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- Keyword
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- Chemical reaction; Heat and mass transfer; Thermodynamic coupling; Non-equilibrium thermodynamics (2)
- Column grand composite curves (2)
- Exergy loss (2)
- Retrofitting (2)
- Thermodynamic analysis (2)
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- Activity coefficient; Infinite dilution; UNIFAC; UNIFAC FV (1)
- And biological systems (1)
- Asymmetr heating (1)
- Balance equations; Reaction-transport systems; Thermodynamic coupling; Nonequilibrium thermodynamics; Degree of coupling (1)
- Binary liquid mixtures; NRTL and UNIQUAC models; Surfaces of derivative properties (1)
- Biodiesel; Direct Carboxylation; Glycerolysis; Glycerol Carbonate; Economic Analysis (1)
- Chemical (1)
- Coutte flow (1)
- Entropy generation (1)
- Entropy of vaporization; Azeotropic mixtures; Heat of vaporization (1)
- Forced convection (1)
- Information theory; biological systems; fluctuation theorem; thermodynamic coupling (1)
- Irreversibility distribution ratio (1)
- Latent heat storage; exergy analysis; thermoeconomics; discounted cash-flow diagram (1)
- Nonequilibrium Thermodynamics (1)
- Numerical analysis (1)
- Packed duct (1)
- Phase stability; Interval Newton method; NRTL model (1)
- Rarefied gas heat transfer; thermal insulator; free conduction regime; thermal accommodation coefficient (1)
- Thermodynamic analysis; Entropy generation; Annular packed bed; Asymmetric heating; Bejan number (1)
- Thermodynamic efficiency. (1)
- Thermodynmaic efficiency (1)
- Thermomechanical coupling (1)
- Transport and rate processes in physical (1)
- Publication Year
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Linear-Nonequilibrium Thermodynamics Theory For Coupled Heat And Mass Transport, Yasar Demirel, Stanley I. Sandler
Linear-Nonequilibrium Thermodynamics Theory For Coupled Heat And Mass Transport, Yasar Demirel, Stanley I. Sandler
YASAR DEMIREL
Linear-nonequilibrium thermodynamics (LNET) has been used to express the entropy generation and dissipation functions representing the true forces and flows for heat and mass transport in a multicomponent fluid. These forces and flows are introduced into the phenomenological equations to formulate the coupling phenomenon between heat and mass flows. The degree of the coupling is also discussed. In the literature such coupling has been formulated incompletely and sometimes in a confusing manner. The reason for this is the lack of a proper combination of LNET theory with the phenomenological theory. The LNET theory involves identifying the conjugated flows and forces …
Nonequilibrium Thermodynamics In Engineering And Science, Y. Demirel
Nonequilibrium Thermodynamics In Engineering And Science, Y. Demirel
YASAR DEMIREL
The field of nonequilibrium thermodynamics has been a popular one outside the United States, especially in Europe, and scientists there from various disciplines have published extensively on the use of nonequilibrium thermodynamics in a large variety of biological, chemical, and mechanical engineering applications. In contrast, the number of publications from North America has been relatively modest. Here, we review the field of nonequilibrium thermodynamics to assess its utility and impact in engineering and science. We find that developments in the fields thermodynamic optimality of processes, dissipative structures, coupled transport and rate processes, and biological systems suggest that in some circumstances …
Phase Stability Analysis Using Interval Newton Method With Nrtl Model, Hatice Gecegormez, Y. Demirel
Phase Stability Analysis Using Interval Newton Method With Nrtl Model, Hatice Gecegormez, Y. Demirel
YASAR DEMIREL
The Gibbs energy minimization using activity coefficient models and nonlinear equation solution techniques are commonly applied for phase stability problems. However, dependence on the initial estimates and multiple solutions for these highly nonlinear equations are common drawbacks for some of the conventional approaches. We have used interval Newton method with the local composition model of NRTL for the phase stability analysis of 10 binary systems and 2 ternary systems at various feed compositions to locate all the stationary points. Results indicate that the interval Newton method is reliable and efficient.
Retrofit Of Distillation Columns Using Thermodynamic Analysis, Y. Demirel
Retrofit Of Distillation Columns Using Thermodynamic Analysis, Y. Demirel
YASAR DEMIREL
Thermodynamic analysis provides the column grand composite curves and exergy loss profiles, which are becoming readily available for a converged distillation column simulation. For example, the Aspen Plus simulator performs the thermodynamic analysis through its Column–Targeting tool for rigorous column calculations. This study uses the column grand composite curves and the exergy loss profiles obtained from Aspen Plus to assess the performance of the existing distillation columns, and reduce the costs of operation by appropriate retrofits in a methanol plant. Effectiveness of the retrofits is also assessed by means of thermodynamics and economics. The methanol plant utilizes two distillation columns …
Non-Isothermal Reaction-Diffusion Systems With Thermodynamically Coupled Heat And Mass Transfer, Y. Demirel
Non-Isothermal Reaction-Diffusion Systems With Thermodynamically Coupled Heat And Mass Transfer, Y. Demirel
YASAR DEMIREL
Non-isothermal reaction-diffusion (RD) systems control the behavior of many transport and rate processes in physical, chemical, and biological systems. A considerable work has been published on mathematically coupled nonlinear differential equations of RD systems by neglecting the possible thermodynamic couplings among heat and mass fluxes, and reaction velocities. Here, the thermodynamic coupling refers that a flux occurs without its primary thermodynamic driving force, which may be gradient of temperature, or chemical potential, or reaction affinity. This study presents the modeling equations of non-isothermal RD systems with coupled heat and mass fluxes excluding the coupling of chemical reactions using the linear …
Nonequilibrium Thermodynamics, 3e Transport And Rate Processes In Physical, Chemical And Biological Systems, Yasar Demirel
Nonequilibrium Thermodynamics, 3e Transport And Rate Processes In Physical, Chemical And Biological Systems, Yasar Demirel
YASAR DEMIREL
Natural phenomena consist of simultaneously occurring transport processes and chemical reactions. These processes may interact with each other and may lead to self-organized structures, fluctuations, instabilities, and evolutionary systems. Nonequilibrium Thermodynamics, 3rd edition emphasizes the unifying role of thermodynamics in analyzing the natural phenomena. This third edition updates and expands on the first and second editions by focusing on the general balance equations for coupled processes of physical, chemical, and biological systems. The new edition contains a new chapter on stochastic approaches to include the statistical thermodynamics, mesoscopic nonequilibrium thermodynamics, fluctuation theory, information theory, and modeling the coupled biochemical systems …
Information In Biological Systems And The Fluctuation Theorem, Yasar Demirel
Information In Biological Systems And The Fluctuation Theorem, Yasar Demirel
YASAR DEMIREL
Some critical trends in information theory, its role in living systems and utilization in fluctuation theory are discussed. The mutual information of thermodynamic coupling is incorporated into the generalized fluctuation theorem by using information theory and nonequilibrium thermodynamics. Thermodynamically coupled dissipative structures in living systems are capable of degrading more energy, and processing complex information through developmental and environmental constraints. The generalized fluctuation theorem can quantify the hysteresis observed in the amount of the irreversible work in nonequilibrium regimes in the presence of information and thermodynamic coupling.
Influence Of Subenvironmental Conditions And Thermodynamic Coupling On A Simple Reaction-Transport Process In Biochemical Systems, Yasar Demirel, R Tevetia
Influence Of Subenvironmental Conditions And Thermodynamic Coupling On A Simple Reaction-Transport Process In Biochemical Systems, Yasar Demirel, R Tevetia
YASAR DEMIREL
Living systems must continuously receive substrates from subenvironment, and the population metabolic rate model is affected on this flow of substrates to be metabolized, its relevant variables, and the rate at which operates. This study focuses on the influences of resistances and bulk phase factors with in the subenvironment and by thermodynamic coupling on reaction-transport processes representing a simple enzymatic conversion of a substrate to a product. Thermodynamic coupling refers to mass flow, or a reaction velocity that occurs without or opposite to the direction imposed by its primary thermodynamic driving force. We considered the effects of (i) subenvironment resistances …
Thermodynamic Analysis, Yasar Demirel
Thermodynamic Analysis, Yasar Demirel
YASAR DEMIREL
This review mainly summarizes some of the developments on the various aspects of thermodynamic analysis within the past 15 years. Therefore, it is limited and will omit some valuable work unintentionally, mainly because of the vast number of publications in the field. The thermodynamic analyses mainly aim at assessing the thermodynamic imperfections and suggest possibleways of improving these imperfections. In this review, thermodynamic analyses have been summarized under thesemethodologies: (i) second law analysis, (ii) exergy analysis, (iii) pinch analysis, (iv) equipartition principle, (v) Gibbs free energy minimization, (vi) thermoeconomics, (vii) exergoeconomics, and (viii) extended exergy analysis. The exergy analysis, which …
Economic Analysis Of Biodiesel And Glycerol Carbonate Production Plant By Glycerolysis, Yasar Demirel, N. Nguyen
Economic Analysis Of Biodiesel And Glycerol Carbonate Production Plant By Glycerolysis, Yasar Demirel, N. Nguyen
YASAR DEMIREL
Techno-economic analysis of an indirect use of carbon dioxide within the route ofglycerolysis of glycerol with urea is investigated. The results show that the net present value of the biodiesel-glycerol carbonate production by glycerolysis is higher than the biodiesel-glycerol carbonate production by direct carboxylationat the end of the 12-year operation with similar capacities. The stochastic model has predicted that using glycerolysis route for the synthesis of glycerol carbonate production may increase the probability of getting positive net present value by about 15%.
Retrofit Of Distillation Columns In Biodiesel Production Plants, Yasar Demirel, N. Nguyen
Retrofit Of Distillation Columns In Biodiesel Production Plants, Yasar Demirel, N. Nguyen
YASAR DEMIREL
Column grand composite curves and the exergy loss profiles produced by the Column-Targeting Tool of the Aspen Plus simulator are used to assess the performance of the existing distillation columns, and reduce the costs of operation by appropriate retrofits in a biodiesel production plant. Effectiveness of the retrofits is assessed by means of thermodynamics and economic improvements. We have considered a biodiesel plant utilizing three distillation columns to purify biodiesel (fatty acid methyl ester) and byproduct glycerol as well as reduce the waste. The assessments of the base case simulation have indicated the need for modifications for the distillation columns. …
Modeling Of Thermodynamically Coupled Reaction-Transport Systems, Yasar Demirel
Modeling Of Thermodynamically Coupled Reaction-Transport Systems, Yasar Demirel
YASAR DEMIREL
Nonisothermal reaction-diffusion systems control the behavior of many transport and rate processes in physical, chemical and biological systems, such as pattern formation and chemical pumps. Considerable work has been published on mathematically coupled nonlinear differential equations by neglecting thermodynamic coupling between a chemical reaction and transport processes of mass and heat. This study presents the modeling of thermodynamically coupled system of a simple elementary chemical reaction with molecular heat and mass transport. The thermodynamic coupling refers that a flow occurs without or against its primary thermodynamic driving force, which may be a gradient of temperature or chemical potential or reaction …
Thermoeconomics Of Seasonal Latent Heat Storage System, Yasar Demirel, H.H Ozturk
Thermoeconomics Of Seasonal Latent Heat Storage System, Yasar Demirel, H.H Ozturk
YASAR DEMIREL
A simple thermoeconomic analysis is performed for a seasonal latent heat storage system for heating a greenhouse. The system consists of three units that are a set of 18 packed-bed solar air heaters, a latent heat storage tank with 6000 kg of technical grade paraffin wax as phase-changing material, and a greenhouse of 180m2. The cost rate balance for the output of a unit is used to estimate the specific cost of exergy for a yearly operation. Based on the cost rate of exergy, fixed capital investment, operating cost, and economic data, approximate cash-flow diagrams have been prepared. The systems …
Non-Isothermal Reaction-Diffusion Systems With Thermodynamically Coupled Heat And Mass Transfer, Yasar Demirel
Non-Isothermal Reaction-Diffusion Systems With Thermodynamically Coupled Heat And Mass Transfer, Yasar Demirel
YASAR DEMIREL
Non-isothermal reaction-diffusion (RD) systems control the behavior of many transport and rate processes in physical, chemical, and biological systems. A considerable work has been published on mathematically coupled nonlinear differential equations of RD systems by neglecting the possible thermodynamic couplings among heat and mass fluxes, and reaction velocities. Here, the thermodynamic coupling refers that a flux occurs without its primary thermodynamic driving force, which may be gradient of temperature, or chemical potential, or reaction affinity. This study presents the modeling equations of non-isothermal RD systems with coupled heat and mass fluxes excluding the coupling of chemical reactions using the linear …
Effective Teaching And Active Learning Of Engineering Courses With Workbook Strategy, Yasar Demirel
Effective Teaching And Active Learning Of Engineering Courses With Workbook Strategy, Yasar Demirel
YASAR DEMIREL
Often mismatches between learning and teaching styles arise because students are in majority visual and sensing learners, and most instructors are intuitive and reflective learners. Beside that, textbooks also have their own styles, and their contents, depth of coverage of materials, and organization may affect the teaching and learning environment. Instructor, as the primary selector of the textbook, has the responsibility in providing students with effective teaching strategy. Here, we present a new strategy called the ‘workbook strategy,” which integrates these four elements: (i) classroom analysis, (ii) use of workbook beside textbook, (iii) group work, and (iv) use of ‘blackboard’ …
Teaching Coupled Transport And Rate Processes, Yasar Demirel
Teaching Coupled Transport And Rate Processes, Yasar Demirel
YASAR DEMIREL
Coupling refers to a flux occurring without its primary thermodynamic driving force; for example, mass flux without a concentration gradient called the thermal diffusion is a well-known coupled process. Coupling also refers to a flux occurring in a direction opposite to the direction imposed by its driving force; for example, a mass flux can occur from a low to a high concentration region and is called the active transport or uphill transport, such as potassium and sodium pumps coupled to chemical energy released by the hydrolysis of adenosine triphosphate (ATP) in biological systems.
Teaching Engineering Courses With Workbooks, Yasar Demirel
Teaching Engineering Courses With Workbooks, Yasar Demirel
YASAR DEMIREL
Society expects that a modern college education will turn out students who are analytical, intellectually curious, culturally aware, employable, and capable of leadership. Some important skills needed for all degree programs are problem solving, communication (written and oral), team or group work, learning, and information processing and technology. Instructors feel rewarded and satisfied when they sense that they have made a difference in the life of a student.
Nonequilibrium Thermodynamics In Engineering And Science, Yasar Demirel, S.I. Sandler
Nonequilibrium Thermodynamics In Engineering And Science, Yasar Demirel, S.I. Sandler
YASAR DEMIREL
The field of nonequilibrium thermodynamics has been a popular one outside the United States, especially in Europe, and scientists there from various disciplines have published extensively on the use of nonequilibrium thermodynamics in a large variety of biological, chemical, and mechanical engineering applications. In contrast, the number of publications from North America has been relatively modest. Here, we review the field of nonequilibrium thermodynamics to assess its utility and impact in engineering and science. We find that developments in the fields thermodynamic optimality of processes, dissipative structures, coupled transport and rate processes, and biological systems suggest that in some circumstances …
Workbook Strategy In Engineering Education, Yasar Demirel
Workbook Strategy In Engineering Education, Yasar Demirel
YASAR DEMIREL
Mismatches between the learning and teaching styles are common because students are in majority visual and sensing learners, yet most instructors are intuitive and reflective learners. Beside that, textbooks also have their own styles, and their contents, depth of coverage of materials, and organization may affect the teaching and learning. For reducing the mismatches, and achieving effective teaching and active learning, we present ‘workbook strategy,” which integrates the following four elements: (i) classroom analysis, (ii) use of workbook beside textbook, (iii) group work, and (iv) use of ‘blackboard’ as information technology. The workbook strategy provides all the essential verbal and …
Thermodynamics And Bioenergetics, Yasar Demirel
Thermodynamics And Bioenergetics, Yasar Demirel
YASAR DEMIREL
Bioenergetics is concerned with the energy conservation and conversion processes in a living cell, particularly in the inner membrane of the mitochondrion. This review summarizes the role of thermodynamics in understanding the coupling between the chemical reactions and the transport of substances in bioenergetics. Thermodynamics has the advantages of identifying possible pathways, providing a measure of the efficiency of energy conversion, and of the coupling between various processes without requiring a detailed knowledge of the underlying mechanisms. In the last five decades, various new approaches in thermodynamics, non-equilibrium thermodynamics and network thermodynamics have been developed to understand the transport and …
Thermodynamic Analysis Of Convective Heat Transfer In An Annular Packed Bed, Yasar Demirel, R Kahraman
Thermodynamic Analysis Of Convective Heat Transfer In An Annular Packed Bed, Yasar Demirel, R Kahraman
YASAR DEMIREL
A combination of the first and second law of thermodynamics has been utilized in analyzing the convective heat transfer in an annular packed bed. The bed was heated asymmetrically by constant heat fluxes. Introduction of the packing enhances wall to fluid heat transfer considerably, hence reduces the entropy generation due to heat transfer across a finite temperature difference.
On The Effective Heat Transfer Parameters In A Packed Bed, Yasar Demirel, R.N. Sharma, H.H. Ali
On The Effective Heat Transfer Parameters In A Packed Bed, Yasar Demirel, R.N. Sharma, H.H. Ali
YASAR DEMIREL
Heat transfer behavior of fluid flow through packed tube and channel has an important impact on the de- sign and operation of catalytic reactors.
Thermodynamic Analysis Of Thermomechanical Coupling Incouette Flow, Yasar Demirel
Thermodynamic Analysis Of Thermomechanical Coupling Incouette Flow, Yasar Demirel
YASAR DEMIREL
Couette ¯ow provides the simplest model for the analysis of heat transfer for ¯ow between parallel plates and between two coaxial cylinders. Design of such devices with the consideration of the thermo- mechanical coupling of viscous heat generation and Couette ¯ow is important since they are used in lubri- cation, polymer and food processing, and viscometry.
Entropy Generation In A Rectangular Packed Duct With Wall Heat Flux, Yasar Demirel, R. Kahraman
Entropy Generation In A Rectangular Packed Duct With Wall Heat Flux, Yasar Demirel, R. Kahraman
YASAR DEMIREL
The entropy generation due to heat transfer and friction has been calculated for fully developed, forced convection flow in a large rectangular duct. packed with spherical particles, with constant heat fluxes applied to both the top (heated) and bottom (cooled) wall. An approximate analytical expression for the velocity profile developed for packed bed with H/dp > 5 has been used together \vith the energy equation of fully developed flow to calculate the nonisothermal temperature profiles along the flow passage. The velocity prolile takes into account the increase in the velocity near the wall due to the higher voidage in this region …
Estimation Of The Entropy Of Vaporization At The Normal, Yasar Demirel
Estimation Of The Entropy Of Vaporization At The Normal, Yasar Demirel
YASAR DEMIREL
The entropy of vaporization at the normal boiling point has been estimated for binary and ternary azotropic mixtures containing water, alcohol or acetic acid. For this purpose, the Lee±Kesler correlation, developed originally for pure substances, is used with the appropriate mixing rules to estimate the heat of vaporization of the mixtures. Estimations for the entropy of vaporization of the 97 binary and 78 ternary mixtures are expressed as function of the ratio of the normal boiling point to average molecular weight. These expressions predict the entropy of vaporization satisfactorily, with less than 5% average deviation
Entropy Generation In A Rectangular Packed Duct With Wall, Yasar Demirel, R. Kahraman
Entropy Generation In A Rectangular Packed Duct With Wall, Yasar Demirel, R. Kahraman
YASAR DEMIREL
The entropy generation due to heat transfer and friction has been calculated for fully developed forced convection flow in a large rectangular duct packed with spherical particles with constant heat fluxes applied to both the top heated and bottom cooled wall.
Packing Size Anetric Heating, Yasar Demirel, B.A. Abu Al-Saud, H.H. Ali, Y. Makkawi
Packing Size Anetric Heating, Yasar Demirel, B.A. Abu Al-Saud, H.H. Ali, Y. Makkawi
YASAR DEMIREL
An experimental and numerical investigation of fully developed forced convection in large rectangular packed ducts is presented. The horizontally oriented ducts have the length-to-separation distance ratio of L/H=16 with two aspect ratios of W/H=8 and 4. A constant heat flux is supplied to the top wall, while the bottom and side walls are insulated. Packing of hard polyvinyl chloride Raschig rings with outside diameters of 48 and 34 mm, and expanded polystyrene spheres with diameters of 48, 38 and 29 mm are used in the air flow passage. The pressure drop, the heat flux, axial and transverse temperature profiles of …
Enhancement Of Convection Heat-Transfer, Yasar Demirel, H.H. Al-Ali, B.A. Abu-Al-Saud
Enhancement Of Convection Heat-Transfer, Yasar Demirel, H.H. Al-Ali, B.A. Abu-Al-Saud
YASAR DEMIREL
Characteristics of wall-to-air heat transfer for a fully developed forced convection have been studied in a large rectangular packed duct with 160 cm heated length, 40 cm width, and for low bed equivalent diameter to particle diameter ratio. The separation distance between the top and bottom walls is 10 cm. A uniform heat ¯ux is supplied at the top wall, while the bottom wall is insulated. Raschig rings in two and spherical packing in three sizes have been used in the air ¯ow passage to investigate the enhancement of heat transfer due to packing. Temperature pro®les for the steady and …
Irreversibility Profiles In A Circular Couette Flow Of Temperature Dependent Materials, Yasar Demirel
Irreversibility Profiles In A Circular Couette Flow Of Temperature Dependent Materials, Yasar Demirel
YASAR DEMIREL
The irreversibility distributions have been calculated for a circular Couette flow of ethylene glycol with temperature dependent thermal conductivity and viscosity. The approximate series solutions of velocity and temperature fields are used to obtain the gradients to calculate the spatial entropy generation rate with narrowing gap of the Couette. It was found that the irreversibility distribution is relatively more uniform for a narrow-gap Couette.
Numerical Analysis Of Convection Heat Transfer In A Rectangular Packed Duct Withasymmetric Heating, Yasar Demirel, Y. Makkawi, H.H. Ali
Numerical Analysis Of Convection Heat Transfer In A Rectangular Packed Duct Withasymmetric Heating, Yasar Demirel, Y. Makkawi, H.H. Ali
YASAR DEMIREL
Fully developed, forced convection heat transfer in a rectangular packed duct is analyzed numerically based on a two-dimensional model incorporating the effects of Raschig ring packing on the Ergun equation. The boundary conditions are based on asymmetric heating with only the top wall supplied with a constant heat flux, while the other walls are adiabatic. The numerical predictions are compared with measured temperature profiles and local Nusselt numbers obtained from a large scale packed duct with L/H = 16 and W/H = 8, using Raschig rings of 4.8 cm in size. The prediction represents the experimental data satisfactorily. The volumetric …