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This study explores the effect of silver nanoparticles on heat transfer and flow behavior within the context of the Ellis fluid model. It specifically considers electroosmotic forces in a nonuniform divergent channel with compliant walls. The analysis involves studying thermal transport in silver-blood nanofluid flow, using MATHEMATICA 13.2 software to obtain exact solutions for velocity and temperature distribution. Findings reveal that certain parameters, such as wall damping and wall elastic properties, increase skin friction, while compliant wall parameters generally reduce flow velocity. Additionally, wall rigidity and tension parameters lead to larger trapped boluses. Notably, a 1% concentration of nanoparticles enhances heat transfer by up to 13.75%, offering control over heat transfer rates. This research introduces a novel perspective by examining compliant wall impacts on heat transfer analysis in the context of electroosmotic flow within the Ellis fluid model, incorporating silver nanoparticles with potential therapeutic applications due to their antibacterial properties.

This study explores the effect of silver nanoparticles on heat transfer and flow behavior within the context of the Ellis fluid model. It specifically considers electroosmotic forces in a nonuniform divergent channel with compliant walls. The analysis involves studying thermal transport in silver-blood nanofluid flow, using MATHEMATICA 13.2 software to obtain exact solutions for velocity and temperature distribution. Findings reveal that certain parameters, such as wall damping and wall elastic properties, increase skin friction, while compliant wall parameters generally reduce flow velocity. Additionally, wall rigidity and tension parameters lead to larger trapped boluses. Notably, a 1% concentration of nanoparticles enhances heat transfer by up to 13.75%, offering control over heat transfer rates. This research introduces a novel perspective by examining compliant wall impacts on heat transfer analysis in the context of electroosmotic flow within the Ellis fluid model, incorporating silver nanoparticles with potential therapeutic applications due to their antibacterial properties. [ABSTRACT FROM AUTHOR]

Background: The essential features of nanoparticles in nanofluids play a vital role in nanotechnology. The nanosized particles of carbon are known as carbon nanotubes (CNTs). The properties of CNT like thermal and electrical conductivity, lightweight, flexibility, and mechanical strength support its applications in the medical field i.e., diagnostic and therapeutic agents (drugs, antibodies, biosensors, vaccines etc.). These are not only excellent vehicles for drug delivery and gene therapies but also useful in biosensor diagnostic, enantiomer separation of chiral drugs, tissue regeneration, extraction, and analysis of pollutants and drugs. Objective: The focus of this research work is to open the essential features of peristaltic transport of Ellis nanofluid through uniform and non-uniform channels with suspension of single-walled carbon nanotubes (SWCNT). The consideration of blood flow with SWCNT under the effects of heat generation and electroosmosis is one of the key factors of this investigation. Method: The complexity of the system is reduced with the implementation of the concepts of longer wavelength and lower Reynolds number. The governing two-dimensional equations are simplified by introducing dimensionless variables and parameters. The mathematical tool “MATHEMATICA 13.3” is used to compute the exact solution and graphical demonstration of velocity, temperature, heat transfer rate, and streamlines. Computational results: It is noticed that velocity, temperature, and heat transfer rate are prominent in non-uniform channels as compared to uniform channels. Similarly, the size and number of boluses during the trapping phenomenon increase or decrease quickly in non-uniform channels. The volumetric addition of SWCNT diminishes the velocity and temperature while the heat transfer rate is enhanced in both channels but in the nonuniform channel effects are more prominent. Applications: This study explores the applications of SWCNT in medical fields like angiography, angioplasty, and cancer therapy. Novelty: The present study is new and has never been addressed before.

The current study aims to investigate the effect of partial slip conditions over double diffusion convection. The phenomenon is applied with the inclined magnetic flux of peristaltic flow on Ellis nanofluid model in an asymmetric channel. The fundamental differential equations are constructed and solved through lubrication approximation that gives the coupled system of ordinary differential equations. This resultant system is further solved numerically, and graphic representation are used to physically comprehend the flow quantity data. The whole procedure is carried out under the trapping mechanism by drawing contour streamlines. The knowledge gained from this work will be useful in the creation of intelligent magneto-peristaltic pumps for specific heat and medication delivery phenomena.

The present work analyzes the thermal instability of mixed convection in a horizontal porous channel that is saturated by a shear-thinning fluid following Ellis' rheology. The fluid layer is heated from below by a constant heat flux and cooled from above by the same heat flux. The instability of such a system is investigated by means of a small-disturbances analysis and the resulting eigenvalue problem is solved numerically by means of a shooting method. It is demonstrated that the most unstable modes on the instability threshold are those with infinite wavelength and an analytical expression for such conditions is derived from an asymptotic analysis. Results show that the non-Newtonian character of the fluid has a destabilizing role. [ABSTRACT FROM AUTHOR]

The in vitro fabrication of big osteoarticular implants integrating biomaterials and cells is of tremendous interest because these tissues have a limited ability to regenerate. However, the growth of such cells in vitro is highly problematic, especially later in the culture, when the extracellular matrix has almost filled the initial porous network. Thus, the fluid flow required to properly perfuse the sample cannot be obtained by the hydraulic driving force alone. Fluid pumping is a central concern of a microfluidic system and electro-osmotic pumps (EOPs) are commonly employed for this purpose. Using electro-kinetic equations as a basis, this study analyzed the variations of a two-fluid electro-osmotic flow of viscoelastic fluid flow through a channel. The behavior of the fluid was studied through the Ellis equation. This is how the electro-osmotic pump functions, as demonstrated in the literature that it electrically drags a conducting fluid across a non-conducting fluid through interfacial dragging force along the channel. A steady-state analytical solution for the system in a conducting fluid channel was studied by undertaking an interface planner for fluids exhibiting Newtonian rheological properties. The pumping characteristics were studied in detail by using the Ellis model's parameters. The fluid rheology was studied, which showed the viability of this technique. [ABSTRACT FROM AUTHOR]

This study aims to describe the information-seeking behavior of students in the Library and Information Science Study Program when searching for information. This research is quantitative research with a descriptive method. The population in this study were library and information science students, totaling 288 people, with a sample of 75 people. Sampling was determined based on the simple random sampling technique, which is a random sampling technique without regard to the existing strata in the population. The dataset for this study was obtained through the distribution of questionnaires. Data analysis was carried out descriptively with the formula for calculating relative frequency and percentage. Based on the results of the study, it can be concluded that the information-seeking behavior of students of the Library and Information Science Study Program in searching for information as a whole is positive. These results are known from the average score obtained, which is 2.92. This score is on an interval scale of 2.52–3.27. [ABSTRACT FROM AUTHOR]

The present work analyzes the thermal instability of mixed convection in a horizontal porous channel that is saturated by a shear-thinning fluid following Ellis’ rheology. The fluid layer is heated from below by a constant heat flux and cooled from above by the same heat flux. The instability of such a system is investigated by means of a small-disturbances analysis and the resulting eigenvalue problem is solved numerically by means of a shooting method. It is demonstrated that the most unstable modes on the instability threshold are those with infinite wavelength and an analytical expression for such conditions is derived from an asymptotic analysis. Results show that the non-Newtonian character of the fluid has a destabilizing role.

The Ellis model describes the apparent viscosity of a shear–thinning fluid with no singularity in the limit of a vanishingly small shear stress. In particular, this model matches the Newtonian behaviour when the shear stresses are very small. The emergence of the Rayleigh–Bénard instability is studied when a horizontal pressure gradient, yielding a basic throughflow, is prescribed in a horizontal porous layer. The threshold conditions for the linear instability of this system are obtained both analytically and numerically. In the case of a negligible flow rate, the onset of the instability occurs for the same parametric conditions reported in the literature for a Newtonian fluid saturating a porous medium. On the other hand, when high flow rates are considered, a negligibly small temperature difference imposed across the horizontal boundaries is sufficient to trigger the convective instability. [ABSTRACT FROM AUTHOR]

This paper aims to survey the method of Selecting subject to coping with Information Resources based on the Ellis model in Seminary base on new media, study 323 Students in Fars and Bushehr Province. The method of this study is a survey with analytical approach. Data collection tools in this study was questionnaire and in order to assess validity (content), and the questionnaire reliability was obtained by Cronbach alpha. Sampling is purposeful; Descriptive and analytical statistical methods such as Spearman's correlation coefficient, Kruskal-Wallis and Friedman tests were utilized. prying mind (2/6), reviewing of information resources (3/13), Sites in the Internet related to subjects or social networks (3/92), Using online databases or weblogs (3/48), Authority (3/7), Studying abstract (2/48), is so important for seminary students. The results showed that Students of Seminary selected different methods base on new media that selected by research population for Selecting subject to coping with Information Resources and its not based on the Ellis Model.

The evaluation of the accuracy of the Ostwald–de Waele model in solving the Graetz–Nusselt problem is made by comparing with the standard solution for the Ellis liquid. As a result of the analysis, it is shown that the problem solution constructed on the exponential equation leads to substantial distortions of the heat transfer pattern. [ABSTRACT FROM AUTHOR]

Highlights • This paper presents a methodology to infer the rheology of a fluid from free surface velocity measurement. • Rheology is reconstructed by minimizing the difference between simulated and measured data. • The method is tested on synthetic and real experimental data for the dam-break flow problem. • Particle Tracking Velocimetry is used to measure the free surface velocity. • Models based on the Navier–Stokes equations and the lubrication approximation with an Ellis rheology are presented. Abstract This study presents a new rheometry technique which requires a free surface velocity field as an input. By minimising the difference between observed and simulated data, we show here that it is possible to estimate the three parameters of an assumed Ellis rheological law. The dam-break problem is considered here with molasses as the working fluid. The free surface velocity is evaluated by seeding the free surface with buoyant particles and using particle tracking velocimetry. The parameter identification is successfully tested with "synthetic" data produced by the numerical model. The parameter identification algorithm is shown to be robust even when significant noise is added to the synthetic dataset. For true experimental data, the reconstructed flow curve is within 25% of the actual one, demonstrating the potential of the method for circumstances where standard rheometry does not apply. [ABSTRACT FROM AUTHOR]

The determination of temperature and auxiliary quantities such as local and average Nusselt numbers for thermally developing flow is referred as the Graetz problem. In the classical Graetz problem, the fluid entering the tube or channel is Newtonian in nature. Here, an extension of the classical Graetz problem is presented by assuming that the fluid entering the tube or channel obeys the Ellis constitutive equation. The energy equation for the considered problem is solved using the separation of variables technique supplemented with the MATLAB routine bvp4c for computation of the eigenvalues and numerical solution of the associated Sturm-Liouville boundary value problem. The problem is solved for two types of thermal boundary conditions, namely, uniform surface temperature and uniform surface heat flux for both flat and circular geometries. Expressions for bulk mean temperature and local and average Nusselt numbers are presented and discussed through tables and graphs. [ABSTRACT FROM AUTHOR]

The accuracy of the Ostwald-de Waele model in solving the problem of roll flow has been assessed by comparing with the "reference" solution for an Ellis fluid. As a result of the analysis, it has been shown that the model based on a power-law equation leads to substantial distortions of the flow pattern. [ABSTRACT FROM AUTHOR]

In the paper the influence of bearing surfaces roughness on the pressure distribution and load-carrying capacity of a thrust bearing is discussed. The equations of motion of an Ellis pseudo-plastic fluid are used to derive the Reynolds equation. After general considerations on the flow in a bearing clearance and using the Christensen theory of hydrodynamic rough lubrication the modified Reynolds equation is obtained. The analytical solutions of this equation for the cases of a squeeze film bearing and an externally pressurized bearing are presented. As a result one obtains the formulae expressing pressure distribution and load-carrying capacity. A thrust radial bearing is considered as a numerical example.

The goal of this study is to evaluate the compatibility between Iranian digital libraries user interface and the elements of Ellis model of information seeking behavior. This study was performed using evaluation method with a checklist. This list is based on six features of Ellis model, "Starting", "Chaining", "Browsing", "Differentiating", "Monitoring" and "Extracting" and included 110 sub-components that have been developed using Delphi method. The population of this study included 5 library softwares: Azarakhsh, Simorgh, Papyrus, Payam and Parvan. Results showed that the average of scores of user interface of softwares is as follows: in Starting 99.6, Chaining 117.2, Browsing 29.6, Differentiating 53. 2, Monitoring 22.4 and Extracting 39. Among the softwares of digital libraries, according to the total score for elements of Ellis model (1080), Azarakhsh with 549 points is in the first rank and had the highest support for elements of Ellis model. It also became clear that Chaining with 586 points (%55) had the highest support in softwares of digital libraries. Also the elements of Chaining, Starting and Differentiating earned sequently the highest rank in softwares of digital libraries. Finally, testing research hypotheses with %95 confidence showed that among softwares of digital libraries there is no significant difference regarding the rate of support of elements of information seeking behavior of Ellis model.

Graphic User interface serves as a bridge between man and databases. Its primary purpose is to assist uses by establishing interaction with computer systems. Database user interface designers have seldom focused on the impact of user information seeking behaviors on the database user interface structures. Therefore, it is crucial to incorporate the user information seeking behavior within database software design as well as analyzing their impact on upgrade and optimization of user interface environment. The present study intends to determine the degree of correspondence of database interface with information seeking behavioral components of Ellis’ model. The component studied starting, chaining, browsing, differentiating, monitoring and extracting. Investigators employed direct observation method, using a checklist, in order to see how much the database interfaces support these components. Results indicated that the information seeking behavior components outlined by Ellis Model are not fully considered in database user interface design. Some of the components such as starting, chaining and differentiation were to some extent supported by some of database user interfaces studied. However elements such as browsing, monitoring and extracting have not been incorporated within the user interface structures of these databases. On the whole, the degree of correspondence and correlation of database user interfaces with Ellis information seeking components is about average. Therefore incorporating these elements in design and evaluation of user interface environment could have high impact on better optimization of database interface environment and consequently the very process of search and retrieval.

• Constitutive relation for Ellis fluid is employed. • Induced magnetic field is taken into account. • Nanofluid model consists of Brownian motion and thermophoresis. • Non-unifrom channel is assumed for flow analysis. The present research explores the wave of peristalsis on magneto Ellis nanofluids within non-uniform channel by using Dufour and Soret parameters. The mathematical representation of the magneto Ellis nanofluids having double diffusion convection under magnetic flux is presented in detail. The nonlinear partial differential equations are simplified by applying long wavelength and lesser Reynolds number. The resultant differential equations are further simplified numerically, and exact solutions of concentration, temperature, and nanoparticle fraction are computed. Further, the significance of numerous material constraints of flow quantities is depicted through graphs. It is revealed that the huge value of Brownian motion and Soret number decreases the concentration of nanosolid particle. Solid nanoparticles in a nanofluid during micro-mixing procedure collide randomly hence transferring the molecular energy into thermal energy that triggers the rise in temperature. [ABSTRACT FROM AUTHOR]

Apparent viscosities of CO-in-water foams were measured in a wide range of shear rate from 50 to 105 inverse second for enhanced oil recovery (EOR) application. The CO-in-water dispersions, made of 50:50 weight proportions of CO and water with 1 wt.% surfactant concentration, were prepared in high-pressure recirculation apparatus under pressure where CO density becomes 0.7, 0.8, and 0.9 g/mL at each temperature of 35, 45, and 55°C. The surfactants used for the foam generation were sodium dodecyl polypropoxy sulfates with average propoxylation degrees of 4.7 and 6.2. The foam viscosity showed shear thinning behaviors with power-law indices ranging from 0.80 to 0.85, and approached a Newtonian regime in the lower shear rate range at several tens of inverse second. Zero-shear viscosity values projected from experimental data based on Ellis model were as high as 57.4 mPa·s and enough to control the mobility of water and CO in oil reservoirs. [ABSTRACT FROM AUTHOR]

The goal of this study is to evaluate the compatibility between Iranian digital libraries user interface and the elements of Ellis model of information seeking behavior. The study was performed using evaluation method with a checklist. The checklist is based on six features of Ellis model, "Starting", "Chaining", "Browsing", "Differentiating", "Monitoring" and "Extracting" including 110 subcomponents developed by using Delphi method. The population of the study included 5 library softwares, namely Azarakhsh, Simorgh, Papyrus, Payam and Parvan. Results showed that the average scores of user interface of softwares are as follows: as for Starting 99.6, Chaining 117.2, Browsing 29.6, Differentiating 53.2, Monitoring 22.4 and Extracting 39. Among the softwares, according to the total score for elements of Ellis model (1080), Azarakhsh with 549 points was in the first rank and had the highest support for elements of Ellis model. It also became clear that Chaining with 586 points (55%) had the highest support in softwares of digital libraries. Also the elements of Chaining, Starting and Differentiating earned the highest rank in sequence among the digital libraries softwares. Finally, testing research hypotheses showed with 95% confidence that among the softwares of digital libraries there is no significant difference regarding the rate of support of elements of information seeking behavior of Ellis model. [ABSTRACT FROM AUTHOR]

Abstract: The steady and non-steady flows of a liquid polymer treated as a non-Newtonian fluid on the inner surface of a horizontal rotating cylinder are investigated. Since the Reynolds number is small and the liquid film is thin, a simple lubrication approximation is applied. Governing equations for non-steady Power-Law and Ellis fluids are solved numerically and the time of transition from non-steady to steady-state mode for various model parameters and flow conditions are defined. The stabilization effect of a chemical reaction within the polymeric fluid (reactive flow) is examined. [Copyright &y& Elsevier]

Abstract: The formation of a thin film by (i) the slow penetration of a gas bubble into a liquid filled tube, (ii) the withdrawal of a planar substrate from a liquid filled gap, is investigated theoretically for the cases of both Newtonian and shear-thinning liquids; the latter conforming to either a power–law or Ellis model. Formulated as a boundary value problem underpinned by lubrication theory, the analysis gives rise to a system of ordinary differential equations which are solved numerically subject to appropriate boundary conditions. For Newtonian liquids comparison of the predicted residual film thickness for a wide range of capillary number, Ca ∈(10−4, 10), is made with others obtained using existing expressions, including the classical one of Bretherton, in the region of parameter space over which they apply. In the case of (i), prediction of the behaviour of the residual fluid fraction and gap-to-film thickness ratio, for a Newtonian liquid and one that is shear-thinning and modelled via a power–law, is found to be in particularly good agreement with experimental data for Ca <0.2. For (ii), both shear-thinning models are utilized and contour plots of residual film thickness generated as a function of Ca and the defining parameters characteristic of each model. [Copyright &y& Elsevier]

Rimming flow on the inner surface of a horizontal rotating cylinder is investigated. Using a scale analysis, a theoretical description is obtained for steady-state non-Newtonian flow. Simple lubrication theory is applied since the Reynolds number is small and the liquid film is thin. Since the Deborah number is very small the flow is viscometric. The shear-thinning number, which characterizes the shear-thinning effect, may be small or large. A general constitutive law for this kind of flow requires only a single function relating shear stress and shear rate that corresponds to a generalized Newtonian liquid. For this case the run-off condition for rimming flow is derived. Provided the run-off condition is satisfied, the existence of a continuous steady-state solution is proved. The rheological models, which show Newtonian behavior at low shear rates with transition to power-law shear thinning at moderate shear rates, are considered. Numerical results are carried out for the Carreau and Ellis models, which exhibit Newtonian behavior near the free surface and power-law behavior near the wall of the rotating cylinder. [Copyright &y& Elsevier]

The rheology of PP filled with three different types of fillers, namely synthetic sodium aluminium silicate (SSAS), aluminium silicate (AS) and calcium carbonate (CaCO3), at concentrations up to 40% was studied. Variation of shear and extensional viscosity was evaluated for all the compositions. When filler loading was less than 20%, the shear viscosity at low shear rates was less than that of virgin PP. Flow curves are described by the Ellis model. The onset of non-Newtonian shear thinning behaviour is related to parameter η10/τ1/2. Although fillers are white, they imparted a yellowish tone at lower loadings. At higher loadings, this yellowing effect was masked, yielding a lower yellowness index. [ABSTRACT FROM AUTHOR]

The drag coefficient for bubbles with mobile or immobile interface rising in shear-thinning elastic fluids described by an Ellis or a Carreau model is discussed. Approximate solutions based on linearization of the equations of motion are presented for the highly elastic region of flow. These solutions are in reasonably good agreement with the theoretical predictions based on variational principles and with published experimental data. [ABSTRACT FROM AUTHOR]

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