distribution increases.","PeriodicalId":16428,"journal":{"name":"Journal of Non-Equilibrium Thermodynamics","volume":"48 1","pages":"159 - 178"},"PeriodicalIF":6.6,"publicationDate":"2022-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47004450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6