Combining finite time thermodynamics and exergetic analysis, analogous to the definition of ecological efficient power for heat engines, this paper proposes a unified performance indicator for various cycles, exergy-based efficient ecological function (Eɛ) which is defined as product of exergy-based ecological function and coefficient of performance, and introduces it into performance optimization of endoreversible simple air refrigerator cycle coupled to constant-temperature heat reservoirs. Relations among Eɛ, pressure ratio (π) and heat conductance distribution ratio (u) are derived by using numerical method. The cycle performance indicators which include cooling load (R), coefficient of performance (ɛ), and exergetic loss rate (Eout/T0) under the different maximum objective criteria are compared. Taking π as optimal variable, and taking R, ɛ, cooling load density (r), Eɛ and their combinations as optimization objectives, multi-objective optimizations, totally 15 optimization combinations, are performed by using NASG-II algorithm. The results demonstrate that, the maximum Eɛ criteria can better reflect the compromise among R, ɛ and Eout/T0. The Pareto solution sets are majorly distributed in 2.5–20 when quadru-objective optimizations are performed. The option selected by LINMAP decision-making method is closer to ideal solution when bi-objective optimization of ɛ and r is carried out.
本文结合有限时间热力学和能效分析,类比热机生态效率功率的定义,提出了各种循环的统一性能指标--基于能效的高效生态函数(E ɛ ),定义为基于能效的生态函数与性能系数的乘积,并将其引入到与恒温蓄热器耦合的内逆简单空气制冷循环的性能优化中。通过数值方法推导出 E ɛ、压力比 (π) 和热传导分布比 (u) 之间的关系。比较了不同最大目标标准下的循环性能指标,包括冷却负荷(R)、性能系数(ɛ)和能效损失率(E out/T 0)。以 π 为最优变量,以 R、ɛ、冷却负荷密度 (r)、E ɛ 及其组合为优化目标,采用 NASG-II 算法进行多目标优化,共优化组合 15 个。结果表明,最大 E ɛ 标准能较好地反映 R、ɛ 和 E out/T 0 之间的折衷关系,在进行四目标优化时,帕累托解集主要分布在 2.5-20 之间。当对 ɛ 和 r 进行双目标优化时,LINMAP 决策方法选择的方案更接近理想方案。
{"title":"Efficient ecological function analysis and multi-objective optimizations for an endoreversible simple air refrigerator cycle","authors":"Zijian Xu, Yanlin Ge, Lingen Chen, Huijun Feng","doi":"10.1515/jnet-2024-0045","DOIUrl":"https://doi.org/10.1515/jnet-2024-0045","url":null,"abstract":"Combining finite time thermodynamics and exergetic analysis, analogous to the definition of ecological efficient power for heat engines, this paper proposes a unified performance indicator for various cycles, exergy-based efficient ecological function (<jats:italic>E</jats:italic> <jats:sub> <jats:italic>ɛ</jats:italic> </jats:sub>) which is defined as product of exergy-based ecological function and coefficient of performance, and introduces it into performance optimization of endoreversible simple air refrigerator cycle coupled to constant-temperature heat reservoirs. Relations among <jats:italic>E</jats:italic> <jats:sub> <jats:italic>ɛ</jats:italic> </jats:sub>, pressure ratio (<jats:italic>π</jats:italic>) and heat conductance distribution ratio (<jats:italic>u</jats:italic>) are derived by using numerical method. The cycle performance indicators which include cooling load (<jats:italic>R</jats:italic>), coefficient of performance (<jats:italic>ɛ</jats:italic>), and exergetic loss rate (<jats:italic>E</jats:italic> <jats:sub>out</jats:sub>/<jats:italic>T</jats:italic> <jats:sub>0</jats:sub>) under the different maximum objective criteria are compared. Taking <jats:italic>π</jats:italic> as optimal variable, and taking <jats:italic>R</jats:italic>, <jats:italic>ɛ</jats:italic>, cooling load density (<jats:italic>r</jats:italic>), <jats:italic>E</jats:italic> <jats:sub> <jats:italic>ɛ</jats:italic> </jats:sub> and their combinations as optimization objectives, multi-objective optimizations, totally 15 optimization combinations, are performed by using NASG-II algorithm. The results demonstrate that, the maximum <jats:italic>E</jats:italic> <jats:sub> <jats:italic>ɛ</jats:italic> </jats:sub> criteria can better reflect the compromise among <jats:italic>R</jats:italic>, <jats:italic>ɛ</jats:italic> and <jats:italic>E</jats:italic> <jats:sub>out</jats:sub>/<jats:italic>T</jats:italic> <jats:sub>0</jats:sub>. The Pareto solution sets are majorly distributed in 2.5–20 when quadru-objective optimizations are performed. The option selected by LINMAP decision-making method is closer to ideal solution when bi-objective optimization of <jats:italic>ɛ</jats:italic> and <jats:italic>r</jats:italic> is carried out.","PeriodicalId":16428,"journal":{"name":"Journal of Non-Equilibrium Thermodynamics","volume":"3 1","pages":""},"PeriodicalIF":6.6,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142379266","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}
A novel modeling and new irreversibility analysis of non-homogeneous charged gas flow is presented as an extension and further development of our previous article [J. Non-equilibrium. Thermodyne. 49 (2024), 1–21]. We study the non-equilibrium irreversible thermodynamics (NIT) properties of the exact solution to the dilute non-homogeneously charged gas problem with unsteady Rayleigh flow. In contrast to previous research, the charged gas is non-homogeneous under the influence of induced electromagnetic forces, the flat plate moving damping with time, and the effect of positive ions is considered, leading to significant advancements in understanding natural plasma dynamics. We are solving eight non-homogeneous partial differential equations (PDE). We used a Laplace transformation technique and small parameters methods. To the best of our knowledge, as two new scientific achievements, we introduced a new mathematical model for a mixture of charged gas to calculate the thermodynamic forces, kinetic coefficients, and fluxes variables, see Appendices. Second, we present a fantastic new technique by a flowchart to identify the equilibrium time of multi-component plasma step-by-step using the velocity distribution function (VDF). We indicate that electrons, which are faster lighter components, reach equilibrium faster than slower heavier components. A standard laboratory argon plasma model is used to apply the results.
{"title":"Novel irreversibility modeling of non-homogeneous charged gas flow by solving Maxwell–Boltzmann PDEs system: irreversibility analysis for multi-component plasma","authors":"Taha Z. Abdel Wahid, Zaki Mrzog Alaofi","doi":"10.1515/jnet-2024-0055","DOIUrl":"https://doi.org/10.1515/jnet-2024-0055","url":null,"abstract":"A novel modeling and new irreversibility analysis of non-homogeneous charged gas flow is presented as an extension and further development of our previous article [J. Non-equilibrium. Thermodyne. 49 (2024), 1–21]. We study the non-equilibrium irreversible thermodynamics (NIT) properties of the exact solution to the dilute non-homogeneously charged gas problem with unsteady Rayleigh flow. In contrast to previous research, the charged gas is non-homogeneous under the influence of induced electromagnetic forces, the flat plate moving damping with time, and the effect of positive ions is considered, leading to significant advancements in understanding natural plasma dynamics. We are solving eight non-homogeneous partial differential equations (PDE). We used a Laplace transformation technique and small parameters methods. To the best of our knowledge, as two new scientific achievements, we introduced a new mathematical model for a mixture of charged gas to calculate the thermodynamic forces, kinetic coefficients, and fluxes variables, see Appendices. Second, we present a fantastic new technique by a flowchart to identify the equilibrium time of multi-component plasma step-by-step using the velocity distribution function (VDF). We indicate that electrons, which are faster lighter components, reach equilibrium faster than slower heavier components. A standard laboratory argon plasma model is used to apply the results.","PeriodicalId":16428,"journal":{"name":"Journal of Non-Equilibrium Thermodynamics","volume":"67 1","pages":""},"PeriodicalIF":6.6,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142325015","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}
Réka Somogyfoki, Alessio Famá, Liliana Restuccia, Peter Ván
The stability of homogeneous thermodynamic equilibrium is analyzed in heat conduction theories in the framework of nonequilibrium thermodynamics, where the internal energy, the heat flux and a second order tensor are thermodynamic state variables. It is shown, that the thermodynamic conditions of concave entropy and nonnegative entropy production can ensure the linear stability. Various special heat conduction theories, including Extended Thermodynamics, are compared in the general framework.
{"title":"Thermodynamics and dynamic stability: extended theories of heat conduction","authors":"Réka Somogyfoki, Alessio Famá, Liliana Restuccia, Peter Ván","doi":"10.1515/jnet-2024-0041","DOIUrl":"https://doi.org/10.1515/jnet-2024-0041","url":null,"abstract":"The stability of homogeneous thermodynamic equilibrium is analyzed in heat conduction theories in the framework of nonequilibrium thermodynamics, where the internal energy, the heat flux and a second order tensor are thermodynamic state variables. It is shown, that the thermodynamic conditions of concave entropy and nonnegative entropy production can ensure the linear stability. Various special heat conduction theories, including Extended Thermodynamics, are compared in the general framework.","PeriodicalId":16428,"journal":{"name":"Journal of Non-Equilibrium Thermodynamics","volume":"6 1","pages":""},"PeriodicalIF":6.6,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142317728","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}
We investigate the optimal performance of the quantum Otto engine and refrigeration cycles of a time-dependent harmonic oscillator under a trade-off figure of merit for both adiabatic and nonadiabatic (sudden-switch) frequency modulations. For heat engines (refrigerators), the chosen trade-off figure of merit is an objective function defined by the product of efficiency (coefficient of performance) and work output (cooling load), thus representing a compromise between them. We obtain analytical expressions for the efficiency and coefficient of performance of the harmonic Otto cycle for the optimal performance of the thermal machine in various operational regimes. Particularly, in the sudden-switch regime, we discuss the implications of the nonadiabatic driving on the performance of the thermal machine under consideration and obtain analytic expressions for the maximum achievable efficiency and coefficient of performance of the harmonic Otto thermal machine. Particularly, we show that the quantum harmonic Otto cycle driven by sudden-switch protocol cannot work as a heat engine or refrigerator in the low-temperature limit. Finally, we show that in the high-temperature limit, the frictional effects give rise to a richer structure of the phase diagram of the harmonic Otto cycle. We identify the parametric regime for the operation of the Otto cycle as a heat engine, refrigerator, accelerator, and heater.
{"title":"Performance analysis of quantum harmonic Otto engine and refrigerator under a trade-off figure of merit","authors":"Kirandeep Kaur, Shishram Rebari, Varinder Singh","doi":"10.1515/jnet-2024-0034","DOIUrl":"https://doi.org/10.1515/jnet-2024-0034","url":null,"abstract":"We investigate the optimal performance of the quantum Otto engine and refrigeration cycles of a time-dependent harmonic oscillator under a trade-off figure of merit for both adiabatic and nonadiabatic (sudden-switch) frequency modulations. For heat engines (refrigerators), the chosen trade-off figure of merit is an objective function defined by the product of efficiency (coefficient of performance) and work output (cooling load), thus representing a compromise between them. We obtain analytical expressions for the efficiency and coefficient of performance of the harmonic Otto cycle for the optimal performance of the thermal machine in various operational regimes. Particularly, in the sudden-switch regime, we discuss the implications of the nonadiabatic driving on the performance of the thermal machine under consideration and obtain analytic expressions for the maximum achievable efficiency and coefficient of performance of the harmonic Otto thermal machine. Particularly, we show that the quantum harmonic Otto cycle driven by sudden-switch protocol cannot work as a heat engine or refrigerator in the low-temperature limit. Finally, we show that in the high-temperature limit, the frictional effects give rise to a richer structure of the phase diagram of the harmonic Otto cycle. We identify the parametric regime for the operation of the Otto cycle as a heat engine, refrigerator, accelerator, and heater.","PeriodicalId":16428,"journal":{"name":"Journal of Non-Equilibrium Thermodynamics","volume":"5 1","pages":""},"PeriodicalIF":6.6,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142090068","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}
This study investigates the effects of using biodiesel from Mesua ferrea (BD20) and chromium oxide (Cr2O3) nanoparticles in diesel engines. The Response Surface Methodology (RSM) model and artificial neural networks (ANNs) were developed to make precise predictions of the operating parameters. The amount of Cr2O3 nanoparticles was set at 80 mg/L, and surfactant and dispersant were applied to the nanoparticles in the same amounts. The study was carried out with different compression ratios and load conditions. The parameters evaluated were engine load, fuel samples and compression ratio as inputs and BTE, BSFC, CP, NHRR, CO, UHC, NOx and smoke opacity as outputs. The addition of the QPAN80 additive at the same dosage of 80 mg/L together with the BD20 fuel blend containing Cr2O3 at a concentration of 80 mg/L resulted in a significant increase in BTE by 16.58 % and a reduction in BSFC by 0.58 %. While the NHRR increased by 85.40 %, the CP increased sharply by 24.47 %. The CO concentration decreased by 31.85 %, the UHC concentration by 22.22 %, the NOx concentration by 6.16 % and the smoke emission by 62.61 %. For each output parameter, the correlation coefficient (R2), calculated using ANNs and RSM was between 0.96 and 0.98. The observed range of values demonstrates a robust correlation between the experimental data and the predicted outcomes.
{"title":"Investigation of the operating characteristics of diesel engines with chromium oxide (Cr2O3) nanoparticles dispersed in Mesua ferrea biodiesel: an experimental and predictive approach using ANNs and RSM","authors":"Jagadish Kari, Vanthala Varaha Siva Prasad, Jaikumar Sagari","doi":"10.1515/jnet-2024-0021","DOIUrl":"https://doi.org/10.1515/jnet-2024-0021","url":null,"abstract":"This study investigates the effects of using biodiesel from <jats:italic>Mesua ferrea</jats:italic> (BD20) and chromium oxide (Cr<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>) nanoparticles in diesel engines. The Response Surface Methodology (RSM) model and artificial neural networks (ANNs) were developed to make precise predictions of the operating parameters. The amount of Cr<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> nanoparticles was set at 80 mg/L, and surfactant and dispersant were applied to the nanoparticles in the same amounts. The study was carried out with different compression ratios and load conditions. The parameters evaluated were engine load, fuel samples and compression ratio as inputs and BTE, BSFC, CP, NHRR, CO, UHC, NO<jats:sub> <jats:italic>x</jats:italic> </jats:sub> and smoke opacity as outputs. The addition of the QPAN80 additive at the same dosage of 80 mg/L together with the BD20 fuel blend containing Cr<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> at a concentration of 80 mg/L resulted in a significant increase in BTE by 16.58 % and a reduction in BSFC by 0.58 %. While the NHRR increased by 85.40 %, the CP increased sharply by 24.47 %. The CO concentration decreased by 31.85 %, the UHC concentration by 22.22 %, the NO<jats:sub> <jats:italic>x</jats:italic> </jats:sub> concentration by 6.16 % and the smoke emission by 62.61 %. For each output parameter, the correlation coefficient (<jats:italic>R</jats:italic> <jats:sup>2</jats:sup>), calculated using ANNs and RSM was between 0.96 and 0.98. The observed range of values demonstrates a robust correlation between the experimental data and the predicted outcomes.","PeriodicalId":16428,"journal":{"name":"Journal of Non-Equilibrium Thermodynamics","volume":"23 1","pages":""},"PeriodicalIF":6.6,"publicationDate":"2024-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141994468","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}
This paper presents mathematical responses for the dual-phase-lag (DPL) hypothesis, which accounts for nonequilibrium heat transfer during magnetic nanoparticle hyperthermia in tumor. To get this precision, volume averaging is used for the local instantaneous energy formulation for tissues and blood. This study proposes a hybrid numerical strategy to solve this problem by combining change of variables, improved discretization techniques, and Laplace transforms. Using the Arrhenius formulas, the range of denatured proteins is used to assess the degree of heat damages to the tumor and healthy tissues. The impacts of porosity, the blood perfusion and metabolism on the temperature and the thermal injuries are studied. The numerical estimations of temperature and the resulting of thermal injuries are shown on a graph, and a comparison with earlier research establishes the results’ validity.
{"title":"Analytical solutions for nonequilibrium bioheat transfer in tumor during magnetic nanoparticles hyperthermia","authors":"Zuhur Alqahtani, Ibrahim Abbas","doi":"10.1515/jnet-2024-0035","DOIUrl":"https://doi.org/10.1515/jnet-2024-0035","url":null,"abstract":"This paper presents mathematical responses for the dual-phase-lag (DPL) hypothesis, which accounts for nonequilibrium heat transfer during magnetic nanoparticle hyperthermia in tumor. To get this precision, volume averaging is used for the local instantaneous energy formulation for tissues and blood. This study proposes a hybrid numerical strategy to solve this problem by combining change of variables, improved discretization techniques, and Laplace transforms. Using the Arrhenius formulas, the range of denatured proteins is used to assess the degree of heat damages to the tumor and healthy tissues. The impacts of porosity, the blood perfusion and metabolism on the temperature and the thermal injuries are studied. The numerical estimations of temperature and the resulting of thermal injuries are shown on a graph, and a comparison with earlier research establishes the results’ validity.","PeriodicalId":16428,"journal":{"name":"Journal of Non-Equilibrium Thermodynamics","volume":"80 1","pages":""},"PeriodicalIF":6.6,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141755075","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}
The article analyses the degree of water superheating with respect to the liquid-vapour equilibrium line in experiments on the micro-explosion of a composite droplet comprised of two immiscible liquids. The analyses were carried out for water-in-fuel drops under conditions of high-power heating. This degree is compared with the mechanical effect of droplet decay, involving the formation of daughter droplets. Our attention was drawn to the smallness of the degree of superheating preceding the decay. A model of the boiling up of such a droplet is constructed taking into account the sources of premature boiling up of water inherent in micro-explosive experiments. The dependencies of the boiling up temperature of water on the heating rate obtained in the model turned out to be in accordance with the experimental data across a wide range of heating rates. A hypothesis about the local superheating of the transition layer, which is not detected in the experiment, is formulated. Thus, a step has been taken to clarify the essence of the mismatch of the degree of superheating of water recorded by macroscopic equipment along with a completely satisfactory generation of daughter droplets serving as the basis for advanced fuel technology.
{"title":"Composite liquids under high-power heating: superheat of water in micro-explosion of water-in-fuel droplets","authors":"Alexey Melkikh, Pavel Skripov","doi":"10.1515/jnet-2024-0017","DOIUrl":"https://doi.org/10.1515/jnet-2024-0017","url":null,"abstract":"The article analyses the degree of water superheating with respect to the liquid-vapour equilibrium line in experiments on the micro-explosion of a composite droplet comprised of two immiscible liquids. The analyses were carried out for water-in-fuel drops under conditions of high-power heating. This degree is compared with the mechanical effect of droplet decay, involving the formation of daughter droplets. Our attention was drawn to the smallness of the degree of superheating preceding the decay. A model of the boiling up of such a droplet is constructed taking into account the sources of premature boiling up of water inherent in micro-explosive experiments. The dependencies of the boiling up temperature of water on the heating rate obtained in the model turned out to be in accordance with the experimental data across a wide range of heating rates. A hypothesis about the local superheating of the transition layer, which is not detected in the experiment, is formulated. Thus, a step has been taken to clarify the essence of the mismatch of the degree of superheating of water recorded by macroscopic equipment along with a completely satisfactory generation of daughter droplets serving as the basis for advanced fuel technology.","PeriodicalId":16428,"journal":{"name":"Journal of Non-Equilibrium Thermodynamics","volume":"51 1","pages":""},"PeriodicalIF":6.6,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141755085","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}
We discuss the application of the three-laser optical digital interferometry method for the determination of transport properties such as the thermodiffusion, the molecular diffusion and the Soret coefficients by the thermogravitational column technique. The primary objective of this study is to illustrate the capabilities and limitations of the method for quantifying these properties in both binary and ternary liquid mixtures from an optical viewpoint. It is concluded that the system is highly robust for the analysis of binary mixtures, with the combination of the results obtained by the three wavelengths increasing the accuracy of the measurement. The study of ternary mixtures, on the contrary, is limited to certain types of conditions. While the accuracy of a three-laser interferometer can be improved, the method may be compromised if the optical contrast factor matrices are poorly conditioned.
{"title":"Application of a three-laser optical digital interferometry in a thermogravitational analysis for binary and ternary mixtures","authors":"Ane Errarte, Antton Sanjuan, Aliaksandr Mialdun, Marcos Alonso, Imanol Andonegui, Valentina Shevtsova, M. Mounir Bou-Ali","doi":"10.1515/jnet-2023-0126","DOIUrl":"https://doi.org/10.1515/jnet-2023-0126","url":null,"abstract":"We discuss the application of the three-laser optical digital interferometry method for the determination of transport properties such as the thermodiffusion, the molecular diffusion and the Soret coefficients by the thermogravitational column technique. The primary objective of this study is to illustrate the capabilities and limitations of the method for quantifying these properties in both binary and ternary liquid mixtures from an optical viewpoint. It is concluded that the system is highly robust for the analysis of binary mixtures, with the combination of the results obtained by the three wavelengths increasing the accuracy of the measurement. The study of ternary mixtures, on the contrary, is limited to certain types of conditions. While the accuracy of a three-laser interferometer can be improved, the method may be compromised if the optical contrast factor matrices are poorly conditioned.","PeriodicalId":16428,"journal":{"name":"Journal of Non-Equilibrium Thermodynamics","volume":"240 1","pages":""},"PeriodicalIF":6.6,"publicationDate":"2024-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141631399","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}
In many industrial applications as well as in nature, the mass transfer of CO2 at vapor-liquid interfaces in aqueous systems plays an important role. In this work, this process was studied on the atomistic level using non-equilibrium molecular dynamics simulations. In a first step, a molecular model of the system water + CO2 was developed that represents both bulk and interfacial equilibrium properties well. This system is characterized by a very large adsorption and enrichment of CO2 at the vapor-liquid interface. Then, non-equilibrium mass transfer simulations were carried out using a method that was developed recently: CO2 is inserted into the vapor phase of a simulation box which contains a liquid slab. Surprising effects are observed at the interface such as a net repulsion of CO2 particles from the interface and a complex time dependence of the amount of CO2 adsorbed at the interface.
在许多工业应用和自然界中,二氧化碳在水性体系的汽液界面上的传质都发挥着重要作用。在这项工作中,我们利用非平衡分子动力学模拟在原子水平上研究了这一过程。首先,我们建立了水 + CO2 系统的分子模型,该模型能很好地反映体液和界面的平衡特性。该系统的特点是二氧化碳在汽液界面上的大量吸附和富集。然后,使用最近开发的一种方法进行了非平衡传质模拟:在包含液态板坯的模拟箱中的气相中加入二氧化碳。在界面上观察到了令人惊讶的效应,如二氧化碳颗粒对界面的净排斥以及界面上二氧化碳吸附量的复杂时间依赖性。
{"title":"Mass transfer at vapor-liquid interfaces of H2O + CO2 mixtures studied by molecular dynamics simulation","authors":"Simon Stephan, Vilde Bråten, Hans Hasse","doi":"10.1515/jnet-2024-0010","DOIUrl":"https://doi.org/10.1515/jnet-2024-0010","url":null,"abstract":"In many industrial applications as well as in nature, the mass transfer of CO<jats:sub>2</jats:sub> at vapor-liquid interfaces in aqueous systems plays an important role. In this work, this process was studied on the atomistic level using non-equilibrium molecular dynamics simulations. In a first step, a molecular model of the system water + CO<jats:sub>2</jats:sub> was developed that represents both bulk and interfacial equilibrium properties well. This system is characterized by a very large adsorption and enrichment of CO<jats:sub>2</jats:sub> at the vapor-liquid interface. Then, non-equilibrium mass transfer simulations were carried out using a method that was developed recently: CO<jats:sub>2</jats:sub> is inserted into the vapor phase of a simulation box which contains a liquid slab. Surprising effects are observed at the interface such as a net repulsion of CO<jats:sub>2</jats:sub> particles from the interface and a complex time dependence of the amount of CO<jats:sub>2</jats:sub> adsorbed at the interface.","PeriodicalId":16428,"journal":{"name":"Journal of Non-Equilibrium Thermodynamics","volume":"26 1","pages":""},"PeriodicalIF":6.6,"publicationDate":"2024-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141631476","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}
Giuseppe Colella, Allan D. Mackie, James P. Larentzos, John K. Brennan, Martin Lísal, Josep Bonet Avalos
The complete description of energy and material transport within the Generalized energy-conserving dissipative particle dynamics with mass transfer (GenDPDE-M) methodology is presented. In particular, the dynamic coupling between mass and energy is incorporated into the GenDPDE-M, which was previously introduced with dynamically decoupled fluxes (J. Bonet Avalos et al., J. Chem. Theory Comput., 18 (12): 7639–7652, 2022). From a theoretical perspective, we have derived the appropriate Fluctuation-Dissipation theorems along with Onsager’s reciprocal relations, suitable for mesoscale models featuring this coupling. Equilibrium and non-equilibrium simulations are performed to demonstrate the internal thermodynamic consistency of the method, as well as the ability to capture the Ludwig–Soret effect, and tune its strength through the mesoscopic parameters. In view of the completeness of the presented approach, GenDPDE-M is the most general Lagrangian method to deal with complex fluids and systems at the mesoscale, where thermal agitation is relevant.
{"title":"Generalized energy-conserving dissipative particle dynamics with mass transfer: coupling between energy and mass exchange","authors":"Giuseppe Colella, Allan D. Mackie, James P. Larentzos, John K. Brennan, Martin Lísal, Josep Bonet Avalos","doi":"10.1515/jnet-2023-0129","DOIUrl":"https://doi.org/10.1515/jnet-2023-0129","url":null,"abstract":"The complete description of energy and material transport within the Generalized energy-conserving dissipative particle dynamics with mass transfer (GenDPDE-M) methodology is presented. In particular, the dynamic coupling between mass and energy is incorporated into the GenDPDE-M, which was previously introduced with dynamically decoupled fluxes (J. Bonet Avalos et al., <jats:italic>J. Chem. Theory Comput.</jats:italic>, 18 (12): 7639–7652, 2022). From a theoretical perspective, we have derived the appropriate Fluctuation-Dissipation theorems along with Onsager’s reciprocal relations, suitable for mesoscale models featuring this coupling. Equilibrium and non-equilibrium simulations are performed to demonstrate the internal thermodynamic consistency of the method, as well as the ability to capture the Ludwig–Soret effect, and tune its strength through the mesoscopic parameters. In view of the completeness of the presented approach, GenDPDE-M is the most general Lagrangian method to deal with complex fluids and systems at the mesoscale, where thermal agitation is relevant.","PeriodicalId":16428,"journal":{"name":"Journal of Non-Equilibrium Thermodynamics","volume":"20 1","pages":""},"PeriodicalIF":6.6,"publicationDate":"2024-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141182431","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}