Similarity solution of axisymmetric non-Newtonian wall jets with swirl
Czech Academy of Sciences Publication Activity Database
Kolář, Václav
2011-01-01
Roč. 12, č. 6 (2011), s. 3413-3420 ISSN 1468-1218 R&D Projects: GA AV ČR IAA200600801 Institutional research plan: CEZ:AV0Z20600510 Keywords : similarity solution * wall jets * non-Newtonian fluids * power-law fluids * swirl Subject RIV: BK - Fluid Dynamics Impact factor: 2.043, year: 2011
Turbulent structures of non-Newtonian solutions containing rigid polymers
Mohammadtabar, M.; Sanders, R. S.; Ghaemi, S.
2017-10-01
The turbulent structure of a channel flow of Xanthan Gum (XG) polymer solution is experimentally investigated and compared with water flow at a Reynolds number of Re = 7200 (based on channel height and properties of water) and Reτ = 220 (based on channel height and friction velocity, uτ0). The polymer concentration is varied from 75, 100, and 125 ppm to reach the point of maximum drag reduction (MDR). Measurements are carried out using high-resolution, two-component Particle Image Velocimetry (PIV) to capture the inner and outer layer turbulence. The measurements showed that the logarithmic layer shifts away from the wall with increasing polymer concentration. The slopes of the mean velocity profile for flows containing 100 and 125 ppm XG are greater than that measured for XG at 75 ppm, which is parallel with the slope obtained for deionized water. The increase in slope results in thickening buffer layer. At MDR, the streamwise Reynolds stresses are as large as those of the Newtonian flow while the wall-normal Reynolds stresses and Reynolds shear stresses are significantly attenuated. The sweep-dominated region in the immediate vicinity of the wall extends further from the wall with increasing polymer concentration. The near-wall skewness intensifies towards positive streamwise fluctuations and covers a larger wall-normal length at larger drag reduction values. The quadrant analysis at y + 0 = 25 shows that the addition of polymers inclines the principal axis of v versus u plot to almost zero (horizontal) as the joint probability density function of fluctuations becomes symmetric with respect to the u axis at MDR. The reduction of turbulence production is mainly associated with the attenuation of the ejection motions. The spatial-correlation of the fluctuating velocity field shows that increasing the polymer concentration increases the spatial coherence of u fluctuations in the streamwise direction while they appear to have the opposite effect in the wall
On multiple solutions of non-Newtonian Carreau fluid flow over an inclined shrinking sheet
Khan, Masood; Sardar, Humara; Gulzar, M. Mudassar; Alshomrani, Ali Saleh
2018-03-01
This paper presents the multiple solutions of a non-Newtonian Carreau fluid flow over a nonlinear inclined shrinking surface in presence of infinite shear rate viscosity. The governing boundary layer equations are derived for the Carreau fluid with infinite shear rate viscosity. The suitable transformations are employed to alter the leading partial differential equations to a set of ordinary differential equations. The consequential non-linear ODEs are solved numerically by an active numerical approach namely Runge-Kutta Fehlberg fourth-fifth order method accompanied by shooting technique. Multiple solutions are presented graphically and results are shown for various physical parameters. It is important to state that the velocity and momentum boundary layer thickness reduce with increasing viscosity ratio parameter in shear thickening fluid while opposite trend is observed for shear thinning fluid. Another important observation is that the wall shear stress is significantly decreased by the viscosity ratio parameter β∗ for the first solution and opposite trend is observed for the second solution.
Numerical solution of chemically reactive non-Newtonian fluid flow: Dual stratification
Rehman, Khalil Ur; Malik, M. Y.; Khan, Abid Ali; Zehra, Iffat; Zahri, Mostafa; Tahir, M.
2017-12-01
We have found that only a few attempts are available in the literature relatively to the tangent hyperbolic fluid flow induced by stretching cylindrical surfaces. In particular, temperature and concentration stratification effects have not been investigated until now with respect to the tangent hyperbolic fluid model. Therefore, we have considered the tangent hyperbolic fluid flow induced by an acutely inclined cylindrical surface in the presence of both temperature and concentration stratification effects. To be more specific, the fluid flow is attained with the no slip condition, which implies that the bulk motion of the fluid particles is the same as the stretching velocity of a cylindrical surface. Additionally, the flow field situation is manifested with heat generation, mixed convection and chemical reaction effects. The flow partial differential equations give a complete description of the present problem. Therefore, to trace out the solution, a set of suitable transformations is introduced to convert these equations into ordinary differential equations. In addition, a self-coded computational algorithm is executed to inspect the numerical solution of these reduced equations. The effect logs of the involved parameters are provided graphically. Furthermore, the variations of the physical quantities are examined and given with the aid of tables. It is observed that the fluid temperature is a decreasing function of the thermal stratification parameter and a similar trend is noticed for the concentration via the solutal stratification parameter.
Directory of Open Access Journals (Sweden)
M.J. Uddin
2016-09-01
Full Text Available The two-dimensional unsteady laminar free convective heat and mass transfer fluid flow of a non-Newtonian fluid adjacent to a vertical plate has been analyzed numerically. The two parameters Lie group transformation method that transforms the three independent variables into a single variable is used to transform the continuity, the momentum, the energy and the concentration equations into a set of coupled similarity equations. The transformed equations have been solved by the Runge–Kutta–Fehlberg fourth-fifth order numerical method with shooting technique. Numerical calculations were carried out for the various parameters entering into the problem. The dimensionless velocity, temperature and concentration profiles were shown graphically and the skin friction, heat and mass transfer rates were given in tables. It is found that friction factor and heat transfer (mass transfer rate for methanol are higher (lower than those of hydrogen and water vapor. Friction factor decreases while heat and mass transfer rate increase as the Prandtl number increases. Friction (heat and mass transfer rate factor of Newtonian fluid is higher (lower than the dilatant fluid.
Non Newtonian gravity creeping flow
International Nuclear Information System (INIS)
Gratton, J.; Mahajan, S.M.; Minotti, F.
1988-11-01
We derive the governing equations for creeping gravity currents of non Newtonian liquids having a power law rheology, using a lubrication approximation. We consider unidirectional and axisymmetric currents. The equations differ from those for Newtonian liquids, being nonlinear in the spatial derivative of the thickness of the current. However, many solutions are closely analogous to those for Newtonian rheology; in particular the spreading relations can also be expressed as power laws of time, with exponents that depend on the rheological index. Similarity solutions for currents whose volume varies as a power of time are obtained. For the spread of a constant volume of liquid, analytic solutions are found. We also derive solutions of the waiting-time type, as well as the ones describing steady flows from a constant source to a sink. General travelling wave solutions are given, and analytic formulae for a simple case are derived. A phase plane formalism, that allows the systematic derivation of self similar solutions, is introduced. The application of the Boltzmann transform is briefly discussed. Present results are closely analogous to those for Newtonian liquids; all the solutions obtained here have their counterparts in Newtonian flows. This happens because the power law rheology, like the Newtonian constitutive relation, involves a single dimensional parameter. Thus one finds similarity solutions whenever the analogous Newtonian problem is self similar. Although the spreading relations are rheology-dependent, in most cases the dependence is rather weak. The present results may be of interest for geophysics since the lithosphere deforms according to an average power law rheology. (author). 17 refs
Structural Optimization of non-Newtonian Microfluidics
DEFF Research Database (Denmark)
Jensen, Kristian Ejlebjærg; Okkels, Fridolin
2011-01-01
We present results for topology optimization of a non-Newtonian rectifier described with a differential constitutive model. The results are novel in the sense that a differential constitutive model has not been combined with topology optimization previously. We find that it is necessary to apply...... optimization of fluids. We test the method on a microfluidic rectifier and find solutions topologically different from experimentally realized designs....
Non-Newtonian fluid flow in 2D fracture networks
Zou, L.; Håkansson, U.; Cvetkovic, V.
2017-12-01
Modeling of non-Newtonian fluid (e.g., drilling fluids and cement grouts) flow in fractured rocks is of interest in many geophysical and industrial practices, such as drilling operations, enhanced oil recovery and rock grouting. In fractured rock masses, the flow paths are dominated by fractures, which are often represented as discrete fracture networks (DFN). In the literature, many studies have been devoted to Newtonian fluid (e.g., groundwater) flow in fractured rock using the DFN concept, but few works are dedicated to non-Newtonian fluids.In this study, a generalized flow equation for common non-Newtonian fluids (such as Bingham, power-law and Herschel-Bulkley) in a single fracture is obtained from the analytical solutions for non-Newtonian fluid discharge between smooth parallel plates. Using Monte Carlo sampling based on site characterization data for the distribution of geometrical features (e.g., density, length, aperture and orientations) in crystalline fractured rock, a two dimensional (2D) DFN model is constructed for generic flow simulations. Due to complex properties of non-Newtonian fluids, the relationship between fluid discharge and the pressure gradient is nonlinear. A Galerkin finite element method solver is developed to iteratively solve the obtained nonlinear governing equations for the 2D DFN model. Using DFN realizations, simulation results for different geometrical distributions of the fracture network and different non-Newtonian fluid properties are presented to illustrate the spatial discharge distributions. The impact of geometrical structures and the fluid properties on the non-Newtonian fluid flow in 2D DFN is examined statistically. The results generally show that modeling non-Newtonian fluid flow in fractured rock as a DFN is feasible, and that the discharge distribution may be significantly affected by the geometrical structures as well as by the fluid constitutive properties.
Czech Academy of Sciences Publication Activity Database
Hundertmark-Zaušková, A.; Lukáčová-Medviďová, M.; Nečasová, Šárka
2016-01-01
Roč. 68, č. 1 (2016), s. 193-243 ISSN 0025-5645 R&D Projects: GA ČR(CZ) GAP201/11/1304 Institutional support: RVO:67985840 Keywords : non-Newtonian fluids * fluid-structure interaction * shear-thinning fluids Subject RIV: BA - General Mathematics Impact factor: 0.592, year: 2016 http://projecteuclid.org/euclid.jmsj/1453731541
On preconditioning incompressible non-Newtonian flow problems
He, X.; Neytcheva, M.; Vuik, C.
2013-01-01
This paper deals with fast and reliable numerical solution methods for the incompressible non-Newtonian Navier-Stokes equations. To handle the nonlinearity of the governing equations, the Picard and Newton methods are used to linearize these coupled partial differential equations. For space
Flocking particles in a non-Newtonian shear thickening fluid
Mucha, Piotr B.; Peszek, Jan; Pokorný, Milan
2018-06-01
We prove the existence of strong solutions to the Cucker–Smale flocking model coupled with an incompressible viscous non-Newtonian fluid with the stress tensor of a power–law structure for . The fluid part of the system admits strong solutions while the solutions to the CS part are weak. The coupling is performed through a drag force on a periodic spatial domain . Additionally, we construct a Lyapunov functional determining the large time behavior of solutions to the system.
A Lagrangian PFEM approach for non-Newtonian viscoplastic materials
Larese, A.
2017-01-01
This paper presents the application of a stabilized mixed Particle Finite Element Method (PFEM) to the solution of viscoplastic non-Newtonian flows. The application of the proposed model to the deformation of granular non-cohesive material is analysed. A variable yield threshold modified Bingham model is presented, using a Mohr Coulomb resistance criterion. Since the granular material is expected to undergo severe deformation, a Lagrangian approach is preferred to a fixed mesh one. PFEM i...
Structural Optimization of Non-Newtonian Rectifiers
DEFF Research Database (Denmark)
Jensen, Kristian Ejlebjærg; Okkels, Fridolin
When the size of fluidic devices is scaled down, inertial effects start to vanish such that the governing equation becomes linear. Some microfluidic devices rely on the non-linear term related to the inertia of the fluid, and one example is fluid rectifiers (diodes) e.g. related to some micropumps....... These rectifiers rely on the device geometry for their working mechanism, but on further downscaling the inertial effect vanishes and the governing equation starts to show symmetry properties. These symmetry properties reduce the geometry influence to the point where fluid rectifiers cease to function....... In this context it is natural to look for other sources of non-linearity and one possibility is to introduce a non-Newtonian working fluid. Non-Newtonian properties are due to stretching of large particles/molecules in the fluid and this is commonly seen for biological samples in “lab-on-a-chip” systems...
Attractors of equations of non-Newtonian fluid dynamics
International Nuclear Information System (INIS)
Zvyagin, V G; Kondrat'ev, S K
2014-01-01
This survey describes a version of the trajectory-attractor method, which is applied to study the limit asymptotic behaviour of solutions of equations of non-Newtonian fluid dynamics. The trajectory-attractor method emerged in papers of the Russian mathematicians Vishik and Chepyzhov and the American mathematician Sell under the condition that the corresponding trajectory spaces be invariant under the translation semigroup. The need for such an approach was caused by the fact that for many equations of mathematical physics for which the Cauchy initial-value problem has a global (weak) solution with respect to the time, the uniqueness of such a solution has either not been established or does not hold. In particular, this is the case for equations of fluid dynamics. At the same time, trajectory spaces invariant under the translation semigroup could not be constructed for many equations of non-Newtonian fluid dynamics. In this connection, a different approach to the construction of trajectory attractors for dissipative systems was proposed in papers of Zvyagin and Vorotnikov without using invariance of trajectory spaces under the translation semigroup and is based on the topological lemma of Shura-Bura. This paper presents examples of equations of non-Newtonian fluid dynamics (the Jeffreys system describing movement of the Earth's crust, the model of motion of weak aqueous solutions of polymers, a system with memory) for which the aforementioned construction is used to prove the existence of attractors in both the autonomous and the non-autonomous cases. At the beginning of the paper there is also a brief exposition of the results of Ladyzhenskaya on the existence of attractors of the two-dimensional Navier-Stokes system and the result of Vishik and Chepyzhov for the case of attractors of the three-dimensional Navier-Stokes system. Bibliography: 34 titles
Applying Tiab’s direct synthesis technique to dilatant non-Newtonian/Newtonian fluids
Directory of Open Access Journals (Sweden)
Javier Andrés Martínez
2011-09-01
Full Text Available Non-Newtonian fluids, such as polymer solutions, have been used by the oil industry for many years as fracturing agents and drilling mud. These solutions, which normally include thickened water and jelled fluids, are injected into the formation to enhanced oil recovery by improving sweep efficiency. It is worth noting that some heavy oils behave non-Newtonianly. Non-Newtonian fluids do not have direct proportionality between applied shear stress and shear rate and viscosity varies with shear rate depending on whether the fluid is either pseudoplastic or dilatant. Viscosity decreases as shear rate increases for the former whilst the reverse takes place for dilatants. Mathematical models of conventional fluids thus fail when applied to non-Newtonian fluids. The pressure derivative curve is introduced in this descriptive work for a dilatant fluid and its pattern was observed. Tiab’s direct synthesis (TDS methodology was used as a tool for interpreting pressure transient data to estimate effective permeability, skin factors and non-Newtonian bank radius. The methodology was successfully verified by its application to synthetic examples. Also, comparing it to pseudoplastic behavior, it was found that the radial flow regime in the Newtonian zone of dilatant fluids took longer to form regarding both the flow behavior index and consistency factor.
Structural Optimization of non-Newtonian Microfluidics
DEFF Research Database (Denmark)
Jensen, Kristian Ejlebjærg
2013-01-01
Many of the biological fluids analyzed in Lab-on-a-Chip systems contain elastic components, which gives the fluids elastic character. Such fluids are said to be non-Newtonian or, more precisely, viscoelastic. They can give rise to exotic effects on the macroscale, which are never seen for fluids...... with components relying on viscoelastic effects, but the non-intuitive nature of these fluids complicates the design process. This thesis combines the method of topology optimization with differential constitutive equations, which govern the flow of viscoelastic fluids. The optimization method iteratively...... finite element package. The code is capable of calculating the viscoelastic flow in a benchmark geometry, and we hope that it will help newcomers as well as experienced researchers in the field of differential constitutive equations. v...
On approximation of non-Newtonian fluid flow by the finite element method
Svácek, Petr
2008-08-01
In this paper the problem of numerical approximation of non-Newtonian fluid flow with free surface is considered. Namely, the flow of fresh concrete is addressed. Industrial mixtures often behaves like non-Newtonian fluids exhibiting a yield stress that needs to be overcome for the flow to take place, cf. [R.B. Bird, R.C. Armstrong, O. Hassager, Dynamics of Polymeric Liquids, vol. 1, Fluid Mechanics, Wiley, New York, 1987; R.P. Chhabra, J.F. Richardson, Non-Newtonian Flow in the Process Industries, Butterworth-Heinemann, London, 1999]. The main interest is paid to the mathematical formulation of the problem and to discretization with the aid of finite element method. The described numerical procedure is applied onto the solution of several problems.
Negative wake behind bubbles in non-newtonian liquids
DEFF Research Database (Denmark)
Hassager, Ole
1979-01-01
Gas bubbles rising by gravity in non-Newtonian elastic liquids are different to gas bubbles in viscous Newtonian fluids in at least two ways. First, the bubbles in the non-Newtonian liquids often have a peculiar tip at the rear pole, and second, the terminal rise velocity versus volume curve ofte...
Unsteady non-Newtonian hydrodynamics in granular gases.
Astillero, Antonio; Santos, Andrés
2012-02-01
The temporal evolution of a dilute granular gas, both in a compressible flow (uniform longitudinal flow) and in an incompressible flow (uniform shear flow), is investigated by means of the direct simulation Monte Carlo method to solve the Boltzmann equation. Emphasis is laid on the identification of a first "kinetic" stage (where the physical properties are strongly dependent on the initial state) subsequently followed by an unsteady "hydrodynamic" stage (where the momentum fluxes are well-defined non-Newtonian functions of the rate of strain). The simulation data are seen to support this two-stage scenario. Furthermore, the rheological functions obtained from simulation are well described by an approximate analytical solution of a model kinetic equation. © 2012 American Physical Society
Non-Newtonian fluid flow in annular pipes and entropy generation ...
Indian Academy of Sciences (India)
analytical solution for the flow of third-grade non-Newtonian fluid in a pipe .... where c1,c2,d1,d2,t0,1,2...7,h1,h2,k1,2... ,12,m1 and m2 are defined as ..... Yurusoy M 2004 Flow of a third grade fluid between concentric circular cylinders. Math.
Hydrodynamically Coupled Brownian Dynamics simulations for flow on non-Newtonian fluids
Ahuja, Vishal Raju
2018-01-01
This thesis deals with model development for particle-based flow simulations of non-Newtonian fluids such as polymer solutions. A novel computational technique called Hydrodynamically Coupled Brownian Dynamics (HCBD) is presented in this thesis. This technique essentially couples the Brownian motion
Impinging jet spray formation using non-Newtonian liquids
Rodrigues, Neil S.
Over the past two decades there has been a heightened interest in implementing gelled propellants for rocket propulsion, especially for hypergolic bi-propellants such as monomethylhydrazine (MMH) and nitrogen tetroxide oxidizer (NTO). Due to the very high level of toxicity of hypergolic liquid rocket propellants, increasing safety is an important area of need for continued space exploration and defense operations. Gelled propellants provide an attractive solution to meeting the requirements for safety, while also potentially improving performance. A gelling agent can be added to liquid propellants exhibiting Newtonian behavior to transform the liquid into a non-Newtonian fluid with some solid-like behavior, i.e. a gel. Non-Newtonian jet impingement is very different from its Newtonian counterpart in terms of fluid flow, atomization, and combustion. This is due to the added agents changing physical properties such as the bulk rheology (viscosity) and interfacial rheology (surface tension). Spray characterization of jet impingement with Newtonian liquids has been studied extensively in existing literature. However, there is a scarcity in literature of studies that consider the spray characterization of jet impingement with gelled propellants. This is a rather critical void since a major tradeoff of utilizing gelled propellants is the difficulty with atomization due to the increased effective viscosity. However, this difficulty can be overcome by using gels that exhibit shear-thinning behavior---viscosity decreases with increasing strain rate. Shear-thinning fluids are ideal because they have the distinct advantage of only flowing easily upon pressure. Thereby, greatly reducing the amount of propellant that could be accidentally leaked during both critical functions such as liftoff or engagement in the battlefield and regular tasks like refilling propellant tanks. This experimental work seeks to help resolve the scarcity in existing literature by providing drop size
Non-Newtonian Aspects of Artificial Intelligence
Zak, Michail
2016-05-01
The challenge of this work is to connect physics with the concept of intelligence. By intelligence we understand a capability to move from disorder to order without external resources, i.e., in violation of the second law of thermodynamics. The objective is to find such a mathematical object described by ODE that possesses such a capability. The proposed approach is based upon modification of the Madelung version of the Schrodinger equation by replacing the force following from quantum potential with non-conservative forces that link to the concept of information. A mathematical formalism suggests that a hypothetical intelligent particle, besides the capability to move against the second law of thermodynamics, acquires such properties like self-image, self-awareness, self-supervision, etc. that are typical for Livings. However since this particle being a quantum-classical hybrid acquires non-Newtonian and non-quantum properties, it does not belong to the physics matter as we know it: the modern physics should be complemented with the concept of the information force that represents a bridge to intelligent particle. As a follow-up of the proposed concept, the following question is addressed: can artificial intelligence (AI) system composed only of physical components compete with a human? The answer is proven to be negative if the AI system is based only on simulations, and positive if digital devices are included. It has been demonstrated that there exists such a quantum neural net that performs simulations combined with digital punctuations. The universality of this quantum-classical hybrid is in capability to violate the second law of thermodynamics by moving from disorder to order without external resources. This advanced capability is illustrated by examples. In conclusion, a mathematical machinery of the perception that is the fundamental part of a cognition process as well as intelligence is introduced and discussed.
Increasing heat transfer of non-Newtonian nanofluid in rectangular microchannel with triangular ribs
Shamsi, Mohammad Reza; Akbari, Omid Ali; Marzban, Ali; Toghraie, Davood; Mashayekhi, Ramin
2017-09-01
In this study, computational fluid dynamics and the laminar flow of the non-Newtonian fluid have been numerically studied. The cooling fluid includes water and 0.5 wt% Carboxy methyl cellulose (CMC) making the non-Newtonian fluid. In order to make the best of non-Newtonian nanofluid in this simulation, solid nanoparticles of Aluminum Oxide have been added to the non-Newtonian fluid in volume fractions of 0-2% with diameters of 25, 45 and 100 nm. The supposed microchannel is rectangular and two-dimensional in Cartesian coordination. The power law has been used to speculate the dynamic viscosity of the cooling nanofluid. The field of numerical solution is simulated in the Reynolds number range of 5 nanoparticles as well as the use for nanoparticles with smaller diameters lead to greater heat transfer. Among all the studied forms, the triangular rib from with an angle of attack 30° has the biggest Nusselt number and the smallest pressure drop along the microchannel. Also, an increase in the angle of attack and as a result of a sudden contact between the fluid and the ribs and also a reduction in the coflowing length (length of the rib) cause a cut in heat transfer by the fluid in farther parts from the solid wall (tip of the rib).
Studying mixing in Non-Newtonian blue maize flour suspensions using color analysis.
Directory of Open Access Journals (Sweden)
Grissel Trujillo-de Santiago
Full Text Available BACKGROUND: Non-Newtonian fluids occur in many relevant flow and mixing scenarios at the lab and industrial scale. The addition of acid or basic solutions to a non-Newtonian fluid is not an infrequent operation, particularly in Biotechnology applications where the pH of Non-Newtonian culture broths is usually regulated using this strategy. METHODOLOGY AND FINDINGS: We conducted mixing experiments in agitated vessels using Non-Newtonian blue maize flour suspensions. Acid or basic pulses were injected to reveal mixing patterns and flow structures and to follow their time evolution. No foreign pH indicator was used as blue maize flours naturally contain anthocyanins that act as a native, wide spectrum, pH indicator. We describe a novel method to quantitate mixedness and mixing evolution through Dynamic Color Analysis (DCA in this system. Color readings corresponding to different times and locations within the mixing vessel were taken with a digital camera (or a colorimeter and translated to the CIELab scale of colors. We use distances in the Lab space, a 3D color space, between a particular mixing state and the final mixing point to characterize segregation/mixing in the system. CONCLUSION AND RELEVANCE: Blue maize suspensions represent an adequate and flexible model to study mixing (and fluid mechanics in general in Non-Newtonian suspensions using acid/base tracer injections. Simple strategies based on the evaluation of color distances in the CIELab space (or other scales such as HSB can be adapted to characterize mixedness and mixing evolution in experiments using blue maize suspensions.
Non-newtonian heat transfer on a plate heat exchanger with generalized configurations
Energy Technology Data Exchange (ETDEWEB)
Carezzato, A.; Tadini, C.C.; Gut, J.A.W. [Department of Chemical Engineering, Escola Politecnica, University of Sao Paulo, Sao Paulo (Brazil); Alcantara, M.R. [Department of Fundamental Chemistry, Institute of Chemistry, University of Sao Paulo, Sao Paulo (Brazil); Telis-Romero, J. [Department of Food Engineering and Technology, Universidade Estadual Paulista, Sao Jose do Rio Preto (Brazil)
2007-01-15
For the configuration optimization of plate heat exchangers (PHEs), the mathematical models for heat transfer and pressure drop must be valid for a wide range of operational conditions of all configurations of the exchanger or the design results may be compromised. In this investigation, the thermal model of a PHE is adjusted to fit experimental data obtained from non-Newtonian heat transfer for eight different configurations, using carboxymethylcellulose solutions (CMC) as test fluid. Although it is possible to successfully adjust the model parameters, Newtonian and non-Newtonian heat transfer cannot be represented by a single generalized correlation. In addition, the specific heat, thermal conductivity and power-law rheological parameters of CMC solutions were correlated with temperature, over a range compatible with a continuous pasteurization process. (Abstract Copyright [2007], Wiley Periodicals, Inc.)
On Numerical Methods in Non-Newtonian Flows
International Nuclear Information System (INIS)
Fileas, G.
1982-12-01
The constitutive equations for non-Newtonian flows are presented and the various flow models derived from continuum mechanics and molecular theories are considered and evaluated. Detailed account is given of numerical simulation employing differential and integral models of different kinds of non-Newtonian flows using finite-difference and finite-element techniques. Appreciating the fact that no book or concentrated material on Numerical Non-Newtonian Fluid Flow exists at the present, procedures for computer set-ups are described and references are given for finite-difference, finite-element and molecular-theory based programmes for several kinds of flow. Achievements and unreached goals in the field of numerical simulation of non-Newtonian flows are discussed and the lack of numerical work in the fields of suspension flows and heat transfer is pointed out. Finally, FFOCUS is presented as a newly built computer program which can simulate freezing flows on Newtonian fluids through various geometries and is aimed to be further developed to handle non-Newtonian freezing flows and certain types of suspension phenomena involved in corium flow after a hypothetical core melt-down accident in a PWR. (author)
Dynamic characteristics of Non Newtonian fluid Squeeze film damper
Palaksha, C. P.; Shivaprakash, S.; Jagadish, H. P.
2016-09-01
The fluids which do not follow linear relationship between rate of strain and shear stress are termed as non-Newtonian fluid. The non-Newtonian fluids are usually categorized as those in which shear stress depends on the rates of shear only, fluids for which relation between shear stress and rate of shear depends on time and the visco inelastic fluids which possess both elastic and viscous properties. It is quite difficult to provide a single constitutive relation that can be used to define a non-Newtonian fluid due to a great diversity found in its physical structure. Non-Newtonian fluids can present a complex rheological behaviour involving shear-thinning, viscoelastic or thixotropic effects. The rheological characterization of complex fluids is an important issue in many areas. The paper analyses the damping and stiffness characteristics of non-Newtonian fluids (waxy crude oil) used in squeeze film dampers using the available literature for viscosity characterization. Damping and stiffness characteristic will be evaluated as a function of shear strain rate, temperature and percentage wax concentration etc.
Directory of Open Access Journals (Sweden)
Yan Zhang
2011-01-01
Full Text Available The problem of steady, laminar, thermal Marangoni convection flow of non-Newtonian power law fluid along a horizontal surface with variable surface temperature is studied. The partial differential equations are transformed into ordinary differential equations by using a suitable similarity transformation and analytical approximate solutions are obtained by an efficient transformation, asymptotic expansion and Padé approximants technique. The effects of power law index and Marangoni number on velocity and temperature profiles are examined and discussed.
Boundary layer for non-newtonian fluids on curved surfaces
International Nuclear Information System (INIS)
Stenger, N.
1981-04-01
By using the basic equation of fluid motion (conservation of mass and momentum) the boundary layer parameters for a Non-Newtonian, incompressible and laminar fluid flow, has been evaluated. As a test, the flat plate boundary layer is first analized and afterwards, a case with pressure gradient, allowing separation, is studied. In the case of curved surfaces, the problem is first developed in general and afterwards particularized to a circular cylinder. Finally suction and slip in the flow interface are examined. The power law model is used to represent the stress strain relationship in Non-Newtonian flow. By varying the fluid exponent one can then, have an idea of how the Non-Newtonian behavior of the flow influences the parameters of the boundary layer. Two equations, in an appropriate coordinate system have been obtained after an order of magnitude analysis of the terms in the equations of motion is performed. (Author) [pt
The effect of the expansion ratio on a turbulent non-Newtonian recirculating flow
Energy Technology Data Exchange (ETDEWEB)
Pereira, A.S. [Departamento de Engenharia Quimica Instituto Superior de Engenharia do Porto (Portugal); Pinho, F.T. [Centro de Estudos de Fenomenos de Transporte, DEMEGI, Faculdade de Engenharia, Universidade do Porto (Portugal)
2002-04-01
Measurements of the mean and turbulent flow characteristics of shear-thinning moderately elastic 0.1% and 0.2% xanthan gum aqueous solutions were carried out in a sudden expansion having a diameter ratio of 2. The inlet flow was turbulent and fully developed, and the results were compared with data for water in the same geometry and with previous published Newtonian and non-Newtonian data in a smaller expansion of diameter ratio equal to 1.538. An increase in expansion ratio led to an increase in the recirculation length and in the axial normal Reynolds stress at identical normalised locations, but the difference between Newtonian and non-Newtonian characteristics was less intense than in the smaller expansion. An extensive comparison of mean and turbulent flow characteristics was carried out in order to understand the variation of flow features. (orig.)
Non-Newtonian Flow-Induced Deformation From Pressurized Cavities in Absorbing Porous Tissues
Ahmed, Aftab; Siddique, Javed
2017-11-01
We investigate the behavior of a spherical cavity in a soft biological tissue modeled as a deformable porous material during an injection of non-Newtonian fluid that follows a power law model. Fluid flows into the neighboring tissue due to high cavity pressure where it is absorbed by capillaries and lymphatics at a rate proportional to the local pressure. Power law fluid pressure and displacement of solid in the tissue are computed as function of radial distance and time. Numerical solutions indicate that shear thickening fluids exhibit less fluid pressure and induce small solid deformation as compared to shear thinning fluids. The absorption in the biological tissue increases as a consequence of flow induced deformation for power law fluids. In most cases non-Newtonian results are compared with viscous fluid case to magnify the differences.
Comparative PIV and LDA studies of Newtonian and non-Newtonian flows in an agitated tank.
Story, Anna; Jaworski, Zdzisław; Simmons, Mark J; Nowak, Emilia
2018-01-01
The paper presents results of an experimental study of the fluid velocity field in a stirred tank equipped with a Prochem Maxflo T (PMT) type impeller which was rotating at a constant frequency of N = 4.1 or 8.2 s -1 inducing transitional ( Re = 499 or 1307) or turbulent ( Re = 2.43 × 10 4 ) flow of the fluid. The experiments were performed for a Newtonian fluid (water) and a non-Newtonian fluid (0.2 wt% aqueous solution of carboxymethyl cellulose, CMC) exhibiting mild viscoelastic properties. Measurements were carried out using laser light scattering on tracer particles which follow the flow (2-D PIV). For both the water and the CMC solution one primary and two secondary circulation loops were observed within the fluid volume; however, the secondary loops were characterized by much lower intensity. The applied PMT-type impeller produced in the Newtonian fluid an axial primary flow, whilst in the non-Newtonian fluid the flow was more radial. The results obtained in the form of the local mean velocity components were in satisfactory agreement with the literature data from LDA. Distribution of the shear rate in the studied system was also analyzed. For the non-Newtonian fluid an area was computed where the elastic force dominates over the viscous one. The area was nearly matching the region occupied by the primary circulation loop.
Directory of Open Access Journals (Sweden)
J. Javorova
2016-06-01
Full Text Available The purpose of this paper is to study the performance of a finite length journal bearing, taking into account effects of non-Newtonian Rabinowitsch flow rheology and elastic deformations of the bearing liner. According to the Rabinowitsch fluid model, the cubic-stress constitutive equation is used to account for the non-Newtonian effects of pseudoplastic and dilatant lubricants. Integrating the continuity equation across the film, the nonlinear non-Newtonian Reynolds-type equation is derived. The elasticity part of the problem is solved on the base of Vlassov model of an elastic foundation. The numerical solution of the modified Reynolds equation is carried out by using FDM with over-relaxation technique. The results for steady state bearing performance characteristics have been calculated for various values of nonlinear factor and elasticity parameters. It was concluded that in comparison with the Newtonian lubricants, higher values of film pressure and load carrying capacity have been obtained for dilatant lubricants, while the case was reversed for pseudoplastic lubricants.
Nonlinear shear wave in a non Newtonian visco-elastic medium
Energy Technology Data Exchange (ETDEWEB)
Banerjee, D.; Janaki, M. S.; Chakrabarti, N. [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Calcutta 700 064 (India); Chaudhuri, M. [Max-Planck-Institut fuer extraterrestrische Physik, 85741 Garching (Germany)
2012-06-15
An analysis of nonlinear transverse shear wave has been carried out on non-Newtonian viscoelastic liquid using generalized hydrodynamic model. The nonlinear viscoelastic behavior is introduced through velocity shear dependence of viscosity coefficient by well known Carreau-Bird model. The dynamical feature of this shear wave leads to the celebrated Fermi-Pasta-Ulam problem. Numerical solution has been obtained which shows that initial periodic solutions reoccur after passing through several patterns of periodic waves. A possible explanation for this periodic solution is given by constructing modified Korteweg de Vries equation. This model has application from laboratory to astrophysical plasmas as well as in biological systems.
Non-Newtonian fluid flow in an axisymmetric channel with porous wall
Directory of Open Access Journals (Sweden)
M. Hosseini
2013-12-01
Full Text Available In the present article Optimal Homotopy Asymptotic Method (OHAM is used to obtain the solutions of momentum and heat transfer equations of non-Newtonian fluid flow in an axisymmetric channel with porous wall for turbine cooling applications. Numerical method is used for validity of this analytical method and excellent agreement is observed between the solutions obtained from OHAM and numerical results. Trusting to this validity, effects of some other parameters are discussed. The results show that Nusselt number increases with increase of Reynolds number, Prandtl number and power law index.
Non-Newtonian fluid structure interaction in flexible biomimetic microchannels
Kiran, M.; Dasgupta, Sunando; Chakraborty, Suman
2017-11-01
To investigate the complex fluid structure interactions in a physiologically relevant microchannel with deformable wall and non-Newtonian fluid that flows within it, we fabricated cylindrical microchannels of various softness out of PDMS. Experiments to measure the transient pressure drop across the channel were carried out with high sampling frequencies to capture the intricate flow physics. In particular, we showed that the waveforms varies greatly for each of the non-Newtonian and Newtonian cases for both non-deformable and deformable microchannels in terms of the peak amplitude, r.m.s amplitude and the crest factor. In addition, we carried out frequency sweep experiments to evaluate the frequency response of the system. We believe that these results will aid in the design of polymer based microfluidic phantoms for arterial FSI studies, and in particular for studying blood analog fluids in cylindrical microchannels as well as developing frequency specific Lab-on-chip systems for medical diagnostics.
Verification of vertically rotating flume using non-newtonian fluids
Huizinga, R.J.
1996-01-01
Three tests on non-Newtonian fluids were used to verify the use of a vertically rotating flume (VRF) for the study of the rheological properties of debris flow. The VRF is described and a procedure for the analysis of results of tests made with the VRF is presented. The major advantages of the VRF are a flow field consistent with that found in nature, a large particle-diameter threshold, inexpensive operation, and verification using several different materials; the major limitations are a lack of temperature control and a certain error incurred from the use of the Bingham plastic model to describe a more complex phenomenon. Because the VRF has been verified with non-Newtonian fluids as well as Newtonian fluids, it can be used to measure the rheological properties of coarse-grained debris-flow materials.
Non-Newtonian ink transfer in gravure-offset printing
International Nuclear Information System (INIS)
Ghadiri, Fatemeh; Ahmed, Dewan Hasan; Sung, Hyung Jin; Shirani, Ebrahim
2011-01-01
The inks used in gravure-offset printing are non-Newtonian fluids with higher viscosities and lower surface tensions than Newtonian fluids. This paper examines the transfer of a non-Newtonian ink between a flat plate and a groove when the plate is moved upward with a constant velocity while the groove is held fixed. Numerical simulations were carried out with the Carreau model to explore the behavior of this non-Newtonian ink in gravure-offset printing. The volume of fluid (VOF) method was implemented to capture the interface during the ink transfer process. The effects of varying the contact angle of the ink on the flat plate and groove walls and geometrical parameters such as the groove angle and the groove depth on the breakup time of the liquid filament that forms between the plate and the groove and the ink transfer ratio were determined. Our results indicate that increasing the groove contact angle and decreasing the flat plate contact angle enhance the ink transfer ratio and the breakup time. However, increasing the groove depth and the groove angle decreases the transfer ratio and the breakup time. By optimizing these parameters, it is possible to achieve an ink transfer from the groove to the flat plate of approximately 92%. Moreover, the initial width and the vertical velocity of the neck of the ink filament have significant influences on the ink transfer ratio and the breakup time.
Generation of Oil Droplets in a Non-Newtonian Liquid Using a Microfluidic T-Junction
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Enrico Chiarello
2015-11-01
Full Text Available We have compared the formation of oil drops in Newtonian and non-Newtonian fluids in a T-junction microfluidic device. As Newtonian fluids, we used aqueous solutions of glycerol, while as non-Newtonian fluids we prepared aqueous solutions of xanthan, a stiff rod-like polysaccharide, which exhibit strong shear-thinning effects. In the squeezing regime, the formation of oil droplets in glycerol solutions is found to scale with the ratio of the dispersed flow rate to the continuous one and with the capillary number associated to the continuous phase. Switching to xanthan solutions does not seem to significantly alter the droplet formation process. Any quantitative difference with respect to the Newtonian liquid can be accounted for by a suitable choice of the capillary number, corresponding to an effective xanthan viscosity that depends on the flow rates. We have deduced ample variations in the viscosity, on the order of 10 and more, during normal operation conditions of the T-junction. This allowed estimating the actual shear rates experienced by the xanthan solutions, which go from tens to hundreds of s−1.
Numerical investigation of non-Newtonian nanofluid flow in a converging microchannel
Energy Technology Data Exchange (ETDEWEB)
Mohsenian, S.; Ramiar, A.; Ranjbar, A. A. [Faculty of Mechanical Engineering, Babol Noshirvani University of Technology, Babol (Iran, Islamic Republic of)
2017-01-15
In the present study the flow of non-Newtonian nanofluid through a converging microchannel is investigated numerically. TiO{sub 2} nanoparticles with 10 nm diameter are dispersed in an aqueous solution of 0.5 %.wt Carboxymethyl cellulose (CMC) to produce the nanofluid. Both nanofluid and the base fluid show pseudoplastic behavior. The equations have been solved with finite volume approach using collocated grid. It has been found that by increasing the volume fraction and Reynolds number and the convergence angle, the Nusselt number increases. Also, it has been observed that by increasing convergence angle and decreasing aspect ratio of the channel, the velocity of the channel increases.
Open mathematical problems regarding non-Newtonian fluids
International Nuclear Information System (INIS)
Wilson, Helen J
2012-01-01
We present three open problems in the mathematical modelling of the flow of non-Newtonian fluids. The first problem is rather long standing: a discontinuity in the dependence of the rise velocity of a gas bubble on its volume. This is very well characterized experimentally but not, so far, fully reproduced either numerically or analytically. The other two are both instabilities. The first is observed experimentally but never predicted analytically or numerically. In the second instability, numerical studies reproduce the experimental observations but there is as yet no analytical or semi-analytical prediction of the linear instability which must be present. (invited article)
Viscosity of Heterogeneous Silicate Melts: A Non-Newtonian Model
Liu, Zhuangzhuang; Blanpain, Bart; Guo, Muxing
2017-12-01
The recently published viscosity data of heterogeneous silicate melts with well-documented structure and experimental conditions are critically re-analyzed and tabulated. By using these data, a non-Newtonian viscosity model incorporating solid fraction, solid shape, and shear rate is proposed on the basis of the power-law equation. This model allows calculating the viscosity of the heterogeneous silicate melts with solid fraction up to 34 vol pct. The error between the calculated and measured data is evaluated to be 32 pct, which is acceptable considering the large error in viscosity measurement of the completely liquid silicate melt.
Gas holdup in a reciprocating plate bioreactor: Non-Newtonian - liquid phase
Directory of Open Access Journals (Sweden)
Naseva Olivera S.
2002-01-01
Full Text Available The gas holdup was studied in non-newtonian liquids in a gas-liquid and gas-liquid-solid reciprocating plate bioreactor. Aqueous solutions of carboxy methyl cellulose (CMC; Lucel, Lučane, Yugoslavia of different degrees of polymerization (PP 200 and PP 1000 and concentration (0,5 and 1%, polypropylene spheres (diameter 8.3 mm; fraction of spheres: 3.8 and 6.6% by volume and air were used as the liquid, solid and gas phase. The gas holdup was found to be dependent on the vibration rate, the superficial gas velocity, volume fraction of solid particles and Theological properties of the liquid ohase. Both in the gas-liquid and gas-liquid-solid systems studied, the gas holdup increased with increasing vibration rate and gas flow rate. The gas holdup was higher in three-phase systems than in two-phase ones under otter operating conditions being the same. Generally the gas holdup increased with increasing the volume fraction of solid particles, due to the dispersion action of the solid particles, and decreased with increasing non-Newtonian behaviour (decreasing flow index i.e. with increasing degree of polymerization and solution concentration of CMC applied, as a result of gas bubble coalescence.
Nonisothermal flow of a non-Newtonian fluid with viscous heating between two parallel plates
International Nuclear Information System (INIS)
Imal, M.; Pinarbasi, A.
2004-01-01
In this study the pressure gradient-flow rate relationship for steady-state nonisothermal pressure-driven flow of a non-Newtonian fluid in a channel is investigated including the effect of viscous heating is taken into account. The viscosity of the fluid depends on both temperature and shear-rate. Exponential dependence of viscosity on temperature is modelled through Arrhenius law. Non-Newtonian behaviour of the fluid is modelled according to the Carreau rheological equation, which reflects the characteristics of most polymers adequately with an exponential temperature dependence of viscosity. Flow governing motion and energy balance equations are coupled and solution of this non-linear boundary value problem is found iteratively using a pseudo spectral method based on Chebyshev polynomials. The effect of activation energy parameter and Brinkman number, as well as the power-law index and material time constant on the flow is studied. It is found that while the pressure gradient-flow rate graph is monotonic for certain ranges of flow controlling parameters, there is a large jump in the graph under certain values of these parameters.(1 table and 5 figures are included.)
International Nuclear Information System (INIS)
Lamsaadi, M.; Naimi, M.; Hasnaoui, M.
2006-01-01
A combined analytical and numerical study is conducted for two dimensional, steady state, buoyancy driven flows of non-Newtonian power law fluids confined in a shallow rectangular cavity submitted to uniform fluxes of heat along both its short vertical sides, while its long horizontal walls are considered adiabatic. The effect of the non-Newtonian behavior on the fluid flow and heat transfer characteristics is examined. An approximate theoretical solution is developed on the basis of the parallel flow assumption and validated numerically by solving the full governing equations
Energy Technology Data Exchange (ETDEWEB)
Guenther, Chris [National Energy Technology Lab. (NETL), Morgantown, WV (United States); Garg, Rahul [National Energy Technology Lab. (NETL), Morgantown, WV (United States)
2013-08-19
The Department of Energy’s (DOE) National Energy Technology Laboratory (NETL) sponsored a workshop on non-Newtonian multiphase slurry at NETL’s Morgantown campus August 19 and 20, 2013. The objective of this special two-day meeting of 20-30 invited experts from industry, National Labs and academia was to identify and address technical issues associated with handling non-Newtonian multiphase slurries across various facilities managed by DOE. Particular emphasis during this workshop was placed on applications managed by the Office of Environmental Management (EM). The workshop was preceded by two webinars wherein personnel from ORP and NETL provided background information on the Hanford WTP project and discussed the critical design challenges facing this project. In non-Newtonian fluids, viscosity is not constant and exhibits a complex dependence on applied shear stress or deformation. Many applications under EM’s tank farm mission involve non-Newtonian slurries that are multiphase in nature; tank farm storage and handling, slurry transport, and mixing all involve multiphase flow dynamics, which require an improved understanding of the mechanisms responsible for rheological changes in non-Newtonian multiphase slurries (NNMS). To discuss the issues in predicting the behavior of NNMS, the workshop focused on two topic areas: (1) State-of-the-art in non-Newtonian Multiphase Slurry Flow, and (2) Scaling up with Confidence and Ensuring Safe and Reliable Long-Term Operation.
Numerical analysis of non-Newtonian rheology effect on hydrocyclone flow field
Directory of Open Access Journals (Sweden)
Lin Yang
2015-03-01
Full Text Available In view of the limitations of the existing Newton fluid effects on the vortex flow mechanism study, numerical analysis of non Newton fluid effects was presented. Using Reynolds stress turbulence model (RSM and mixed multiphase flow model (Mixture of FLUENT (fluid calculation software and combined with the constitutive equation of apparent viscosity of non-Newtonian fluid, the typical non-Newtonian fluid (drilling fluid, polymer flooding sewage and crude oil as medium and Newton flow field (water as medium were compared by quantitative analysis. Based on the research results of water, the effects of non-Newtonian rheology on the key parameters including the combined vortex motion index n and tangential velocity were analyzed. The study shows that: non-Newtonian rheology has a great effect on tangential velocity and n value, and tangential velocity decreases with non-Newtonian increasing. The three kinds of n values (constant segment are: 0.564(water, 0.769(polymer flooding sewage, 0.708(drilling fluid and their variation amplitudes are larger than Newtonian fluid. The same time, non-Newtonian rheology will lead to the phenomenon of turbulent drag reduction in the vortex flow field. Compared with the existing formula calculation results shown, the calculation result of non-Newtonian rheology is most consistent with the simulation result, and the original theory has large deviations. The study provides reference for theory research of non-Newtonian cyclone separation flow field.
A boundary integral method for two-dimensional (non)-Newtonian drops in slow viscous flow
Toose, E.M.; Geurts, B.J.; Kuerten, J.G.M.
1995-01-01
A boundary integral method for the simulation of the time-dependent deformation of Newtonian or non-Newtonian drops suspended in a Newtonian fluid is developed. The boundary integral formulation for Stokes flow is used and the non-Newtonian stress is treated as a source term which yields an extra
Experimental investigation of non-Newtonian droplet collisions : the role of extensional viscosity
Finotello, Giulia; De, Shauvik; Vrouwenvelder, Jeroen C.R.; Padding, J.T.; Buist, Kay A.; Jongsma, Alfred; Innings, Fredrik; Kuipers, J.
2018-01-01
We investigate the collision behaviour of a shear thinning non-Newtonian fluid xanthan, by binary droplet collision experiments. Droplet collisions of non-Newtonian fluids are more complex than their Newtonian counterpart as the viscosity no longer remains constant during the collision process.
Interplay between inertial and non-Newtonian effects on the flow in weakly modulated channel
International Nuclear Information System (INIS)
Abu-Ramadan, E.; Khayat, R.E.
2002-01-01
The flow inside a spatially modulated channel is examined for shear-thinning and shear-thickening fluids. The modulation amplitude is assumed to be small. A regular perturbation expansion of the flow field is used, coupled to a variable-step finite-difference scheme, to solve the problem. Since this method is intended to provide a fast and accurate alternative to conventional methods in the limit of small modulation amplitude, establishing the accuracy of the solution is critical. Numerical accuracy and convergence will be assessed, therefore. The influence of the wall geometry, inertia and non-Newtonian effects are investigated systematically. In particular, the influence of the flow and fluid parameters is examined on the conditions for the onset of separation. (author)
Aerosol entrainment from a sparged non-Newtonian slurry.
Fritz, Brad G
2006-08-01
Previous bench-scale experiments have provided data necessary for the development of empirical models that describe aerosol entrainment from bubble bursting. However, previous work has not been extended to non-Newtonian liquid slurries. Design of a waste treatment plant on the Hanford Site in Washington required an evaluation of the applicability of these models outside of their intended range. For this evaluation, aerosol measurements were conducted above an air-sparged mixing tank filled with simulated waste slurry possessing Bingham plastic rheological properties. Three aerosol-size fractions were measured at three sampling heights and for three different sparging rates. The measured entrainment was compared with entrainment models. One model developed based on bench-scale air-water experiments agreed well with measured entrainment. Another model did not agree well with the measured entrainment. It appeared that the source of discrepancy between measured and modeled entrainment stemmed from application beyond the range of data used to develop the model. A possible separation in entrainment coefficients between air-water and steam-water systems was identified. A third entrainment model was adapted to match experimental conditions and fit a posteri to the experimental data, resulting in a modified version that resulted in estimated entrainment rates similar to the first model.
A two-phase theory for non-Newtonian suspensions
Varsakelis, Christos
In this talk, a continuum and thermodynamically consistent theory for macroscopic particles immersed in a non-Newtonian fluid is presented. According to the employed methodology, each phase of the mixture is treated as a thermodynamic system, endowed with its own set of thermodynamic and kinetic variables, and is required to separately satisfy the equations for the balance of mass, momentum and energy. As both constituents of the mixture are not simple fluids, additional degrees of freedom are introduced for the proper description of their thermodynamic state. A subsequent exploitation of the entropy inequality asserts that the accommodation of the complicated rheological characteristics of both phases requires a departure from a linear current-force relationship. For this reason, a subtle nonlinear representation of the stress tensors is employed. Importantly, the inclusion of additional degrees of freedom allows us to obtain a rate equation for the evolution of the volume fraction of the particulate phase. Following a delineation of the fundamentals of the proposed theory, the talk concludes with the presentation of some limiting cases that also serve as preliminary, sanity tests.
Lie group analysis of flow and heat transfer of non-Newtonian
Indian Academy of Sciences (India)
law nanofluid over a stretching surface under convective boundary conditions and temperature-dependent fluid viscosity has been numerically investigated. The power-law rheology is adopted to describe non-Newtonian characteristics of the ...
Conceptual Models of the Climate 2003 Program of Study: Non-Newtonian Geophysical Fluid Dynamics
National Research Council Canada - National Science Library
Balmforth, NeiI
2004-01-01
Non-Newtonian fluids occur commonly in our world. These fluids, such as toothpaste, saliva, oils, mud and lava, exhibit a number of behaviors that are different from Newtonian fluids and have a number of additional material properties...
Effect of non-Newtonian viscosity on the fluid-dynamic characteristics in stenotic vessels
Huh, Hyung Kyu; Ha, Hojin; Lee, Sang Joon
2015-08-01
Although blood is known to have shear-thinning and viscoelastic properties, the effects of such properties on the hemodynamic characteristics in various vascular environments are not fully understood yet. For a quantitative hemodynamic analysis, the refractive index of a transparent blood analogue needs to be matched with that of the flowing conduit in order to minimize the errors according to the distortion of the light. In this study, three refractive index-matched blood analogue fluids with different viscosities are prepared—one Newtonian and two non-Newtonian analogues—which correspond to healthy blood with 45 % hematocrit (i.e., normal non-Newtonian) and obese blood with higher viscosity (i.e., abnormal non-Newtonian). The effects of the non-Newtonian rheological properties of the blood analogues on the hemodynamic characteristics in the post-stenosis region of an axisymmetric stenosis model are experimentally investigated using particle image velocimetry velocity field measurement technique and pathline flow visualization. As a result, the centerline jet flow from the stenosis apex is suppressed by the shear-thinning feature of the blood analogues when the Reynolds number is smaller than 500. The lengths of the recirculation zone for abnormal and normal non-Newtonian blood analogues are 3.67 and 1.72 times shorter than that for the Newtonian analogue at Reynolds numbers smaller than 200. The Reynolds number of the transition from laminar to turbulent flow for all blood analogues increases as the shear-thinning feature increases, and the maximum wall shear stresses in non-Newtonian fluids are five times greater than those in Newtonian fluids. However, the shear-thinning effect on the hemodynamic characteristics is not significant at Reynolds numbers higher than 1000. The findings of this study on refractive index-matched non-Newtonian blood analogues can be utilized in other in vitro experiments, where non-Newtonian features dominantly affect the flow
Amiri Delouei, A.; Nazari, M.; Kayhani, M. H.; Kang, S. K.; Succi, S.
2016-04-01
In the current study, a direct-forcing immersed boundary-non-Newtonian lattice Boltzmann method (IB-NLBM) is developed to investigate the sedimentation and interaction of particles in shear-thinning and shear-thickening fluids. In the proposed IB-NLBM, the non-linear mechanics of non-Newtonian particulate flows is detected by combination of the most desirable features of immersed boundary and lattice Boltzmann methods. The noticeable roles of non-Newtonian behavior on particle motion, settling velocity and generalized Reynolds number are investigated by simulating benchmark problem of one-particle sedimentation under the same generalized Archimedes number. The effects of extra force due to added accelerated mass are analyzed on the particle motion which have a significant impact on shear-thinning fluids. For the first time, the phenomena of interaction among the particles, such as Drafting, Kissing, and Tumbling in non-Newtonian fluids are investigated by simulation of two-particle sedimentation and twelve-particle sedimentation. The results show that increasing the shear-thickening behavior of fluid leads to a significant increase in the kissing time. Moreover, the transverse position of particles for shear-thinning fluids during the tumbling interval is different from Newtonian and the shear-thickening fluids. The present non-Newtonian particulate study can be applied in several industrial and scientific applications, like the non-Newtonian sedimentation behavior of particles in food industrial and biological fluids.
Study of microvascular non-Newtonian blood flow modulated by electroosmosis.
Tripathi, Dharmendra; Yadav, Ashu; Anwar Bég, O; Kumar, Rakesh
2018-05-01
An analytical study of microvascular non-Newtonian blood flow is conducted incorporating the electro-osmosis phenomenon. Blood is considered as a Bingham rheological aqueous ionic solution. An externally applied static axial electrical field is imposed on the system. The Poisson-Boltzmann equation for electrical potential distribution is implemented to accommodate the electrical double layer in the microvascular regime. With long wavelength, lubrication and Debye-Hückel approximations, the boundary value problem is rendered non-dimensional. Analytical solutions are derived for the axial velocity, volumetric flow rate, pressure gradient, volumetric flow rate, averaged volumetric flow rate along one time period, pressure rise along one wavelength and stream function. A plug swidth is featured in the solutions. Via symbolic software (Mathematica), graphical plots are generated for the influence of Bingham plug flow width parameter, electrical Debye length and Helmholtz-Smoluchowski velocity (maximum electro-osmotic velocity) on the key hydrodynamic variables. This study reveals that blood flow rate accelerates with decreasing the plug width (i.e. viscoplastic nature of fluids) and also with increasing the Debye length parameter. Copyright © 2018 Elsevier Inc. All rights reserved.
Experimental investigation of non-Newtonian/Newtonian liquid-liquid flow in microchannel
Roumpea, Eynagelia-Panagiota; Weheliye, Weheliye; Chinaud, Maxime; Angeli, Panagiota; Lyes Kahouadji Collaboration; Omar. K. Matar Collaboration
2015-11-01
Plug flow of an organic phase and an aqueous non-Newtonian solution was investigated experimentally in a quartz microchannel with I.D. 200 μm. The aqueous phase was a glycerol solution where 1000 and 2000 ppm of xanthan gum was added while the organic phase was silicon oil with 155 and 5 cSt viscosity. The two phases were brought together in a T-junction and their flowrates varied from 0.3 to 6 ml/hr. High speed imaging was used to study the characteristics of the plugs and the effect of the liquid properties on the flow patterns while a two-colour micro-PIV technique was used to investigate velocity profiles and circulation patterns within the plugs. The experimental results revealed that plug length was affected by both flowrate and viscosity. In all cases investigated, a film of the continuous phase always surrounded the plugs and its thickness was compared with existing literature models. Circulation patterns inside plugs were obtained by subtracting the plug velocity and found to be depended on the plug length and the amount of xanthan gum in the aqueous phase. Finally, the dimensionless circulation time was calculated and plotted as a function of the plug length. Department of Chemical Engineering South Kensington Campus Imperial College London SW7 2AZ.
Secondary flow in a curved artery model with Newtonian and non-Newtonian blood-analog fluids
Najjari, Mohammad Reza; Plesniak, Michael W.
2016-11-01
Steady and pulsatile flows of Newtonian and non-Newtonian fluids through a 180°-curved pipe were investigated using particle image velocimetry (PIV). The experiment was inspired by physiological pulsatile flow through large curved arteries, with a carotid artery flow rate imposed. Sodium iodide (NaI) and sodium thiocyanate (NaSCN) were added to the working fluids to match the refractive index (RI) of the test section to eliminate optical distortion. Rheological measurements revealed that adding NaI or NaSCN changes the viscoelastic properties of non-Newtonian solutions and reduces their shear-thinning property. Measured centerline velocity profiles in the upstream straight pipe agreed well with an analytical solution. In the pulsatile case, secondary flow structures, i.e. deformed-Dean, Dean, Wall and Lyne vortices, were observed in various cross sections along the curved pipe. Vortical structures at each cross section were detected using the d2 vortex identification method. Circulation analysis was performed on each vortex separately during the systolic deceleration phase, and showed that vortices split and rejoin. Secondary flow structures in steady flows were found to be morphologically similar to those in pulsatile flows for sufficiently high Dean number. supported by the George Washington University Center for Biomimetics and Bioinspired Engineering.
Effect on Non-Newtonian Rheology on Mixing in Taylor-Couette Flow
Cagney, Neil; Balabani, Stavroula
2017-11-01
Mixing processes within many industry applications are strongly affected by the rheology of the working fluid. This is particularly relevant for pharmaceutical, food and waste treatment industries, where the working fluids are often strongly non-Newtonian, and significant variations in rheology between batches may occur. We approach the question of how rheology affects mixing by focussing on a the classical case of Taylor-Couette flow, which exhibits a number of instabilities and flow regimes as a function of Reynolds number. We examine Taylor-Couette flow generated for a range of aqueous solutions of xantham gum or corn starch, such that the rheology varies from shear-thinning to shear-thickening. For each case, we measure the power consumption using a torque meter and the flow field using high speed, time-resolved Particle-Image Velocimetry. The mixing characteristics are quantified using a number of Lagrangian and Eulerian approaches, including the coarse grained density method and vortex strength. By comparing these metrics to the power number, we discuss how the mixing efficiency (ratio of mixing effectiveness to power input) varies with the flow index of the fluid.
A Numerical Study of Mesh Adaptivity in Multiphase Flows with Non-Newtonian Fluids
Percival, James; Pavlidis, Dimitrios; Xie, Zhihua; Alberini, Federico; Simmons, Mark; Pain, Christopher; Matar, Omar
2014-11-01
We present an investigation into the computational efficiency benefits of dynamic mesh adaptivity in the numerical simulation of transient multiphase fluid flow problems involving Non-Newtonian fluids. Such fluids appear in a range of industrial applications, from printing inks to toothpastes and introduce new challenges for mesh adaptivity due to the additional ``memory'' of viscoelastic fluids. Nevertheless, the multiscale nature of these flows implies huge potential benefits for a successful implementation. The study is performed using the open source package Fluidity, which couples an unstructured mesh control volume finite element solver for the multiphase Navier-Stokes equations to a dynamic anisotropic mesh adaptivity algorithm, based on estimated solution interpolation error criteria, and conservative mesh-to-mesh interpolation routine. The code is applied to problems involving rheologies ranging from simple Newtonian to shear-thinning to viscoelastic materials and verified against experimental data for various industrial and microfluidic flows. This work was undertaken as part of the EPSRC MEMPHIS programme grant EP/K003976/1.
Borehole guided waves in a non-Newtonian (Maxwell) fluid-saturated porous medium
International Nuclear Information System (INIS)
Zhi-Wen, Cui; Jin-Xia, Liu; Ke-Xie, Wang; Gui-Jin, Yao
2010-01-01
The property of acoustic guided waves generated in a fluid-filled borehole surrounded by a non-Newtonian (Maxwell) fluid-saturated porous formation with a permeable wall is investigated. The influence of non-Newtonian effects on acoustic guided waves such as Stoneley waves, pseudo-Rayleigh waves, flexural waves, and screw waves propagations in a fluid-filled borehole is demonstrated based on the generalized Biot–Tsiklauri model by calculating their velocity dispersion and attenuation coefficients. The corresponding acoustic waveforms illustrate their properties in time domain. The results are also compared with those based on generalized Biot's theory. The results show that the influence of non-Newtonian effect on acoustic guided wave, especially on the attenuation coefficient of guided wave propagation in borehole is noticeable. (classical areas of phenomenology)
Determination of the Köthe-Toeplitz Duals over the Non-Newtonian Complex Field
Directory of Open Access Journals (Sweden)
Uğur Kadak
2014-01-01
Full Text Available The important point to note is that the non-Newtonian calculus is a self-contained system independent of any other system of calculus. Therefore the reader may be surprised to learn that there is a uniform relationship between the corresponding operators of this calculus and the classical calculus. Several basic concepts based on non-Newtonian calculus are presented by Grossman (1983, Grossman and Katz (1978, and Grossman (1979. Following Grossman and Katz, in the present paper, we introduce the sets of bounded, convergent, null series and p-bounded variation of sequences over the complex field C* and prove that these are complete. We propose a quite concrete approach based on the notion of Köthe-Toeplitz duals with respect to the non-Newtonian calculus. Finally, we derive some inclusion relationships between Köthe space and solidness.
Intermediate length scale dynamics of polyisobutylene
International Nuclear Information System (INIS)
Farago, B.; Arbe, A.; Colmenero, J.; Faust, R.; Buchenau, U.; Richter, D.
2002-01-01
We report on a neutron spin echo investigation of the intermediate scale dynamics of polyisobutylene studying both the self-motion and the collective motion. The momentum transfer (Q) dependences of the self-correlation times are found to follow a Q -2/β law in agreement with the picture of Gaussian dynamics. In the full Q range of observation, their temperature dependence is weaker than the rheological shift factor. The same is true for the stress relaxation time as seen in sound wave absorption. The collective times show both temperature dependences; at the structure factor peak, they follow the temperature dependence of the viscosity, but below the peak, one finds the stress relaxation behavior
On Laminar Flow of Non-Newtonian Fluids in Porous Media
Fayed, Hassan E.
2015-10-20
Flow of generalized Newtonian fluids in porous media can be modeled as a bundle of capillary tubes or a pore-scale network. In general, both approaches rely on the solution of Hagen–Poiseuille equation using power law to estimate the variations in the fluid viscosity due to the applied shear rate. Despite the effectiveness and simplicity, power law tends to provide unrealistic values for the effective viscosity especially in the limits of zero and infinite shear rates. Here, instead of using power law, Carreau model (bubbles, drops, and particles in non-Newtonian fluids. Taylor & Francis Group, New York, 2007) is used to determine the effective viscosity as a function of the shear strain rate. Carreau model can predict accurately the variation in the viscosity at all shear rates and provide more accurate solution for the flow physics in a single pore. Using the results for a single pore, normalized Fanning friction coefficient has been calculated and plotted as a function of the newly defined Reynolds number based on pressure gradient. For laminar flow, the variation in the friction coefficient with Reynolds number has been plotted and scaled. It is observed that generalized Newtonian fluid flows show Newtonian nature up to a certain Reynolds number. At high Reynolds number, deviation from the Newtonian behavior is observed. The main contribution of this paper is to present a closed-form solution for the flow in a single pore using Carreau model, which allows for fast evaluation of the relationship between flux and pressure gradient in an arbitrary pore diameter. In this way, we believe that our development will open the perspectives for using Carreau models in pore-network simulations at low computational costs to obtain more accurate prediction for generalized Newtonian fluid flows in porous media.
On Laminar Flow of Non-Newtonian Fluids in Porous Media
Fayed, Hassan E.; Sheikh, Nadeem A.; Iliev, Oleg
2015-01-01
Flow of generalized Newtonian fluids in porous media can be modeled as a bundle of capillary tubes or a pore-scale network. In general, both approaches rely on the solution of Hagen–Poiseuille equation using power law to estimate the variations in the fluid viscosity due to the applied shear rate. Despite the effectiveness and simplicity, power law tends to provide unrealistic values for the effective viscosity especially in the limits of zero and infinite shear rates. Here, instead of using power law, Carreau model (bubbles, drops, and particles in non-Newtonian fluids. Taylor & Francis Group, New York, 2007) is used to determine the effective viscosity as a function of the shear strain rate. Carreau model can predict accurately the variation in the viscosity at all shear rates and provide more accurate solution for the flow physics in a single pore. Using the results for a single pore, normalized Fanning friction coefficient has been calculated and plotted as a function of the newly defined Reynolds number based on pressure gradient. For laminar flow, the variation in the friction coefficient with Reynolds number has been plotted and scaled. It is observed that generalized Newtonian fluid flows show Newtonian nature up to a certain Reynolds number. At high Reynolds number, deviation from the Newtonian behavior is observed. The main contribution of this paper is to present a closed-form solution for the flow in a single pore using Carreau model, which allows for fast evaluation of the relationship between flux and pressure gradient in an arbitrary pore diameter. In this way, we believe that our development will open the perspectives for using Carreau models in pore-network simulations at low computational costs to obtain more accurate prediction for generalized Newtonian fluid flows in porous media.
El-Amin, Mohamed; Salama, Amgad; Sun, Shuyu
2012-01-01
The problem of thermal dispersion effects on unsteady free convection from an isothermal horizontal circular cylinder to a non-Newtonian fluid saturating a porous medium is examined numerically. The Darcy-Brinkman-Forchheimer model is employed to describe the flow field. The thermal diffusivity coefficient has been assumed to be the sum of the molecular diffusivity and the dynamic diffusivity due to mechanical dispersion. The simultaneous development of the momentum and thermal boundary layers are obtained by using finite difference method. The stability conditions are determined for each difference equation. Using an explicit finite difference scheme, solutions at each time-step have been found and then stepped forward in time until reaching steady state solution. Velocity and temperature profiles are shown graphically. It is found that as time approaches infinity, the values of friction factor and heat transfer coefficient approach the steady state values.
El-Amin, Mohamed
2012-06-02
The problem of thermal dispersion effects on unsteady free convection from an isothermal horizontal circular cylinder to a non-Newtonian fluid saturating a porous medium is examined numerically. The Darcy-Brinkman-Forchheimer model is employed to describe the flow field. The thermal diffusivity coefficient has been assumed to be the sum of the molecular diffusivity and the dynamic diffusivity due to mechanical dispersion. The simultaneous development of the momentum and thermal boundary layers are obtained by using finite difference method. The stability conditions are determined for each difference equation. Using an explicit finite difference scheme, solutions at each time-step have been found and then stepped forward in time until reaching steady state solution. Velocity and temperature profiles are shown graphically. It is found that as time approaches infinity, the values of friction factor and heat transfer coefficient approach the steady state values.
Directory of Open Access Journals (Sweden)
Omotayo Omosebi
2015-12-01
This article presents an analytic technique for interpreting pressure falloff tests of non-Newtonian Power-law fluids in wells that are located near boundaries in dual-porosity reservoirs. First, dimensionless pressure solutions are obtained and Stehfest inversion algorithm is used to develop new type curves. Subsequently, long-time analytic solutions are presented and interpretation procedure is proposed using direct synthesis. Two examples, including real field data from a heavy oil reservoir in Colombian eastern plains basin, are used to validate and demonstrate application of this technique. Results agree with conventional type-curve matching procedure. The approach proposed in this study avoids the use of type curves, which is prone to human errors. It provides a better alternative for direct estimation of formation and flow properties from falloff data.
International Nuclear Information System (INIS)
Memon, R.A.; Solangi, M.A.
2013-01-01
The impacts of rotational velocity and inertia on velocity gradients and stresses are addressed under present study. The non-Newtonian behaviour of inelastic rotating flows is predicted by employing Power law model. A numerical model has been developed for mixing flow within a cylindrical vessel along a couple of stirrers. A time marching FEM (Finite Element Method) is employed to predict the required solution. Predicted solutions are presented for minimum to maximum values in terms of contour plots of velocity gradients and shear stresses, over the range. The long term application of this research will be used to improve the design of mixers and processing products. The predicted results are used to generate the capability and are in good agreement with numerical results to the mixer design that will ultimately effect the processing of dough products. (author)
Newtonian and non-newtonian limits of gravitational fields
International Nuclear Information System (INIS)
Koppel', A.A.
1975-01-01
The nonrelativistic limit of the exact stationary axially-symmetric vacuum solution to Einstein equations, which is called the unified (generalized) Kerr-NUT solution, is investigated. Potentials for nonrelativistic gravitational fields, corresponding to this solution, have been calculated. The character of the c→infinity limit (c is the velocity of light) has been shown to depend on the structure of parameters of the Kerr-NUT solution. An example is given that shows the possibility of the existence of a nonrelativistic limit having an absolutely new, non-Newton (vortex) character. From the mathematically proved possibility of the existence of nonrelativistic vortex fields there follow also some implications of a more fundamental character. The Newton limit is commonly supposed to be the only nonrelativistic limit in the Einstein theory. Now there arises a dilemma: either gravitational fields having a non-Newton limit exist in nature and thus the Newton theory does not embrace all gravitational phenomena of nonrelativistic character or in the Newton solutions to the nonrelativistic gravitational equations a certain element of the Einstein theory is revealed that is alien to the true nonrelativistic theory of gravitation. In the former case, one cannot exclude the possibility that owing to a comprehensive analysis of properties, possible sources, etc. the vortex soltions to Einstein equations may prove important in cosmological and astrophysical applications of the general relativity theory. In the latter case, a detailed analysis of the non-Newton-limit solutions will at least enable one to gain a deeper insight into the structure of Einstein equations and their solutions
Newtonian and non-newtonian limits of gravitational fields
Energy Technology Data Exchange (ETDEWEB)
Koppel, A A [Tartuskij Gosudarstvennyj Univ., (USSR)
1975-09-01
The nonrelativistic limit of the exact stationary axially-symmetric vacuum solution to Einstein equations, which is called the unified (generalized) Kerr-NUT solution, is investigated. Potentials for nonrelativistic gravitational fields, corresponding to this solution, have been calculated. The character of the c..-->..infinity limit (c is the velocity of light) has been shown to depend on the structure of parameters of the Kerr-NUT solution. An example is given that shows the possibility of the existence of a nonrelativistic limit having an absolutely new, non-Newton (vortex) character. From the mathematically proved possibility of the existence of nonrelativistic vortex fields there follow also some implications of a more fundamental character. The Newton limit is commonly supposed to be the only nonrelativistic limit in the Einstein theory. Now there arises a dilemma: either gravitational fields having a non-Newton limit exist in nature and thus the Newton theory does not embrace all gravitational phenomena of nonrelativistic character or in the Newton solutions to the nonrelativistic gravitational equations a certain element of the Einstein theory is revealed that is alien to the true nonrelativistic theory of gravitation. In the former case, one cannot exclude the possibility that owing to a comprehensive analysis of properties, possible sources, etc. the vortex soltions to Einstein equations may prove important in cosmological and astrophysical applications of the general relativity theory. In the latter case, a detailed analysis of the non-Newton-limit solutions will at least enable one to gain a deeper insight into the structure of Einstein equations and their solutions.
Non-newtonian deformation of co-based metallic glass at low stresses
Fursova, YV; Khonik, VA; Csach, K; Ocelik, Vaclav
2000-01-01
The results of precision measurements of creep in Co-based metallic glass are presented. It is shown that, in spite of generally accepted concepts, plastic flow at low stresses under intense structural relaxation conditions is of a non-Newtonian type. Consequences of this fact are considered. (C)
MHD free convection flow of a non-Newtonian power-law fluid over ...
African Journals Online (AJOL)
... flow have been presented for various parameters such as Prandtl number, flow behavior index (n), porous plate parameter and magnetic parameter. The local Nusselt number and skin friction coefficient is also presented graphically. Keywords: Magnetohydrodynamic flow; free convection flow; Non-Newtonian power-law
A Lagrangian finite element method for the simulation of flow of non-newtonian liquids
DEFF Research Database (Denmark)
Hassager, Ole; Bisgaard, C
1983-01-01
A Lagrangian method for the simulation of flow of non-Newtonian liquids is implemented. The fluid mechanical equations are formulated in the form of a variational principle, and a discretization is performed by finite elements. The method is applied to the slow of a contravariant convected Maxwell...
Modeling of flow of particles in a non-Newtonian fluid using lattice Boltzmann method
DEFF Research Database (Denmark)
Skocek, Jan; Svec, Oldrich; Spangenberg, Jon
2011-01-01
is necessary. In this contribution, the model at the scale of aggregates is introduced. The conventional lattice Boltzmann method for fluid flow is enriched with the immersed boundary method with direct forcing to simulate the flow of rigid particles in a non- Newtonian liquid. Basic ingredients of the model...
Free surface flow of a suspension of rigid particles in a non-Newtonian fluid
DEFF Research Database (Denmark)
Svec, Oldrich; Skocek, Jan; Stang, Henrik
2012-01-01
A numerical framework capable of predicting the free surface flow of a suspension of rigid particles in a non-Newtonian fluid is described. The framework is a combination of the lattice Boltzmann method for fluid flow, the mass tracking algorithm for free surface representation, the immersed...
Revisiting Newtonian and Non-Newtonian Fluid Mechanics Using Computer Algebra
Knight, D. G.
2006-01-01
This article illustrates how a computer algebra system, such as Maple[R], can assist in the study of theoretical fluid mechanics, for both Newtonian and non-Newtonian fluids. The continuity equation, the stress equations of motion, the Navier-Stokes equations, and various constitutive equations are treated, using a full, but straightforward,…
Binous, Housam
2007-01-01
We study four non-Newtonian fluid mechanics problems using Mathematica[R]. Constitutive equations describing the behavior of power-law, Bingham and Carreau models are recalled. The velocity profile is obtained for the horizontal flow of power-law fluids in pipes and annuli. For the vertical laminar film flow of a Bingham fluid we determine the…
Break-up of a non-Newtonian jet injected downwards in a ...
Indian Academy of Sciences (India)
atomization and spray coating, crop spraying, ink jet printing, printing of polymer transis- tors, and ... particular ones used in printing and coating, the liquids encountered are non-Newtonian. For breakup of ...... In-Press. Sussman M and Pukett E G 2000 A coupled level set and volume-of-fluid method for computing 3D and.
Characterization of the transition of regimes in a non-newtonian fluids in ducts
International Nuclear Information System (INIS)
Santana, C.C.; Ataide, C.H.; Massarani, G.
1983-01-01
By using own experimental data and also those obtained from the literature, the velocities at which transition from laminar to turbulent flows occurs are analysed in time-independent non-newtonian fluids, through the relationship between generalized Reynolds numbers and the rheological fluid parameters. (Author) [pt
Directory of Open Access Journals (Sweden)
Sivakumar Venkatachalam
2011-09-01
Full Text Available Many experiments have been conducted to study the hydrodynamic characteristics of column reactors and loop reactors. In this present work, a novel combined loop airlift fluidized bed reactor was developed to study the effect of superficial gas and liquid velocities, particle diameter, fluid properties on gas holdup by using Newtonian and non-Newtonian liquids. Compressed air was used as gas phase. Water, 5% n-butanol, various concentrations of glycerol (60 and 80% were used as Newtonian liquids, and different concentrations of carboxy methyl cellulose aqueous solutions (0.25, 0.6 and 1.0% were used as non-Newtonian liquids. Different sizes of spheres, Bearl saddles and Raschig rings were used as solid phases. From the experimental results, it was found that the increase in superficial gas velocity increases the gas holdup, but it decreases with increase in superficial liquid velocity and viscosity of liquids. Based on the experimental results a correlation was developed to predict the gas hold-up for Newtonian and non-Newtonian liquids for a wide range of operating conditions at a homogeneous flow regime where the superficial gas velocity is approximately less than 5 cm/s
Naseer, F.
2017-12-01
Contamination of soil and groundwater by adsorbent (persistent) contaminants have been a major concern. Mine tailings, Acid mine drainage, waste disposal areas, active or abandoned surface and underground mines are some major causes of soil and water contamination. It is need of the hour to develop cost effective and efficient remediation techniques for clean-up of soil and aquifers. The objective of this research is to study a methodology of using non-Newtonian fluids for effective remediation of adsorbent contaminants in porous media under non-isothermal flow regimes. The research comprises of three components. Since, non-Newtonian fluid rheology has not been well studied in cold temperatures, the first component of the objective is to expose a non-Newtonian fluid (Guar gum solution) to different temperatures ranging from 30 °C through -5 °C to understand the change in viscosity, shear strength and contact angle of the fluid. Study of the flow characteristic of non-Newtonian fluids in complex porous media has been limited. Hence, the second component of this study will focus on a comparison of flow characteristics of a Newtonian fluid, non-Newtonian fluid and a combination of both fluids in a glass-tube-bundle setup that will act as a synthetic porous media. The study of flow characteristics will also be done for different thermal regimes ranging from -5 °C to 30 °C. The third component of the research will be to compare the effectiveness Guar gum to remediate a surrogate adsorbed contaminant at a certain temperature from the synthetic porous media. Guar gum is biodegradable and hence it is benign to the environment. Through these experiments, the mobility and behavior of Guar gum under varying temperature ranges will be characterized and its effectiveness in removing contaminants from soils will be understood. The impact of temperature change on the fluid and flow stability in the porous medium will be examined in this research. Guar gum is good suspension
Numerical Modeling of Mixing of Chemically Reacting, Non-Newtonian Slurry for Tank Waste Retrieval
International Nuclear Information System (INIS)
Yuen, David A.; Onishi, Yasuo; Rustad, James R.; Michener, Thomas E.; Felmy, Andrew R.; Ten, Arkady A.; Hier, Catherine A.
2000-01-01
Many highly radioactive wastes will be retrieved by installing mixer pumps that inject high-speed jets to stir up the sludge, saltcake, and supernatant liquid in the tank, blending them into a slurry. This slurry will then be pumped out of the tank into a waste treatment facility. Our objectives are to investigate interactions-chemical reactions, waste rheology, and slurry mixing-occurring during the retrieval operation and to provide a scientific basis for the waste retrieval decision-making process. Specific objectives are to: (1) Evaluate numerical modeling of chemically active, non-Newtonian tank waste mixing, coupled with chemical reactions and realistic rheology; (2) Conduct numerical modeling analysis of local and global mixing of non-Newtonian and Newtonian slurries; and (3) Provide the bases to develop a scientifically justifiable, decision-making support tool for the tank waste retrieval operation
Spreading of Non-Newtonian and Newtonian Fluids on a Solid Substrate under Pressure
Energy Technology Data Exchange (ETDEWEB)
Choudhury, Moutushi Dutta; Chandra, Subrata; Nag, Soma; Tarafdar, Sujata [Condensed Matter Physics Research Centre, Physics Department, Jadavpur University, Kolkata 700032 (India); Das, Shantanu, E-mail: mou15july@gmail.com [Reactor Control Division, Bhabha Atomic Research Center, Trombay, Mumbai 400085 (India)
2011-09-15
Strongly non-Newtonian fluids namely, aqueous gels of starch, are shown to exhibit visco-elastic behavior, when subjected to a load. We study arrowroot and potato starch gels. When a droplet of the fluid is sandwiched between two glass plates and compressed, the area of contact between the fluid and plates increases in an oscillatory manner. This is unlike Newtonian fluids, where the area increases monotonically in a similar situation. The periphery moreover, develops an instability, which looks similar to Saffman Taylor fingers. This is not normally seen under compression. The loading history is also found to affect the manner of spreading. We attempt to describe the non-Newtonian nature of the fluid through a visco-elastic model incorporating generalized calculus. This is shown to reproduce qualitatively the oscillatory variation in the surface strain.
Instrumentation to Monitor Transient Periodic Developing Flow in Non-Newtonian Slurries
Energy Technology Data Exchange (ETDEWEB)
Bamberger, Judith A.; Enderlin, Carl W.
2013-11-15
Staff at Pacific Northwest National Laboratory have conducted mixing and mobilization experiments with non-Newtonian slurries that exhibit Bingham plastic and shear thinning behavior and shear strength. This paper describes measurement techniques applied to identify the interface between flowing and stationary regions of non-Newtonian slurries that are subjected to transient, periodic, developing flows. Techniques were developed to identify the boundary between the flowing and stationary regions, time to mix, characteristic velocities of the flow field produced by the symmetrically spaced nozzles, and the velocity of the upwell formed in the center of the tank by the intersection of flow from four symmetrically spaced nozzles that impinge upon the tank floor. Descriptions of the instruments and instrument performance are presented. These techniques were an effective approach to characterize mixing phenomena, determine mixing energy required to fully mobilize vessel contents and to determine mixing times for process evaluation.
Entropy generation in non-Newtonian fluid flow in a slider bearing
Indian Academy of Sciences (India)
In the present study, entropy production in ﬂow ﬁelds due to slider bearings is formulated. The rate of entropy generation is computed for different ﬂuid properties and geometric conﬁgurations of the slider bearing. In order to account for the non-Newtonian effect, a special type of third-grade ﬂuid is considered. It is found that ...
Supersoft Symmetry Energy Encountering Non-Newtonian Gravity in Neutron Stars
International Nuclear Information System (INIS)
Wen Dehua; Li Baoan; Chen Liewen
2009-01-01
Considering the non-Newtonian gravity proposed in grand unification theories, we show that the stability and observed global properties of neutron stars cannot rule out the supersoft nuclear symmetry energies at suprasaturation densities. The degree of possible violation of the inverse-square law of gravity in neutron stars is estimated using an equation of state of neutron-rich nuclear matter consistent with the available terrestrial laboratory data.
International Nuclear Information System (INIS)
Makinde, O.D.
2005-10-01
In this paper, the first and second law of thermodynamics are employed in order to study the inherent irreversibility for a gravity driven non-Newtonian Ostwald-de Waele power law liquid film along an inclined isothermal plate. Based on some simplified assumptions, the governing equations are obtained and solved analytically. Expressions for fluid velocity, temperature, volumetric entropy generation numbers, irreversibility distribution ratio and the Bejan number are also determined. (author)
Change in the flow curves of non-Newtonian oils due to a magnetic field
International Nuclear Information System (INIS)
Veliev, F.G.
1979-01-01
The effect of a variable magnetic field on the rheological properties of non-Newtonian fluids is evaluated. Bituminous pitch oils were analyzed by recording the flow curves Q.Q(Δp) - the dependence of the volumetric flow rate on the pressure gradient - with and without a field. The results obtained indicate that variable magnetic fields can produce obvious changes in the rheological properties of bituminous pitch oils, although they are nonmagnetoactive and practically electrically nonconducting
Steady flow of non-Newtonian fluids - monotonicity methods in generalized orlicz spaces
Czech Academy of Sciences Publication Activity Database
Wróblewska, Aneta
2010-01-01
Roč. 72, č. 11 (2010), s. 4136-4147 ISSN 0362-546X Institutional research plan: CEZ:AV0Z10190503 Keywords : non-Newtonian fluid * Orlicz spaces * modular convergence of symmetric gradients * general ized Minty method * smart fluids Subject RIV: BA - General Mathematics Impact factor: 1.279, year: 2010 http://www.sciencedirect.com/science/article/pii/S0362546X10000568
Steady flow of non-Newtonian fluids - monotonicity methods in generalized orlicz spaces
Czech Academy of Sciences Publication Activity Database
Wróblewska, Aneta
2010-01-01
Roč. 72, č. 11 (2010), s. 4136-4147 ISSN 0362-546X Institutional research plan: CEZ:AV0Z10190503 Keywords : non-Newtonian fluid * Orlicz spaces * modular convergence of symmetric gradients * generalized Minty method * smart fluids Subject RIV: BA - General Mathematics Impact factor: 1.279, year: 2010 http://www.sciencedirect.com/science/article/pii/S0362546X10000568
Conceptual coherence of non-Newtonian worldviews in Force Concept Inventory data
Directory of Open Access Journals (Sweden)
Terry F. Scott
2017-05-01
Full Text Available The Force Concept Inventory is one of the most popular and most analyzed multiple-choice concept tests used to investigate students’ understanding of Newtonian mechanics. The correct answers poll a set of underlying Newtonian concepts and the coherence of these underlying concepts has been found in the data. However, this inventory was constructed after several years of research into the common preconceptions held by students and using these preconceptions as distractors in the questions. Their sole purpose is to deflect non-Newtonian candidates away from the correct answer. Alternatively, one can argue that the responses could also be treated as polling these preconceptions. In this paper we shift the emphasis of the analysis away from the correlation structure of the correct answers and look at the latent traits underlying the incorrect responses. Our analysis models the data employing exploratory factor analysis, which uses regularities in the data to suggest the existence of underlying structures in the cognitive processing of the students. This analysis allows us to determine whether the data support the claim that there are alternate non-Newtonian worldviews on which students’ incorrect responses are based. The existence of such worldviews, and their coherence, could explain the resilience of non-Newtonian preconceptions and would have significant implications to the design of instruction methods. We find that there are indeed coherent alternate conceptions of the world which can be categorized using the results of the research that led to the construction of the Force Concept Inventory.
Are Non-Newtonian Effects Important in Hemodynamic Simulations of Patients With Autogenous Fistula?
Javid Mahmoudzadeh Akherat, S M; Cassel, Kevin; Boghosian, Michael; Dhar, Promila; Hammes, Mary
2017-04-01
Given the current emphasis on accurate computational fluid dynamics (CFD) modeling of cardiovascular flows, which incorporates realistic blood vessel geometries and cardiac waveforms, it is necessary to revisit the conventional wisdom regarding the influences of non-Newtonian effects. In this study, patient-specific reconstructed 3D geometries, whole blood viscosity data, and venous pulses postdialysis access surgery are used as the basis for the hemodynamic simulations of renal failure patients with native fistula access. Rheological analysis of the viscometry data initially suggested that the correct choice of constitutive relations to capture the non-Newtonian behavior of blood is important because the end-stage renal disease (ESRD) patient cohort under observation experience drastic variations in hematocrit (Hct) levels and whole blood viscosity throughout the hemodialysis treatment. For this purpose, various constitutive relations have been tested and implemented in CFD practice, namely Quemada and Casson. Because of the specific interest in neointimal hyperplasia and the onset of stenosis in this study, particular attention is placed on differences in nonhomeostatic wall shear stress (WSS) as that drives the venous adaptation process that leads to venous geometric evolution over time in ESRD patients. Surprisingly, the CFD results exhibit no major differences in the flow field and general flow characteristics of a non-Newtonian simulation and a corresponding identical Newtonian counterpart. It is found that the vein's geometric features and the dialysis-induced flow rate have far greater influence on the WSS distribution within the numerical domain.
External gear pumps operating with non-Newtonian fluids: Modelling and experimental validation
Rituraj, Fnu; Vacca, Andrea
2018-06-01
External Gear Pumps are used in various industries to pump non-Newtonian viscoelastic fluids like plastics, paints, inks, etc. For both design and analysis purposes, it is often a matter of interest to understand the features of the displacing action realized by meshing of the gears and the description of the behavior of the leakages for this kind of pumps. However, very limited work can be found in literature about methodologies suitable to model such phenomena. This article describes the technique of modelling external gear pumps that operate with non-Newtonian fluids. In particular, it explains how the displacing action of the unit can be modelled using a lumped parameter approach which involves dividing fluid domain into several control volumes and internal flow connections. This work is built upon the HYGESim simulation tool, conceived by the authors' research team in the last decade, which is for the first time extended for the simulation of non-Newtonian fluids. The article also describes several comparisons between simulation results and experimental data obtained from numerous experiments performed for validation of the presented methodology. Finally, operation of external gear pump with fluids having different viscosity characteristics is discussed.
Are Non-Newtonian Effects Important in Hemodynamic Simulations of Patients With Autogenous Fistula?
Javid Mahmoudzadeh Akherat, S. M.; Cassel, Kevin; Boghosian, Michael; Dhar, Promila; Hammes, Mary
2017-01-01
Given the current emphasis on accurate computational fluid dynamics (CFD) modeling of cardiovascular flows, which incorporates realistic blood vessel geometries and cardiac waveforms, it is necessary to revisit the conventional wisdom regarding the influences of non-Newtonian effects. In this study, patient-specific reconstructed 3D geometries, whole blood viscosity data, and venous pulses postdialysis access surgery are used as the basis for the hemodynamic simulations of renal failure patients with native fistula access. Rheological analysis of the viscometry data initially suggested that the correct choice of constitutive relations to capture the non-Newtonian behavior of blood is important because the end-stage renal disease (ESRD) patient cohort under observation experience drastic variations in hematocrit (Hct) levels and whole blood viscosity throughout the hemodialysis treatment. For this purpose, various constitutive relations have been tested and implemented in CFD practice, namely Quemada and Casson. Because of the specific interest in neointimal hyperplasia and the onset of stenosis in this study, particular attention is placed on differences in nonhomeostatic wall shear stress (WSS) as that drives the venous adaptation process that leads to venous geometric evolution over time in ESRD patients. Surprisingly, the CFD results exhibit no major differences in the flow field and general flow characteristics of a non-Newtonian simulation and a corresponding identical Newtonian counterpart. It is found that the vein's geometric features and the dialysis-induced flow rate have far greater influence on the WSS distribution within the numerical domain. PMID:28249082
Slip-flow and heat transfer of a non-newtonian nanofluid in a microtube.
Niu, Jun; Fu, Ceji; Tan, Wenchang
2012-01-01
The slip-flow and heat transfer of a non-Newtonian nanofluid in a microtube is theoretically studied. The power-law rheology is adopted to describe the non-Newtonian characteristics of the flow, in which the fluid consistency coefficient and the flow behavior index depend on the nanoparticle volume fraction. The velocity profile, volumetric flow rate and local Nusselt number are calculated for different values of nanoparticle volume fraction and slip length. The results show that the influence of nanoparticle volume fraction on the flow of the nanofluid depends on the pressure gradient, which is quite different from that of the Newtonian nanofluid. Increase of the nanoparticle volume fraction has the effect to impede the flow at a small pressure gradient, but it changes to facilitate the flow when the pressure gradient is large enough. This remarkable phenomenon is observed when the tube radius shrinks to micrometer scale. On the other hand, we find that increase of the slip length always results in larger flow rate of the nanofluid. Furthermore, the heat transfer rate of the nanofluid in the microtube can be enhanced due to the non-Newtonian rheology and slip boundary effects. The thermally fully developed heat transfer rate under constant wall temperature and constant heat flux boundary conditions is also compared.
A DNS Investigation of Non-Newtonian Turbulent Open Channel Flow
Guang, Raymond; Rudman, Murray; Chryss, Andrew; Slatter, Paul; Bhattacharya, Sati
2010-06-01
The flow of non-Newtonian fluids in open channels has great significance in many industrial settings from water treatment to mine waste disposal. The turbulent behaviour during transportation of these materials is of interest for many reasons, one of which is keeping settleable particles in suspension. The mechanism governing particle transport in turbulent flow has been studied in the past, but is not well understood. A better understanding of the mechanism operating in the turbulent flow of non-Newtonian suspensions in open channel would lead to improved design of many of the systems used in the mining and mineral processing industries. The objective of this paper is to introduce our work on the Direct Numerical Simulation of turbulent flow of non-Newtonian fluids in an open channel. The numerical method is based on spectral element/Fourier formulation. The flow simulation of a Herschel-Bulkley fluid agrees qualitatively with experimental results. The simulation results over-predict the flow velocity by approximately 15% for the cases considered, although the source of the discrepancy is difficult to ascertain. The effect of variation in yield stress and assumed flow depth are investigated and used to assess the sensitivity of the flow to these physical parameters. This methodology is seen to be useful in designing and optimising the transport of slurries in open channels.
Directory of Open Access Journals (Sweden)
J.I. Orisaleye
2018-04-01
Full Text Available Extruders have found application in the food, polymer and pharmaceutical industries. Rheological characteristics of materials are important in the specification of design parameters of screw extruders. Biopolymers, which consist of proteins, nucleic acids and polysaccharides, are shear-thinning (pseudoplastic within normal operating ranges. However, analytical models to predict and design screw extruders for non-Newtonian pseudoplastic materials are rare. In this study, an analytical model suitable to design a screw extruder for slightly non-Newtonian materials was developed. The model was used to predict the performance of the screw extruder while processing materials with power law indices slightly deviating from unity (the Newtonian case. Using non-dimensional analysis, the effects of design and operational parameters were investigated. Expressions to determine the optimum channel depth and helix angle were also derived. The model is capable of predicting the performance of the screw extruder within the range of power law indices considered (1/2⩽n⩽1. The power law index influences the choice of optimum channel depth and helix angle of the screw extruder. Keywords: Screw extruder, Slightly non-Newtonian, Shear-thinning, Pseudoplastic, Biopolymer, Power law
Directory of Open Access Journals (Sweden)
M.A. Bosse
2001-03-01
Full Text Available The problem of the effect of Joule heating generation on the hydrodynamic profile and the solute transport found in electrophoretic devices is addressed in this article. The research is focused on the following two problems: The first one is centered around the effect of Joule heating on the hydrodynamic velocity profile and it is referred to as "the carrier fluid problem." The other one is related to the effect of Joule heating on the solute transport inside electrophoretic cells and it is referred to as "the solute problem". The hydrodynamic aspects were studied first to yield the velocity profiles required for analysis of the solute transport problem. The velocity profile obtained in this study is analytical and the results are valid for non-Newtonian fluids carriers. To this end, the power-law model was used to study the effect of the rheology of the material in conjunction with the effect of Joule heating generation inside batch electrophoretic devices. This aspect of the research was then effectively used to study the effect of Joule heating generation on the motion of solutes (such as macromolecules under the influence of non-Newtonian carriers. This aspect of the study was performed using an area-averaging approach that yielded analytical results for the effective diffusivity of the device.
International Nuclear Information System (INIS)
Moh, Jeong Hah; Cho, Y. I.
2014-01-01
This paper presents the theoretical analysis of a flow driven by surface tension and gravity in an inclined circular tube. A governing equation is developed for describing the displacement of a non-Newtonian fluid(Power-law model) that continuously flows into a circular tube owing to surface tension, which represents a second-order, nonlinear, non-homogeneous, and ordinary differential form. It was found that quantitatively, the theoretical predictions of the governing equation were in excellent agreement with the solutions of the equation for horizontal tubes and the past experimental data. In addition, the predictions compared very well with the results of the force balance equation for steady
Nesvizhevsky, V V; Protasov, K V
2005-01-01
An upper limit to non-Newtonian attractive forces is obtained from the measurement of quantum states of neutrons in the Earth's gravitational field. This limit improves the existing constraints in the nanometer range.
Characteristics of gas-liquid dynamics in operation of oil fields producing non-Newtonian crude oils
Energy Technology Data Exchange (ETDEWEB)
Mirzadzhanzade, A Kh; Khasaev, A M; Gurbanov, R S; Akhmedov, Z M
1968-08-01
Experimental studies have shown that crude oils from Azerbaidzhan, Uzbekistan, Tataria, Kazakhstan and other areas have anomalous properties under reservoir conditions. Such crude oils are non-Newtonian and (1) obey Darcys Law at low velocities; (2) obey an exponential law at higher velocities; and (3) obey a modified Darcys Law at most velocities. A discussion is given of (1) flow of non-Newtonian crude oils together with gas or water; (2) flow of non-Newtonian crude oils in well tubing; (3) behavior of wells producing non-Newtonian crude oils; and (4) pumping of non-Newtonian oils in wells. Experiments have shown that a visco-plastic liquid does not fill pump inlets completely; as the diameter of the pump inlet decreases so also does the degree of liquid filling. A statistical analysis of production data from 160 fields with Newtonian oil and 129 fields with non- Newtonian oil has shown that much higher production is obtained from fields with Newtonian crude oils.
MASS TRANSFER COEFFICIENTS FOR A NON-NEWTONIAN FLUID AND WATER WITH AND WITHOUT ANTI-FOAM AGENTS
Energy Technology Data Exchange (ETDEWEB)
Leishear, R.
2009-09-09
Mass transfer rates were measured in a large scale system, which consisted of an 8.4 meter tall by 0.76 meter diameter column containing one of three fluids: water with an anti-foam agent, water without an anti-foam agent, and AZ101 simulant, which simulated a non-Newtonian nuclear waste. The testing contributed to the evaluation of large scale mass transfer of hydrogen in nuclear waste tanks. Due to its radioactivity, the waste was chemically simulated, and due to flammability concerns oxygen was used in lieu of hydrogen. Different liquids were used to better understand the mass transfer processes, where each of the fluids was saturated with oxygen, and the oxygen was then removed from solution as air bubbled up, or sparged, through the solution from the bottom of the column. Air sparging was supplied by a single tube which was co-axial to the column, the decrease in oxygen concentration was recorded, and oxygen measurements were then used to determine the mass transfer coefficients to describe the rate of oxygen transfer from solution. Superficial, average, sparging velocities of 2, 5, and 10 mm/second were applied to each of the liquids at three different column fill levels, and mass transfer coefficient test results are presented here for combinations of superficial velocities and fluid levels.
MASS TRANSFER COEFFICIENTS FOR A NON-NEWTONIAN FLUID AND WATER WITH AND WITHOUT ANTI-FOAM AGENTS
International Nuclear Information System (INIS)
Leishear, R.
2009-01-01
Mass transfer rates were measured in a large scale system, which consisted of an 8.4 meter tall by 0.76 meter diameter column containing one of three fluids: water with an anti-foam agent, water without an anti-foam agent, and AZ101 simulant, which simulated a non-Newtonian nuclear waste. The testing contributed to the evaluation of large scale mass transfer of hydrogen in nuclear waste tanks. Due to its radioactivity, the waste was chemically simulated, and due to flammability concerns oxygen was used in lieu of hydrogen. Different liquids were used to better understand the mass transfer processes, where each of the fluids was saturated with oxygen, and the oxygen was then removed from solution as air bubbled up, or sparged, through the solution from the bottom of the column. Air sparging was supplied by a single tube which was co-axial to the column, the decrease in oxygen concentration was recorded, and oxygen measurements were then used to determine the mass transfer coefficients to describe the rate of oxygen transfer from solution. Superficial, average, sparging velocities of 2, 5, and 10 mm/second were applied to each of the liquids at three different column fill levels, and mass transfer coefficient test results are presented here for combinations of superficial velocities and fluid levels
Downhole Temperature Modeling for Non-Newtonian Fluids in ERD Wells
Directory of Open Access Journals (Sweden)
Dan Sui
2018-04-01
Full Text Available Having precise information of fluids' temperatures is a critical process during planning of drilling operations, especially for extended reach drilling (ERD. The objective of this paper is to develop an accurate temperature model that can precisely calculate wellbore temperature distributions. An established semi-transient temperature model for vertical wellbores is extended and improved to include deviated wellbores and more realistic scenarios using non-Newtonian fluids. The temperature model is derived based on an energy balance between the formation and the wellbore. Heat transfer is considered steady-state in the wellbore and transient in the formation through the utilization of a formation cooling effect. In this paper, the energy balance is enhanced by implementing heat generation from the drill bit friction and contact friction force caused by drillpipe rotation. A non-linear geothermal gradient as a function of wellbore inclination, is also introduced to extend the model to deviated wellbores. Additionally, the model is improved by considering temperature dependent drilling fluid transport and thermal properties. Transport properties such as viscosity and density are obtained by lab measurements, which allows for investigation of the effect of non-Newtonian fluid behavior on the heat transfer. Furthermore, applying a non-Newtonian pressure loss model enables an opportunity to evaluate the impact of viscous forces on fluid properties and thus the overall heat transfer. Results from sensitivity analysis of both drilling fluid properties and other relevant parameters will be presented. The main application area of this model is related to optimization of drilling fluid, hydraulics, and wellbore design parameters, ultimately leading to safe and cost efficient operations.
Soulis, Johannes V; Fytanidis, Dimitrios K; Lampri, Olga P; Giannoglou, George D
2016-04-01
The temporal variation of the hemodynamic mechanical parameters during cardiac pulse wave is considered as an important atherogenic factor. Applying non-Newtonian blood molecular viscosity simulation is crucial for hemodynamic analysis. Understanding low density lipoprotein (LDL) distribution in relation to flow parameters will possibly spot the prone to atherosclerosis aorta regions. The biomechanical parameters tested were averaged wall shear stress (AWSS), oscillatory shear index (OSI) and relative residence time (RRT) in relation to the LDL concentration. Four non-Newtonian molecular viscosity models and the Newtonian one were tested for the normal human aorta under oscillating flow. The analysis was performed via computational fluid dynamic. Tested viscosity blood flow models for the biomechanical parameters yield a consistent aorta pattern. High OSI and low AWSS develop at the concave aorta regions. This is most noticeable in downstream flow region of the left subclavian artery and at concave ascending aorta. Concave aorta regions exhibit high RRT and elevated LDL. For the concave aorta site, the peak LDL value is 35.0% higher than its entrance value. For the convex site, it is 18.0%. High LDL endothelium regions located at the aorta concave site are well predicted with high RRT. We are in favor of using the non-Newtonian power law model for analysis. It satisfactorily approximates the molecular viscosity, WSS, OSI, RRT and LDL distribution. Concave regions are mostly prone to atherosclerosis. The flow biomechanical factor RRT is a relatively useful tool for identifying the localization of the atheromatic plaques of the normal human aorta.
Non-Newtonian Hele-Shaw Flow and the Saffman-Taylor Instability
International Nuclear Information System (INIS)
Kondic, L.; Shelley, M.J.; Palffy-Muhoray, P.
1998-01-01
We explore the Saffman-Taylor instability of a gas bubble expanding into a shear thinning liquid in a radial Hele-Shaw cell. Using Darcy close-quote s law generalized for non-Newtonian fluids, we perform simulations of the full dynamical problem. The simulations show that shear thinning significantly influences the developing interfacial patterns. Shear thinning can suppress tip splitting, and produce fingers which oscillate during growth and shed side branches. Emergent length scales show reasonable agreement with a general linear stability analysis. copyright 1998 The American Physical Society
Non-Newtonian behavior and molecular structure of Cooee bitumen under shear flow
DEFF Research Database (Denmark)
Lemarchand, Claire; Bailey, Nicholas; Daivis, Peter
2015-01-01
The rheology and molecular structure of a model bitumen (Cooee bitumen) under shear are investigated in the non-Newtonian regime using non-equilibrium molecular dynamics simulations. The shear viscosity, normal stress differences, and pressure of the bitumen mixture are computed at different shear...... rates and different temperatures. The model bitumen is shown to be a shear-thinning fluid at all temperatures. In addition, the Cooee model is able to reproduce experimental results showing the formation of nanoaggregates composed of stacks of flat aromatic molecules in bitumen. These nanoaggregates...
Directory of Open Access Journals (Sweden)
Jamshid M. Nouri
2008-03-01
Full Text Available Mean and rms velocity characteristics of two Newtonian flows at Reynolds numbers of 12,800 (glycerin solution and 48,000 (water and of a non-Newtonian flow (0.2% CMC solution, at a power number similar to the Newtonian glycerin flow in a mixing vessel stirred by a 60° pitched blade impeller have been measured by laser Doppler velocimetry (LDV. The velocity measurements, resolved over 360° and 1.08° of impeller rotation, showed that the mean flow of the two power number matched glycerin and CMC flows were similar to within 3% of the impeller tip velocity and the turbulence intensities generally lower in the CMC flow by up to 5% of the tip velocity. The calculated mean flow quantities showed similar discharge coefficient and pumping efficiency in all three flows and similar strain rate between the two power number matched glycerin and CMC flows; the strain rate of the higher Reynolds number Newtonian flow was found to be slightly higher. The energy balance around the impeller indicated that the CMC flow dissipated up to 9% more of the total input power and converted 7% less into the turbulence compared to the glycerin flow with the same power input which could lead to less effective mixing processes where the micro-mixing is important.
Khan, Zeeshan; Khan, Ilyas; Ullah, Murad; Tlili, I.
2018-06-01
In this work, we discuss the unsteady flow of non-Newtonian fluid with the properties of heat source/sink in the presence of thermal radiation moving through a binary mixture embedded in a porous medium. The basic equations of motion including continuity, momentum, energy and concentration are simplified and solved analytically by using Homotopy Analysis Method (HAM). The energy and concentration fields are coupled with Dankohler and Schmidt numbers. By applying suitable transformation, the coupled nonlinear partial differential equations are converted to couple ordinary differential equations. The effect of physical parameters involved in the solutions of velocity, temperature and concentration profiles are discussed by assign numerical values and results obtained shows that the velocity, temperature and concentration profiles are influenced appreciably by the radiation parameter, Prandtl number, suction/injection parameter, reaction order index, solutal Grashof number and the thermal Grashof. It is observed that the non-Newtonian parameter H leads to an increase in the boundary layer thickness. It was established that the Prandtl number decreases thee thermal boundary layer thickness which helps in maintaining system temperature of the fluid flow. It is observed that the temperature profiles higher for heat source parameter and lower for heat sink parameter throughout the boundary layer. Fromm this simulation it is analyzed that an increase in the Schmidt number decreases the concentration boundary layer thickness. Additionally, for the sake of comparison numerical method (ND-Solve) and Adomian Decomposition Method are also applied and good agreement is found.
CFD simulation of gas and non-Newtonian fluid two-phase flow in anaerobic digesters.
Wu, Binxin
2010-07-01
This paper presents an Eulerian multiphase flow model that characterizes gas mixing in anaerobic digesters. In the model development, liquid manure is assumed to be water or a non-Newtonian fluid that is dependent on total solids (TS) concentration. To establish the appropriate models for different TS levels, twelve turbulence models are evaluated by comparing the frictional pressure drops of gas and non-Newtonian fluid two-phase flow in a horizontal pipe obtained from computational fluid dynamics (CFD) with those from a correlation analysis. The commercial CFD software, Fluent12.0, is employed to simulate the multiphase flow in the digesters. The simulation results in a small-sized digester are validated against the experimental data from literature. Comparison of two gas mixing designs in a medium-sized digester demonstrates that mixing intensity is insensitive to the TS in confined gas mixing, whereas there are significant decreases with increases of TS in unconfined gas mixing. Moreover, comparison of three mixing methods indicates that gas mixing is more efficient than mixing by pumped circulation while it is less efficient than mechanical mixing.
Physically based model for extracting dual permeability parameters using non-Newtonian fluids
Abou Najm, M. R.; Basset, C.; Stewart, R. D.; Hauswirth, S.
2017-12-01
Dual permeability models are effective for the assessment of flow and transport in structured soils with two dominant structures. The major challenge to those models remains in the ability to determine appropriate and unique parameters through affordable, simple, and non-destructive methods. This study investigates the use of water and a non-Newtonian fluid in saturated flow experiments to derive physically-based parameters required for improved flow predictions using dual permeability models. We assess the ability of these two fluids to accurately estimate the representative pore sizes in dual-domain soils, by determining the effective pore sizes of macropores and micropores. We developed two sub-models that solve for the effective macropore size assuming either cylindrical (e.g., biological pores) or planar (e.g., shrinkage cracks and fissures) pore geometries, with the micropores assumed to be represented by a single effective radius. Furthermore, the model solves for the percent contribution to flow (wi) corresponding to the representative macro and micro pores. A user-friendly solver was developed to numerically solve the system of equations, given that relevant non-Newtonian viscosity models lack forms conducive to analytical integration. The proposed dual-permeability model is a unique attempt to derive physically based parameters capable of measuring dual hydraulic conductivities, and therefore may be useful in reducing parameter uncertainty and improving hydrologic model predictions.
CFD-PBM Coupled Simulation of an Airlift Reactor with Non-Newtonian Fluid
Directory of Open Access Journals (Sweden)
Han Mei
2017-09-01
Full Text Available Hydrodynamics of an AirLift Reactor (ALR with tap water and non-Newtonian fluid was studied experimentally and by numerical simulations. The Population Balance Model (PBM with multiple breakup and coalescence mechanisms was used to describe bubble size characteristics in the ALR. The interphase forces for closing the two-fluid model were formulated by considering the effect of Bubble Size Distribution (BSD. The BSD in the ALR obtained from the coupled Computational Fluid Dynamics (CFD-PBM model was validated against results from digital imaging measurements. The simulated velocity fields of both the gas and liquid phases were compared to measured fields obtained with Particle Image Velocimetry (PIV. The simulated results show different velocity field profile features at the top of the ALR between tap water and non-Newtonian fluid, which are in agreement with experiments. In addition, good agreement between simulations and experiments was obtained in terms of overall gas holdup and bubble Sauter mean diameter.
Directory of Open Access Journals (Sweden)
M. Rahimi-Gorji
2015-06-01
Full Text Available An analytical investigation is applied for unsteady motion of a rigid spherical particle in a quiescent shear-thinning power-law fluid. The results were compared with those obtained from Collocation Method (CM and the established Numerical Method (Fourth order Runge–Kutta scheme. It was shown that CM gave accurate results. Collocation Method (CM and Numerical Method are used to solve the present problem. We obtained that the CM which was used to solve such nonlinear differential equation with fractional power is simpler and more accurate than series method such as HPM which was used in some previous works by others but the new method named Akbari-Ganji’s Method (AGM is an accurate and simple method which is slower than CM for solving such problems. The terminal settling velocity—that is the velocity at which the net forces on a falling particle eliminate—for three different spherical particles (made of plastic, glass and steel and three flow behavior index n, in three sets of power-law non-Newtonian fluids was investigated, based on polynomial solution (CM. Analytical results obtained indicated that the time of reaching the terminal velocity in a falling procedure is significantly increased with growing of the particle size that validated with Numerical Method. Further, with approaching flow behavior to Newtonian behavior from shear-thinning properties of flow (n → 1, the transient time to achieving the terminal settling velocity is decreased.
Tazraei, Pedram; Riasi, Alireza; Takabi, Behrouz
2015-06-01
This work investigates a two dimensional numerical analysis of blood hammer through the posterior cerebral artery. The non-Newtonian and usual Newtonian blood models are compared in the case of blood hammer through the posterior cerebral artery to quantify the differences between the models. In this way, a validated CFD simulation is used to study non-Newtonian shear-thinning effects of blood. The governing equations for the modeling of two-dimensional transient flow are solved using a combination of characteristics and central finite difference methods, respectively for the hyperbolic and parabolic parts. Herein, the non-Newtonian viscosity characteristic of blood is incorporated by using the Carreau model. To convert the nonlinear terms available in the characteristics equation into the linear ones, the Newton-Kantorovich method is implemented. The verification and validation of the numerical results are carried out in detail. Hemodynamic characteristics of blood hammer through the posterior cerebral artery are derived with both the Newtonian and non-Newtonian models, and the results are meticulously compared and discussed. The results show that when blood hammer occurs, the non-Newtonian properties greatly influence the velocity and shear stress profiles. At the early stages of blood hammer, there is a 64% difference between magnitudes of wall shear stress in these two models, and the magnitude of the wall shear stress for the shear-thinning blood flow is lower than the Newtonian one. Copyright © 2015 Elsevier Inc. All rights reserved.
A new 3D immersed boundary method for non-Newtonian fluid-structure-interaction with application
Zhu, Luoding
2017-11-01
Motivated by fluid-structure-interaction (FSI) phenomena in life sciences (e.g., motions of sperm and cytoskeleton in complex fluids), we introduce a new immersed boundary method for FSI problems involving non-Newtonian fluids in three dimensions. The non-Newtonian fluids are modelled by the FENE-P model (including the Oldroyd-B model as an especial case) and numerically solved by a lattice Boltzmann scheme (the D3Q7 model). The fluid flow is modelled by the lattice Boltzmann equations and numerically solved by the D3Q19 model. The deformable structure and the fluid-structure-interaction are handled by the immersed boundary method. As an application, we study a FSI toy problem - interaction of an elastic plate (flapped at its leading edge and restricted nowhere else) with a non-Newtonian fluid in a 3D flow. Thanks to the support of NSF-DMS support under research Grant 1522554.
Possible evidence for non-Newtonian gravity in the Greenland ice gap
International Nuclear Information System (INIS)
Ander, M.E.
1988-01-01
An Airy-type geophysical experiment was conducted down a 2 km deep hole in the Greenland ice cap in order to test for possible violations of Newton's inverse square law by making gravity measurements over a range of 213 m to 1460 m. A significant departure from Newtonian gravity was observed. This result can be explained by the existence of an attractive non-Newtonian component of gravity with a strength of about 3.4% that of Newtonian gravity at a scale of 1460 m. Unfortunately, we cannot completely, unambiguously attribute it to a breakdown of Newtonian gravity because we have shown that lateral density variations in the bedrock beneath the ice can cause such apparent departures. If such variations existed, they would have to be rather unusual but certainly no impossible. 8 refs
Simulation of forced convection in non-Newtonian fluid through sandstones
Gokhale, M. Y.; Fernandes, Ignatius
2017-11-01
Numerical simulation is carried out to study forced convection in non-Newtonian fluids flowing through sandstones. Simulation is carried out using lattice Boltzmann method (LBM) for both shear-thinning and shear-thickening, by varying the power law index from 0.5 to 1.5 in Carreau-Yasuda model. Parameters involved in LBM and Carreau model are identified to achieve numerical convergence. Permeability and porosity are varied in the range of 10-10-10-6 and 0.1-0.7, respectively, to match actual geometrical properties of sandstone. Numerical technology is validated by establishing Darcy's law by plotting the graph between velocity and pressure gradient. Consequently, investigation is carried out to study the influence of material properties of porous media on flow properties such as velocity profiles, temperature profiles, and Nusselt number.
Development of a new continuous process for mixing of complex non-Newtonian fluids
Migliozzi, Simona; Mazzei, Luca; Sochon, Bob; Angeli, Panagiota; Thames Multiphase Team; Coral Project Collaboration
2017-11-01
Design of new continuous mixing operations poses many challenges, especially when dealing with highly viscous non-Newtonian fluids. Knowledge of complex rheological behaviour of the working mixture is crucial for development of an efficient process. In this work, we investigate the mixing performance of two different static mixers and the effects of the mixture rheology on the manufacturing of novel non-aqueous-based oral care products using experimental and computational fluid dynamic methods. The two liquid phases employed, i.e. a carbomer suspension in polyethylene glycol and glycerol, start to form a gel when they mix. We studied the structure evolution of the liquid mixture using time-resolved rheometry and we obtained viscosity rheograms at different phase ratios from pressure drop measurements in a customized mini-channel. The numerical results and rheological model were validated with experimental measurements carried out in a specifically designed setup. EPSRS-CORAL.
Shear-induced structural transitions in Newtonian non-Newtonian two-phase flow
Cristobal, G.; Rouch, J.; Colin, A.; Panizza, P.
2000-09-01
We show the existence under shear flow of steady states in a two-phase region of a brine-surfactant system in which lyotropic dilute lamellar (non-Newtonian) and sponge (Newtonian) phases are coexisting. At high shear rates and low sponge phase-volume fractions, we report on the existence of a dynamic transition corresponding to the formation of a colloidal crystal of multilamellar vesicles (or ``onions'') immersed in the sponge matrix. As the sponge phase-volume fraction increases, this transition exhibits a hysteresis loop leading to a structural bistability of the two-phase flow. Contrary to single phase lamellar systems where it is always 100%, the onion volume fraction can be monitored continuously from 0 to 100 %.
Force effects on rotor of squeeze film damper using Newtonian and non-Newtonian fluid
Dominik, Šedivý; Petr, Ferfecki; Simona, Fialová
2017-09-01
This article presents the evaluation of force effects on rotor of squeeze film damper. Rotor is eccentric placed and its motion is translate-circular. The amplitude of rotor motion is smaller than its initial eccentricity. The force effects are calculated from pressure and viscous forces which were gained by using computational modeling. Two types of fluid were considered as filling of damper. First type of fluid is Newtonian (has constant viscosity) and second type is magnetorheological fluid (does not have constant viscosity). Viscosity of non-Newtonian fluid is given using Bingham rheology model. Yield stress is a function of magnetic induction which is described by many variables. The most important variables of magnetic induction are electric current and gap width which is between rotor and stator. Comparison of application two given types of fluids is shown in results.
Motion of Charged Suspended Particle in a Non-Newtonian Fluid between Two Long Parallel Plated
International Nuclear Information System (INIS)
Abd-El Khalek, M.M.
1998-01-01
The motion of charged suspended particle in a non-Newtonian fluid between two long parallel plates is discussed. The equation of motion of a suspended particle was suggested by Closkin. The equations of motion are reduced to ordinary differential equations by similarity transformations and solved numerically by using the Runge-Kutta method. The trajectories of particles are calculated by integrating the equation of motion of a single particle. The present simulation requires some empirical parameters concerning the collision of the particles with the wall. The effects of solid particles on flow properties are discussed. Some typical results for both fluid and particle phases and density distributions of the particles are presented graphically
Calculation of the Pitot tube correction factor for Newtonian and non-Newtonian fluids.
Etemad, S Gh; Thibault, J; Hashemabadi, S H
2003-10-01
This paper presents the numerical investigation performed to calculate the correction factor for Pitot tubes. The purely viscous non-Newtonian fluids with the power-law model constitutive equation were considered. It was shown that the power-law index, the Reynolds number, and the distance between the impact and static tubes have a major influence on the Pitot tube correction factor. The problem was solved for a wide range of these parameters. It was shown that employing Bernoulli's equation could lead to large errors, which depend on the magnitude of the kinetic energy and energy friction loss terms. A neural network model was used to correlate the correction factor of a Pitot tube as a function of these three parameters. This correlation is valid for most Newtonian, pseudoplastic, and dilatant fluids at low Reynolds number.
Microrheological observations of the onset of non-Newtonian behavior in suspensions
Energy Technology Data Exchange (ETDEWEB)
Mondy, L A; Graham, A L; Gottlieb, M
1988-01-01
As the column fraction of solids increases above about 0.30, suspensions of non-Brownian, uniform spheres in Newtonian liquids begin to exhibit shear-thinning, normal stresses, and other non- Newtonian behavior. Here, we report on observations obtained from falling-ball and capillary rheometry at these high volume fractions. Specifically, we find that measured viscosity values are dependent on the size-scale of the viscometer (cylinder diameter, D, and falling- ball diameter, d) relative to the diameter of the suspended spheres d/sub s/. We report the dependence of the measured viscosity on the ratios d/d/sub s/, D/d, and D/d/sub s/, as well as critical values of these ratios above which the apparent viscosity is constant. 5 refs., 3 figs., 1 tab.
Motion of charged suspended particle in a non-Newtonian fluid between two long parallel plates
Energy Technology Data Exchange (ETDEWEB)
Abd Elkhalek, M M [Nuclear Research Center-Atomic Energy Authority, Cairo (Egypt)
1997-12-31
The motion of charged suspended particle in a non-Newtonian fluid between two long parallel plates is discussed. The equation of motion of a suspended particle was suggested by Closkin. The equations of motion are reduced to ordinary differential equations by similarity transformation and solved numerically by using Runge-Kutta method. The trajectories of particles are calculated by integrating the equation of motion of a single particle. The present simulation requires some empirical parameters concerning the collision of the particles with the wall. The effect of solid particles on flow properties are discussed. Some typical results for both fluid and particle phases and density distributions of the particles are presented graphically. 4 figs.
Acoustic waveform of continuous bubbling in a non-Newtonian fluid.
Vidal, Valérie; Ichihara, Mie; Ripepe, Maurizio; Kurita, Kei
2009-12-01
We study experimentally the acoustic signal associated with a continuous bubble bursting at the free surface of a non-Newtonian fluid. Due to the fluid rheological properties, the bubble shape is elongated, and, when bursting at the free surface, acts as a resonator. For a given fluid concentration, at constant flow rate, repetitive bubble bursting occurs at the surface. We report a modulation pattern of the acoustic waveform through time. Moreover, we point out the existence of a precursor acoustic signal, recorded on the microphone array, previous to each bursting. The time delay between this precursor and the bursting signal is well correlated with the bursting signal frequency content. Their joint modulation through time is driven by the fluid rheology, which strongly depends on the presence of small satellite bubbles trapped in the fluid due to the yield stress.
Zhao, Lifei; Li, Zhen; Caswell, Bruce; Ouyang, Jie; Karniadakis, George Em
2018-06-01
We simulate complex fluids by means of an on-the-fly coupling of the bulk rheology to the underlying microstructure dynamics. In particular, a continuum model of polymeric fluids is constructed without a pre-specified constitutive relation, but instead it is actively learned from mesoscopic simulations where the dynamics of polymer chains is explicitly computed. To couple the bulk rheology of polymeric fluids and the microscale dynamics of polymer chains, the continuum approach (based on the finite volume method) provides the transient flow field as inputs for the (mesoscopic) dissipative particle dynamics (DPD), and in turn DPD returns an effective constitutive relation to close the continuum equations. In this multiscale modeling procedure, we employ an active learning strategy based on Gaussian process regression (GPR) to minimize the number of expensive DPD simulations, where adaptively selected DPD simulations are performed only as necessary. Numerical experiments are carried out for flow past a circular cylinder of a non-Newtonian fluid, modeled at the mesoscopic level by bead-spring chains. The results show that only five DPD simulations are required to achieve an effective closure of the continuum equations at Reynolds number Re = 10. Furthermore, when Re is increased to 100, only one additional DPD simulation is required for constructing an extended GPR-informed model closure. Compared to traditional message-passing multiscale approaches, applying an active learning scheme to multiscale modeling of non-Newtonian fluids can significantly increase the computational efficiency. Although the method demonstrated here obtains only a local viscosity from the polymer dynamics, it can be extended to other multiscale models of complex fluids whose macro-rheology is unknown.
Coupled Effects of non-Newtonian Rheology and Aperture Variability on Flow in a Single Fracture
Di Federico, V.; Felisa, G.; Lauriola, I.; Longo, S.
2017-12-01
Modeling of non-Newtonian flow in fractured media is essential in hydraulic fracturing and drilling operations, EOR, environmental remediation, and to understand magma intrusions. An important step in the modeling effort is a detailed understanding of flow in a single fracture, as the fracture aperture is spatially variable. A large bibliography exists on Newtonian and non-Newtonian flow in variable aperture fractures. Ultimately, stochastic or deterministic modeling leads to the flowrate under a given pressure gradient as a function of the parameters describing the aperture variability and the fluid rheology. Typically, analytical or numerical studies are performed adopting a power-law (Oswald-de Waele) model. Yet the power-law model, routinely used e.g. for hydro-fracturing modeling, does not characterize real fluids at low and high shear rates. A more appropriate rheological model is provided by e.g. the four-parameter Carreau constitutive equation, which is in turn approximated by the more tractable truncated power-law model. Moreover, fluids of interest may exhibit yield stress, which requires the Bingham or Herschel-Bulkely model. This study employs different rheological models in the context of flow in variable aperture fractures, with the aim of understanding the coupled effect of rheology and aperture spatial variability with a simplified model. The aperture variation, modeled within a stochastic or deterministic framework, is taken to be one-dimensional and i) perpendicular; ii) parallel to the flow direction; for stochastic modeling, the influence of different distribution functions is examined. Results for the different rheological models are compared with those obtained for the pure power-law. The adoption of the latter model leads to overestimation of the flowrate, more so for large aperture variability. The presence of yield stress also induces significant changes in the resulting flowrate for assigned external pressure gradient.
Modelling the Inflation of Polyisobutylene Into an Elliptic and a Circular Cylinder
DEFF Research Database (Denmark)
Rasmussen, Henrik Koblitz; Gøttsche, Søren; Kjær, Erik Michael
2000-01-01
The isothermal inflation of a sheet of a Polyisobutylene melt into a circular and an elliptic cylinder is modelled using the 3D Lagrangian Integral Method. The non-linear properties of the Polyisobutylene are modelled with the Factorized K-BKZ constitutive equation, using a potential function bas...
Sojka, Paul E.; Rodrigues, Neil S.
2015-11-01
The current study investigates the drop characteristics of three Carboxymethylcellulose (CMC) sprays produced by the impingement of two liquid jets. The three water-based solutions used in this work (0.5 wt.-% CMC-7MF, 0.8 wt.-% CMC-7MF, and 1.4 wt.-% CMC-7MF) exhibited strong shear-thinning, non-Newtonian behavior - characterized by the Bird-Carreau rheological model. A generalized Bird-Carreau jet Reynolds number was used as the primary parameter to characterize the drop size and the drop velocity, which were measured using Phase Doppler Anemometry (PDA). PDA optical configuration enabled a drop size measurement range of approximately 2.3 to 116.2 μm. 50,000 drops were measured at each test condition to ensure statistical significance. The arithmetic mean diameter (D10) , Sauter mean diameter (D32) , and mass median diameter (MMD) were used as representative diameters to characterize drop size. The mean axial drop velocity Uz -mean along with its root-mean square Uz -rms were used to characterize drop velocity. Incredibly, measurements for all three CMC liquids and reference DI water sprays seemed to follow a single curve for D32 and MMD drop diameters in the high generalized Bird-Carreau jet Reynolds number range considered in this work (9.21E +03
Sharifi, Alireza; Niazmand, Hamid
2015-10-01
Carotid siphon is known as one of the risky sites among the human intracranial arteries, which is prone to formation of atherosclerotic lesions. Indeed, scientists believe that accumulation of low density lipoprotein (LDL) inside the lumen is the major cause of atherosclerosis. To this aim, three types of internal carotid artery (ICA) siphon have been constructed to examine variations of hemodynamic parameters in different regions of the arteries. Providing real physiological conditions, blood considered as non-Newtonian fluid and real velocity and pressure waveforms have been employed as flow boundary conditions. Moreover, to have a better estimation of risky sites, the accumulation of LDL particles has been considered, which has been usually ignored in previous relevant studies. Governing equations have been discretized and solved via open source OpenFOAM software. A new solver has been built to meet essential parameters related to the flow and mass transfer phenomena. In contrast to the common belief regarding negligible effect of blood non-Newtonian behavior inside large arteries, current study suggests that the non-Newtonian blood behavior is notable, especially on the velocity field of the U-type model. In addition, it is concluded that neglecting non-Newtonian effects underestimates the LDL accumulation up to 3% in the U-type model at the inner side of both its bends. However, in the V and C type models, non-Newtonian effects become relatively small. Results also emphasize that the outer part of the second bend at the downstream is also at risk similar to the inner part of the carotid bends. Furthermore, from findings it can be implied that the risky sites strongly depend on the ICA shape since the extension of the risky sites are relatively larger for the V-type model, while the LDL concentrations are higher for the C-type model. Copyright © 2015 Elsevier Ltd. All rights reserved.
International Nuclear Information System (INIS)
Hady, F. M.; Ibrahim, F. S.; Abdel-Gaied, S. M.; Eid, M. R.
2011-01-01
The effect of yield stress on the free convective heat transfer of dilute liquid suspensions of nanofluids flowing on a vertical plate saturated in porous medium under laminar conditions is investigated considering the nanofluid obeys the mathematical model of power-law. The model used for non-Newtonian nanofluid incorporates the effects of Brownian motion and thermophoresis. The governing boundary- layer equations are cast into dimensionless system which is solved numerically using a deferred correction technique and Newton iteration. This solution depends on yield stress parameter Ω, a power-law index n, Lewis number Le, a buoyancy-ratio number Nr, a Brownian motion number Nb, and a thermophoresis number Nt. Analyses of the results found that the reduced Nusselt and Sherwood numbers are decreasing functions of the higher yield stress parameter for each dimensionless numbers, n and Le, except the reduced Sherwood number is an increasing function of higher Nb for different values of yield stress parameter
Iqbal, Z.; Mehmood, Zaffar; Ahmad, Bilal
2018-05-01
This paper concerns an application to optimal energy by incorporating thermal equilibrium on MHD-generalised non-Newtonian fluid model with melting heat effect. Highly nonlinear system of partial differential equations is simplified to a nonlinear system using boundary layer approach and similarity transformations. Numerical solutions of velocity and temperature profile are obtained by using shooting method. The contribution of entropy generation is appraised on thermal and fluid velocities. Physical features of relevant parameters have been discussed by plotting graphs and tables. Some noteworthy findings are: Prandtl number, power law index and Weissenberg number contribute in lowering mass boundary layer thickness and entropy effect and enlarging thermal boundary layer thickness. However, an increasing mass boundary layer effect is only due to melting heat parameter. Moreover, thermal boundary layers have same trend for all parameters, i.e., temperature enhances with increase in values of significant parameters. Similarly, Hartman and Weissenberg numbers enhance Bejan number.
Walker, Andrew M; Johnston, Clifton R; Rival, David E
2012-11-01
Although deployed in the vasculature to expand vessel diameter and improve blood flow, protruding stent struts can create complex flow environments associated with flow separation and oscillating shear gradients. Given the association between magnitude and direction of wall shear stress (WSS) and endothelial phenotype expression, accurate representation of stent-induced flow patterns is critical if we are to predict sites susceptible to intimal hyperplasia. Despite the number of stents approved for clinical use, quantification on the alteration of hemodynamic flow parameters associated with the Gianturco Z-stent is limited in the literature. In using experimental and computational models to quantify strut-induced flow, the majority of past work has assumed blood or representative analogs to behave as Newtonian fluids. However, recent studies have challenged the validity of this assumption. We present here the experimental quantification of flow through a Gianturco Z-stent wire in representative Newtonian and non-Newtonian blood analog environments using particle image velocimetry (PIV). Fluid analogs were circulated through a closed flow loop at physiologically appropriate flow rates whereupon PIV snapshots were acquired downstream of the wire housed in an acrylic tube with a diameter characteristic of the carotid artery. Hemodynamic parameters including WSS, oscillatory shear index (OSI), and Reynolds shear stresses (RSS) were measured. Our findings show that the introduction of the stent wire altered downstream hemodynamic parameters through a reduction in WSS and increases in OSI and RSS from nonstented flow. The Newtonian analog solution of glycerol and water underestimated WSS while increasing the spatial coverage of flow reversal and oscillatory shear compared to a non-Newtonian fluid of glycerol, water, and xanthan gum. Peak RSS were increased with the Newtonian fluid, although peak values were similar upon a doubling of flow rate. The introduction of the
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Zeeshan Khan
2018-06-01
Full Text Available In this work, we discuss the unsteady flow of non-Newtonian fluid with the properties of heat source/sink in the presence of thermal radiation moving through a binary mixture embedded in a porous medium. The basic equations of motion including continuity, momentum, energy and concentration are simplified and solved analytically by using Homotopy Analysis Method (HAM. The energy and concentration fields are coupled with Dankohler and Schmidt numbers. By applying suitable transformation, the coupled nonlinear partial differential equations are converted to couple ordinary differential equations. The effect of physical parameters involved in the solutions of velocity, temperature and concentration profiles are discussed by assign numerical values and results obtained shows that the velocity, temperature and concentration profiles are influenced appreciably by the radiation parameter, Prandtl number, suction/injection parameter, reaction order index, solutal Grashof number and the thermal Grashof. It is observed that the non-Newtonian parameter H leads to an increase in the boundary layer thickness. It was established that the Prandtl number decreases thee thermal boundary layer thickness which helps in maintaining system temperature of the fluid flow. It is observed that the temperature profiles higher for heat source parameter and lower for heat sink parameter throughout the boundary layer. Fromm this simulation it is analyzed that an increase in the Schmidt number decreases the concentration boundary layer thickness. Additionally, for the sake of comparison numerical method (ND-Solve and Adomian Decomposition Method are also applied and good agreement is found. Keywords: Unsteady flow, Viscous fluid, Thermal radiation, Porous plate, Arrhenius kinetics, HAM and numerical method
Computational simulation of a non-newtonian model of the blood separation process.
De Gruttola, Sandro; Boomsma, Kevin; Poulikakos, Dimos
2005-12-01
The aim of this work is to construct a computational fluid dynamics model capable of simulating the transient non-Newtonian process of apheresis. A Lagrangian-Eulerian model has been developed which tracks the blood particles within a two-dimensional flow configuration. Within the Eulerian method, the fluid mass and momentum conservation equations within the separator are solved using the density and the viscosity is calculated from the blood particle concentrations. Subsequently, the displacement of the blood particles is calculated with a Lagrangian method. Hawksley's model for the density of supensions is used in the variable density calculation. The viscosity is calculated with two models based on Vand's rigid particle suspension viscosity concepts, followed by the flow field calculation in the separator. Simulations were performed for various inlet hematocrit values and separator lengths. The simulations are in satisfactory agreement with experimental results reported in literature, indicating a complete separation of plasma and red blood cells (RBCs), as well as nearly complete separation of red blood cells and platelets. No hemolysis was observed in the simulations because the shear rate remained under the critical value of 150 N/m2.
Physics of non-Newtonian fluids and interdisciplinary relations (biology and criminology)
Holubova, R.
2018-03-01
The aim of the paper is the presentation of an interdisciplinary topic that allows applying content knowledge in physics, mathematics and biology in real life environment. Students use to play games and view crime scenes but in common they have little knowledge about the science used during crime scene investigation. In this paper the science background of blood spatter analysis is presented—the physics of non-Newtonian fluids, the biology of blood and mathematics—the measurement and calculation of the angle of inpact, the relationship between height and spatter diameter. This topic was choosen according to the analysis of interviews with secondary and high school learners realized at four schools in Moravia, Czech Republic. The topic can be taught at secondary schools so as at a higher level at high schools. Hands-on activities are included. The teaching strategy supports group work. The appropriateness and reasonableness of the topic was checked in the real teaching process and the activities have had a positive feedback.
On a numerical strategy to compute gravity currents of non-Newtonian fluids
International Nuclear Information System (INIS)
Vola, D.; Babik, F.; Latche, J.-C.
2004-01-01
This paper is devoted to the presentation of a numerical scheme for the simulation of gravity currents of non-Newtonian fluids. The two dimensional computational grid is fixed and the free-surface is described as a polygonal interface independent from the grid and advanced in time by a Lagrangian technique. Navier-Stokes equations are semi-discretized in time by the Characteristic-Galerkin method, which finally leads to solve a generalized Stokes problem posed on a physical domain limited by the free surface to only a part of the computational grid. To this purpose, we implement a Galerkin technique with a particular approximation space, defined as the restriction to the fluid domain of functions of a finite element space. The decomposition-coordination method allows to deal without any regularization with a variety of non-linear and possibly non-differentiable constitutive laws. Beside more analytical tests, we revisit with this numerical method some simulations of gravity currents of the literature, up to now investigated within the simplified thin-flow approximation framework
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Luís Felipe Gomes Marinho
Full Text Available Abstract The economics of a mining operation is directly influenced by blasting outcomes, where blasting aims to comminute the rock mass in order to attain smaller grain sizes to be loaded and hauled at a minimum cost for its first processing stage. In order to promote adequate rock breakage, the stemming structure needs to provide proper confinement for the borehole charged with explosives, reflecting the energy released during the detonation in form of shock waves and gases to act throughout the in situ rock mass, enlarging its failures and fractures, and also creating new ones. To build up a stemming column, literature recommends the usage of dry granular materials instead of elements with plastic behavior. However, a study was performed using Gypsum plaster as stemming; a kind of material that exhibits solid-like behavior when it is dry. Following this theory, this test verified improvements regarding confinement effectiveness and energy propagation throughout the rock mass when a non-Newtonian mixture (NNM was applied as stemming; a material that shows a solid-like behavior when is under shear stress. When the stemming arrangement was composed of NNM, it was able to reduce energy and gas losses to the atmosphere, because of the liquid's property of filling voids into the borehole. The NNM yielded high results due to its better confinement effectiveness, a reduction of air overpressure, and an increase of the strain propagation and ground vibration throughout the rock.
Kuchumov, Alex G.; Gilev, Valeriy; Popov, Vitaliy; Samartsev, Vladimir; Gavrilov, Vasiliy
2014-02-01
The paper presents an experimental study of pathological human bile taken from the gallbladder and bile ducts. The flow dependences were obtained for different types of bile from patients with the same pathology, but of different age and sex. The parameters of the Casson's and Carreau's equations were found for bile samples. Results on the hysteretic bile behavior at loading-unloading tests are also presented, which proved that the pathologic bile is a non-Newtonian thixotropic liquid. The viscosity of the gallbladder bile was shown to be higher compared to the duct bile. It was found that at higher shear stress the pathological bile behaves like Newtonian fluid, which is explained by reorientation of structural components. Moreover, some pathological bile flow in the biliary system CFD simulations were performed. The velocity and pressure distributions as well as flow rates in the biliary segments during the gallbladder refilling and emptying phases are obtained. The results of CFD simulations can be used for surgeons to assess the patient's condition and choose an adequate treatment.
Non-Newtonian stress tensor and thermal conductivity tensor in granular plane shear flow
Alam, Meheboob; Saha, Saikat
2014-11-01
The non-Newtonian stress tensor and the heat flux in the plane shear flow of smooth inelastic disks are analysed from the Grad-level moment equations using the anisotropic Gaussian as a reference. Closed-form expressions for shear viscosity, pressure, first normal stress difference (N1) and the dissipation rate are given as functions of (i) the density or the area fraction (ν), (ii) the restitution coefficient (e), (iii) the dimensionless shear rate (R), (iv) the temperature anisotropy [ η, the difference between the principal eigenvalues of the second moment tensor] and (v) the angle (ϕ) between the principal directions of the shear tensor and the second moment tensor. Particle simulation data for a sheared hard-disk system is compared with theoretical results, with good agreement for p, μ and N1 over a large range of density. In contrast, the predictions from a Navier-Stokes order constitutive model are found to deviate significantly from both the simulation and the moment theory even at moderate values of e. We show that the gradient of the deviatoric part of the kinetic stress drives a heat current and the thermal conductivity is characterized by an anisotropic 2nd rank tensor for which explicit expressions are derived.
Non-Newtonian plastic flow of a Ni-Si-B metallic glass at low stresses
International Nuclear Information System (INIS)
Csach, K.; Fursova, Y.V.; Khonik, V.A.; Ocelik, V.
1998-01-01
The problem of the rheological behavior of metallic glasses (MGs) is quite important both from theoretical and practical viewpoints. Early experiments carried out on MGs at temperatures T > 300 K using low shear stress levels revealed plastic flow to be Newtonian while measurements at relative high shear stresses (more than 200 to 400 MPa, depending on temperature, thermal prehistory of samples and chemical composition) indicated a non-linear behavior with 1 < m < 12. Numerous investigations performed later both on as-cast and relaxed MGs of various chemical compositions using a number of testing methods (tensile creep, tensile and bend stress relaxation) showed that a transition from Newtonian behavior at low stresses to a non-linear flow at high stresses was observed. At present, such a situation is considered to be generally accepted. The authors performed precise creep measurements of a Ni-Si-B metallic glass. The results obtained indicate that plastic flow in this case at low tensile stress (12 le σ le 307 MPa) is clearly non-Newtonian and, consequently, the viscosity is stress dependent
Bose, Sayan; Banerjee, Moloy
2015-01-01
Magnetic nanoparticles drug carriers continue to attract considerable interest for drug targeting in the treatment of cancer and other pathological conditions. Magnetic carrier particles with surface-bound drug molecules are injected into the vascular system upstream from the desired target site, and are captured at the target site via a local applied magnetic field. Herein, a numerical investigation of steady magnetic drug targeting (MDT) using functionalized magnetic micro-spheres in partly occluded blood vessel having a 90° bent is presented considering the effects of non-Newtonian characteristics of blood. An Eulerian-Lagrangian technique is adopted to resolve the hemodynamic flow and the motion of the magnetic particles in the flow using ANSYS FLUENT. An implantable infinitely long cylindrical current carrying conductor is used to create the requisite magnetic field. Targeted transport of the magnetic particles in a partly occluded vessel differs distinctly from the same in a regular unblocked vessel. Parametric investigation is conducted and the influence of the insert configuration and its position from the central plane of the artery (zoffset), particle size (dp) and its magnetic property (χ) and the magnitude of current (I) on the "capture efficiency" (CE) is reported. Analysis shows that there exists an optimum regime of operating parameters for which deposition of the drug carrying magnetic particles in a target zone on the partly occluded vessel wall can be maximized. The results provide useful design bases for in vitro set up for the investigation of MDT in stenosed blood vessels.
Non-Newtonian fluids: Frictional pressure loss prediction for fully-developed flow in straight pipes
1991-10-01
ESDU 91025 discusses models used to describe the rheology of time independent pseudohomogeneous non-Newtonian fluids (power-law, Bingham, Herschel-Bulkley and a generalized model due to Metzner and Reed); they are used to calculate the laminar flow pressure drop (which is independent of pipe roughness in this regime). Values of a generalized Reynolds number are suggested to define transitional and turbulent flow. For turbulent flow in smooth pipes, pressure loss is estimated on the basis of an experimentally determined rheogram using either the Dodge-Metzner or Bowen approach depending on the available measurements. Bowen requires results for at least two pipe diameters. The choice of Dodge-Metzner when data are limited is discussed; seven possible methods are assessed against five sets of experimental results drawn from the literature. No method is given for transitional flow, which it is suggested should be avoided, but the turbulent correlation is recommended because it will yield an overestimate. Suggestions are made for the treatment of roughness effects. Several worked examples illustrate the use of the methods and a flowchart guides the user through the process from experimentally characterizing the behavior of the fluid to determining the pressure drop. A computer program, ESDUpac A9125, is also provided.
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Roberto Mei
2018-01-01
Full Text Available The application of a multivariable predictive controller to the mixing process for the production of a non-Newtonian fluid is discussed in this work. A data-driven model has been developed to describe the dynamic behaviour of the rheological properties of the fluid as a function of the operating conditions using experimental data collected in a pilot plant. The developed model provides a realistic process representation and it is used to test and verify the multivariable controller, which has been designed to maintain viscosity curves of the non-Newtonian fluid within a given region of the viscosity-vs-shear rate plane in presence of process disturbances occurring in the mixing process.
International Nuclear Information System (INIS)
Li, Si-Ning; Zhang, Hong-Na; Li, Xiao-Bin; Li, Qian; Li, Feng-Chen; Qian, Shizhi; Joo, Sang Woo
2017-01-01
Highlights: • Heat transfer performance of non-Newtonian fluid flow in a MHS is studied. • Pseudo-plastic fluid flow can clearly promote the heat transfer efficiency in MMC. • Heat transfer enhancement is attributed to the emergence of secondary flow. • The heat transfer uniformity can also be improved by pseudo-plastic fluid flow. - Abstract: As the miniaturization and integration become the leading trend of the micro-electro-mechanical systems, it is of great significance to improve the microscaled heat transfer performance. This paper presents a three-dimensional (3D) numerical simulation on the flow characteristics and heat transfer performance of non-Newtonian fluid flow in a manifold microchannel (MMC) heat sink and traditional microchannel (TMC) heat sink. The non-Newtonian fluid was described by the power-law model. The analyses concentrated on the non-Newtonian fluid effect on the heat transfer performance, including the heat transfer efficiency and uniformity of temperature distribution, as well as the influence of inlet/outlet configurations on fluid flow and heat transfer. Comparing with Newtonian fluid flow, pseudo-plastic fluid could reduce the drag resistance in both MMC and TMC, while the dilatant fluid brought in quite larger drag resistance. For the heat transfer performance, the introduction of pseudo-plastic fluid flow greatly improved the heat transfer efficiency owing to the generation of secondary flow due to the shear-thinning property. Besides, the temperature distribution in MMC was more uniform by using pseudo-plastic fluid. Moreover, the inlet/outlet configuration was also important for the design and arrangement of microchannel heat sinks, since the present work showed that the maximum temperature was prone to locating in the corners near the inlet and outlet. This work provides guidance for optimal design of small-scale heat transfer devices in many cooling applications, such as biomedical chips, electronic systems, and
Physics of Life: A Model for Non-Newtonian Properties of Living Systems
Zak, Michail
2010-01-01
This innovation proposes the reconciliation of the evolution of life with the second law of thermodynamics via the introduction of the First Principle for modeling behavior of living systems. The structure of the model is quantum-inspired: it acquires the topology of the Madelung equation in which the quantum potential is replaced with the information potential. As a result, the model captures the most fundamental property of life: the progressive evolution; i.e. the ability to evolve from disorder to order without any external interference. The mathematical structure of the model can be obtained from the Newtonian equations of motion (representing the motor dynamics) coupled with the corresponding Liouville equation (representing the mental dynamics) via information forces. All these specific non-Newtonian properties equip the model with the levels of complexity that matches the complexity of life, and that makes the model applicable for description of behaviors of ecological, social, and economical systems. Rather than addressing the six aspects of life (organization, metabolism, growth, adaptation, response to stimuli, and reproduction), this work focuses only on biosignature ; i.e. the mechanical invariants of life, and in particular, the geometry and kinematics of behavior of living things. Living things obey the First Principles of Newtonian mechanics. One main objective of this model is to extend the First Principles of classical physics to include phenomenological behavior on living systems; to develop a new mathematical formalism within the framework of classical dynamics that would allow one to capture the specific properties of natural or artificial living systems such as formation of the collective mind based upon abstract images of the selves and non-selves; exploitation of this collective mind for communications and predictions of future expected characteristics of evolution; and for making decisions and implementing the corresponding corrections if
Numerical methods for multi-scale modeling of non-Newtonian flows
Symeonidis, Vasileios
This work presents numerical methods for the simulation of Non-Newtonian fluids in the continuum as well as the mesoscopic level. The former is achieved with Direct Numerical Simulation (DNS) spectral h/p methods, while the latter employs the Dissipative Particle Dynamics (DPD) technique. Physical results are also presented as a motivation for a clear understanding of the underlying numerical approaches. The macroscopic simulations employ two non-Newtonian models, namely the Reiner-Ravlin (RR) and the viscoelastic FENE-P model. (1) A spectral viscosity method defined by two parameters ε, M is used to stabilize the FENE-P conformation tensor c. Convergence studies are presented for different combinations of these parameters. Two boundary conditions for the tensor c are also investigated. (2) Agreement is achieved with other works for Stokes flow of a two-dimensional cylinder in a channel. Comparison of the axial normal stress and drag coefficient on the cylinder is presented. Further, similar results from unsteady two- and three-dimensional turbulent flows past a flat plate in a channel are shown. (3) The RR problem is formulated for nearly incompressible flows, with the introduction of a mathematically equivalent tensor formulation. A spectral viscosity method and polynomial over-integration are studied. Convergence studies, including a three-dimensional channel flow with a parallel slot, investigate numerical problems arising from elemental boundaries and sharp corners. (4) The round hole pressure problem is presented for Newtonian and RR fluids in geometries with different hole sizes. Comparison with experimental data is made for the Newtonian case. The flaw in the experimental assumptions of undisturbed pressure opposite the hole is revealed, while good agreement with the data is shown. The Higashitani-Pritchard kinematical theory for RR, fluids is recovered for round holes and an approximate formula for the RR Stokes hole pressure is presented. The mesoscopic
Diagnosis at a glance of biological non-Newtonian fluids with Film Interference Flow Imaging (FIFI)
Hidema, R.; Yamada, N.; Furukawa, H.
2012-04-01
In the human body, full of biological non-Newtonian fluids exist. For example, synovial fluids exist in our joints, which contain full of biopolymers, such as hyaluronan and mucin. It is thought that these polymers play critical roles on the smooth motion of the joint. Indeed, luck of biopolymers in synovial fluid cause joint pain. Here we study the effects of polymer in thin liquid layer by using an original experimental method called Film Interference Flow Imaging (FIFI). A vertically flowing soap film containing polymers is made as two-dimensional flow to observe turbulence. The thickness of water layer is about 4 μm sandwiched between surfactant mono-layers. The interference pattern of the soap film is linearly related to the flow velocity in the water layer through the change in the thickness of the film. Thus the flow velocity is possibly analyzed by the single image analysis of the interference pattern, that is, FIFI. The grid turbulence was made in the flowing soap films containing the long flexible polymer polyethyleneoxide (PEO, Mw=3.5x106), and rigid polymer hydroxypropyl cellulose (HPC, Mw > 1.0 x106). The decaying process of the turbulence is affected by PEO and HPC at several concentrations. The effects of PEO are sharply seen even at low concentrations, while the effects of HPC are gradually occurred at much higher concentration compared to the PEO. It is assumed that such a difference between PEO and HPC is due to the polymer stretching or polymer orientation under turbulence, which is observed and analyzed by FIFI. We believe the FIFI will be applied in the future to examine biological fluids such as synovial fluids quickly and quantitatively.
Experimental model for non-Newtonian fluid viscosity estimation: Fit to mathematical expressions
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Guillem Masoliver i Marcos
2017-01-01
Full Text Available The construction process of a viscometer, developed in collaboration with a final project student, is here presented. It is intended to be used by first year's students to know the viscosity as a fluid property, for both Newtonian and non-Newtonian flows. Viscosity determination is crucial for the fluids behaviour knowledge related to their reologic and physical properties. These have great implications in engineering aspects such as friction or lubrication. With the present experimental model device three different fluids are analyzed (water, kétchup and a mixture with cornstarch and water. Tangential stress is measured versus velocity in order to characterize all the fluids in different thermal conditions. A mathematical fit process is proposed to be done in order to adjust the results to expected analytical expressions, obtaining good results for these fittings, with R2 greater than 0.88 in any case.
Energy Technology Data Exchange (ETDEWEB)
Yokuda, Satoru T.; Poloski, Adam P.; Adkins, Harold E.; Casella, Andrew M.; Hohimer, Ryan E.; Karri, Naveen K.; Luna, Maria; Minette, Michael J.; Tingey, Joel M.
2009-05-11
The External Flowsheet Review Team (EFRT) has identified the issues relating to the Waste Treatment and Immobilization Plant (WTP) pipe plugging. Per the review’s executive summary, “Piping that transports slurries will plug unless it is properly designed to minimize this risk. This design approach has not been followed consistently, which will lead to frequent shutdowns due to line plugging.” To evaluate the potential for plugging, testing was performed to determine critical velocities for the complex WTP piping layout. Critical velocity is defined as the point at which a moving bed of particles begins to form on the pipe bottom during slurry-transport operations. Pressure drops across the fittings of the test pipeline were measured with differential pressure transducers, from which the critical velocities were determined. A WTP prototype flush system was installed and tested upon the completion of the pressure-drop measurements. We also provide the data for the overflow relief system represented by a WTP complex piping geometry with a non-Newtonian slurry. A waste simulant composed of alumina (nominally 50 μm in diameter) suspended in a kaolin clay slurry was used for this testing. The target composition of the simulant was 10 vol% alumina in a suspending medium with a yield stress of 3 Pa. No publications or reports are available to confirm the critical velocities for the complex geometry evaluated in this testing; therefore, for this assessment, the results were compared to those reported by Poloski et al. (2008) for which testing was performed for a straight horizontal pipe. The results of the flush test are compared to the WTP design guide 24590-WTP-GPG-M-0058, Rev. 0 (Hall 2006) in an effort to confirm flushing-velocity requirements.
International Nuclear Information System (INIS)
Yokuda, Satoru T.; Poloski, Adam P.; Adkins, Harold E.; Casella, Andrew M.; Hohimer, Ryan E.; Karri, Naveen K.; Luna, Maria; Minette, Michael J.; Tingey, Joel M.
2009-01-01
The External Flowsheet Review Team (EFRT) has identified the issues relating to the Waste Treatment and Immobilization Plant (WTP) pipe plugging. Per the review's executive summary, ''Piping that transports slurries will plug unless it is properly designed to minimize this risk. This design approach has not been followed consistently, which will lead to frequent shutdowns due to line plugging.'' To evaluate the potential for plugging, testing was performed to determine critical velocities for the complex WTP piping layout. Critical velocity is defined as the point at which a moving bed of particles begins to form on the pipe bottom during slurry-transport operations. Pressure drops across the fittings of the test pipeline were measured with differential pressure transducers, from which the critical velocities were determined. A WTP prototype flush system was installed and tested upon the completion of the pressure-drop measurements. We also provide the data for the overflow relief system represented by a WTP complex piping geometry with a non-Newtonian slurry. A waste simulant composed of alumina (nominally 50 (micro)m in diameter) suspended in a kaolin clay slurry was used for this testing. The target composition of the simulant was 10 vol% alumina in a suspending medium with a yield stress of 3 Pa. No publications or reports are available to confirm the critical velocities for the complex geometry evaluated in this testing; therefore, for this assessment, the results were compared to those reported by Poloski et al. (2008) for which testing was performed for a straight horizontal pipe. The results of the flush test are compared to the WTP design guide 24590-WTP-GPG-M-0058, Rev. 0 (Hall 2006) in an effort to confirm flushing-velocity requirements.
Simulating non-Newtonian flows with the moving particle semi-implicit method with an SPH kernel
International Nuclear Information System (INIS)
Xiang, Hao; Chen, Bin
2015-01-01
The moving particle semi-implicit (MPS) method and smoothed particle hydrodynamics (SPH) are commonly used mesh-free particle methods for free surface flows. The MPS method has superiority in incompressible flow simulation and simple programing. However, the crude kernel function is not accurate enough for the discretization of the divergence of the shear stress tensor by the particle inconsistency when the MPS method is extended to non-Newtonian flows. This paper presents an improved MPS method with an SPH kernel to simulate non-Newtonian flows. To improve the consistency of the partial derivative, the SPH cubic spline kernel and the Taylor series expansion are combined with the MPS method. This approach is suitable for all non-Newtonian fluids that can be described with τ = μ(|γ|) Δ (where τ is the shear stress tensor, μ is the viscosity, |γ| is the shear rate, and Δ is the strain tensor), e.g., the Casson and Cross fluids. Two examples are simulated including the Newtonian Poiseuille flow and container filling process of the Cross fluid. The results of Poiseuille flow are more accurate than the traditional MPS method, and different filling processes are obtained with good agreement with previous results, which verified the validation of the new algorithm. For the Cross fluid, the jet fracture length can be correlated with We 0.28 Fr 0.78 (We is the Weber number, Fr is the Froude number). (paper)
Molecular dosimetry based on radiation induced degradation of polyisobutylene
International Nuclear Information System (INIS)
Joerkov Thomsen, Kristina
1999-01-01
This project investigates the possibility of qualitative measurement of radiation doses through detection of changes in the average molecular weight in the polymer Polyisobutylene (PIB). Changes in molecular weight and molecular weight distribution is detected by Gel Permeation Chromatography (GPC). The aim of the project is to decide whether or not it is possible to determine a quality difference between α-radiation ( 241 Am, 5,5 MeV) and γ-radiation ( 60 Co, 1,25 MeV) in the dose range 0,5 to 10 kGy by irradiation of PIB. Irradiation with 60 Co changes the average number molecular weight M n by 12% per kGy and the average weight molecular weight M w by 23% per kGy. The presence of antioxidant in the irradiated sample inhibits a change in average molecular weight by 5% and 16% for M n and M w respectively. (au)
A Wall Boundary Condition for the Simulation of a Turbulent Non-Newtonian Domestic Slurry in Pipes
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Dhruv Mehta
2018-01-01
Full Text Available The concentration (using a lesser amount of water of domestic slurry promotes resource recovery (nutrients and biomass while saving water. This article is aimed at developing numerical methods to support engineering processes such as the design and implementation of sewerage for concentrated domestic slurry. The current industrial standard for computational fluid dynamics-based analyses of turbulent flows is Reynolds-averaged Navier–Stokes (RANS modelling. This is assisted by the wall function approach proposed by Launder and Spalding, which permits the use of under-refined grids near wall boundaries while simulating a wall-bounded flow. Most RANS models combined with wall functions have been successfully validated for turbulent flows of Newtonian fluids. However, our experiments suggest that concentrated domestic slurry shows a Herschel–Bulkley-type non-Newtonian behaviour. Attempts have been made to derive wall functions and turbulence closures for non-Newtonian fluids; however, the resulting laws or equations are either inconsistent across experiments or lack relevant experimental support. Pertinent to this study, laws or equations reported in literature are restricted to a class of non-Newtonian fluids called power law fluids, which, as compared to Herschel–Bulkley fluids, yield at any amount of applied stress. An equivalent law for Herschel–Bulkley fluids that require a minimum-yield stress to flow is yet to be reported in literature. This article presents a theoretically derived (with necessary approximations law of the wall for Herschel–Bulkley fluids and implements it in a RANS solver using a specified shear approach. This results in a more accurate prediction of the wall shear stress experienced by a circular pipe with a turbulent Herschel–Bulkley fluid flowing through it. The numerical results are compared against data from our experiments and those reported in literature for a range of Reynolds numbers and rheological
DEFF Research Database (Denmark)
Jabbaribehnam, Mirmasoud; Spangenberg, Jon; Hattel, Jesper Henri
2016-01-01
In this paper, the migration of secondary particles in a non-Newtonian ceramic slurry inthe tape casting process is investigated with the purpose of understanding the particle distribution patterns along the casting direction. The Ostwald-de Waele power law model for the non-Newtonian flow...... the substratevelocity (casting speed) leads to a more uniform distribution of the particles inside the ceramic slurry, in which case the shear induced particle migration is dominating over the gravity induced one....
Numerical Modeling of Mixing of Chemically Reacting, Non-Newtonian Slurry for Tank Waste Retrieval
International Nuclear Information System (INIS)
Yuen, D.A.; Onishi, Y.
2001-01-01
In the U.S. Department of Energy (DOE) complex, 100 million gallons of radioactive and chemical wastes from plutonium production are stored in 281 underground storage tanks. Retrieval of the wastes from the tanks is the first step in its ultimate treatment and disposal. Because billions of dollars are being spent on this effort, waste retrieval demands a strong scientific basis for its successful completion. As will be discussed in Section 4.2, complex interactions among waste chemical reactions, rheology, and mixing of solid and liquid tank waste (and possibly with a solvent) will occur in DSTs during the waste retrieval (mixer pump) operations. The ultimate goal of this study was to develop the ability to simulate the complex chemical and rheological changes that occur in the waste during processing for retrieval. This capability would serve as a scientific assessment tool allowing a priori evaluation of the consequences of proposed waste retrieval operations. Hanford tan k waste is a multiphase, multicomponent, high-ionic strength, and highly basic mixture of liquids and solids. Wastes stored in the 4,000-m3 DSTs will be mixed by 300-hp mixer pumps that inject high-speed (18.3 m/s) jets to stir up the sludge and supernatant liquid for retrieval. During waste retrieval operations, complex interactions occur among waste mixing, chemical reactions, and associated rheology. Thus, to determine safe and cost-effective operational parameters for waste retrieval, decisions must rely on new scientific knowledge to account for physical mixing of multiphase flows, chemical reactions, and waste rheology. To satisfy this need, we integrated a computational fluid dynamics code with state-of-the-art equilibrium and kinetic chemical models and non-Newtonian rheology (Onishi (and others) 1999). This development is unique and holds great promise for addressing the complex phenomena of tank waste retrieval. The current model is, however, applicable only to idealized tank waste
Frolov, S V; Sindeev, S V; Liepsch, D; Balasso, A
2016-05-18
According to the clinical data, flow conditions play a major role in the genesis of intracranial aneurysms. The disorder of the flow structure is the cause of damage of the inner layer of the vessel wall, which leads to the development of cerebral aneurysms. Knowledge of the alteration of the flow field in the aneurysm region is important for treatment. The aim is to study quantitatively the flow structure in an patient-specific aneurysm model of the internal carotid artery using both experimental and computational fluid dynamics (CFD) methods with Newtonian and non-Newtonian fluids. A patient-specific geometry of aneurysm of the internal carotid artery was used. Patient data was segmented and smoothed to obtain geometrical model. An elastic true-to-scale silicone model was created with stereolithography. For initial investigation of the blood flow, the flow was visualized by adding particles into the silicone model. The precise flow velocity measurements were done using 1D Laser Doppler Anemometer with a spatial resolution of 50 μ m and a temporal resolution of 1 ms. The local velocity measurements were done at a distance of 4 mm to each other. A fluid with non-Newtonian properties was used in the experiment. The CFD simulations for unsteady-state problem were done using constructed hexahedral mesh for Newtonian and non-Newtonian fluids. Using 1D laser Doppler Anemometer the minimum velocity magnitude at the end of systole -0.01 m/s was obtained in the aneurysm dome while the maximum velocity 1 m/s was at the center of the outlet segment. On central cross section of the aneurysm the maximum velocity value is only 20% of the average inlet velocity. The average velocity on the cross-section is only 11% of the inlet axial velocity. Using the CFD simulation the wall shear stresses for Newtonian and non-Newtonian fluid at the end of systolic phase (t= 0.25 s) were computed. The wall shear stress varies from 3.52 mPa (minimum value) to 10.21 Pa (maximum value) for the
Electro-osmosis of non-Newtonian fluids in porous media using lattice Poisson-Boltzmann method.
Chen, Simeng; He, Xinting; Bertola, Volfango; Wang, Moran
2014-12-15
Electro-osmosis in porous media has many important applications in various areas such as oil and gas exploitation and biomedical detection. Very often, fluids relevant to these applications are non-Newtonian because of the shear-rate dependent viscosity. The purpose of this study was to investigate the behaviors and physical mechanism of electro-osmosis of non-Newtonian fluids in porous media. Model porous microstructures (granular, fibrous, and network) were created by a random generation-growth method. The nonlinear governing equations of electro-kinetic transport for a power-law fluid were solved by the lattice Poisson-Boltzmann method (LPBM). The model results indicate that: (i) the electro-osmosis of non-Newtonian fluids exhibits distinct nonlinear behaviors compared to that of Newtonian fluids; (ii) when the bulk ion concentration or zeta potential is high enough, shear-thinning fluids exhibit higher electro-osmotic permeability, while shear-thickening fluids lead to the higher electro-osmotic permeability for very low bulk ion concentration or zeta potential; (iii) the effect of the porous medium structure depends significantly on the constitutive parameters: for fluids with large constitutive coefficients strongly dependent on the power-law index, the network structure shows the highest electro-osmotic permeability while the granular structure exhibits the lowest permeability on the entire range of power law indices considered; when the dependence of the constitutive coefficient on the power law index is weaker, different behaviors can be observed especially in case of strong shear thinning. Copyright © 2014 Elsevier Inc. All rights reserved.
Directory of Open Access Journals (Sweden)
Xiankang Xin
2017-10-01
Full Text Available In this paper, physical experiments and numerical simulations were applied to systematically investigate the non-Newtonian flow characteristics of heavy oil in porous media. Rheological experiments were carried out to determine the rheology of heavy oil. Threshold pressure gradient (TPG measurement experiments performed by a new micro-flow method and flow experiments were conducted to study the effect of viscosity, permeability and mobility on the flow characteristics of heavy oil. An in-house developed novel simulator considering the non-Newtonian flow was designed based on the experimental investigations. The results from the physical experiments indicated that heavy oil was a Bingham fluid with non-Newtonian flow characteristics, and its viscosity-temperature relationship conformed to the Arrhenius equation. Its viscosity decreased with an increase in temperature and a decrease in asphaltene content. The TPG measurement experiments was impacted by the flow rate, and its critical flow rate was 0.003 mL/min. The TPG decreased as the viscosity decreased or the permeability increased and had a power-law relationship with mobility. In addition, the critical viscosity had a range of 42–54 mPa∙s, above which the TPG existed for a given permeability. The validation of the designed simulator was positive and acceptable when compared to the simulation results run in ECLIPSE V2013.1 and Computer Modelling Group (CMG V2012 software as well as when compared to the results obtained during physical experiments. The difference between 0.0005 and 0.0750 MPa/m in the TPG showed a decrease of 11.55% in the oil recovery based on the simulation results, which demonstrated the largely adverse impact the TPG had on heavy oil production.
The influence of pH on gas-liquid mass transfer in non-Newtonian fluids
Li Shaobai; Fan Jungeng; Xu Shuang; Li Rundong; Luan Jingde
2017-01-01
In this study, the effect of pH on the mass transfer of oxygen bubble swarms in non-Newtonian fluids was experimentally studied. The volumetric liquid side mass transfer coefficient (kLa), liquid side mass transfer coefficient (kL), and specific interfacial area (a) were investigated. The pH was regulated by the addition of hydrochloric acid and sodium hydroxide (NaOH). It was found that the kLa increased with the gas flow rate increasing and decreased with the apparent viscosity of the liqui...
Vasanth, K. R.; Hanumagowda, B. N.; Santhosh Kumar, J.
2018-04-01
Squeeze film investigations focus upon film pressure, load bearing quantity and the minimum thickness of film. The combined effect of pressure viscous dependent and non- Newtonian couple stress in porous annular plate is studied. The modified equations of one dimensional pressure, load bearing quantity, non dimensional squeeze time are obtained. The conclusions obtained in the study are found to be in very good agreement compared to the previous results which are published. The load carrying capacity is increased due to the variation in the pressure dependent viscosity and also due to the couple stress effect. Finally this results in change in the squeeze film timings.
Linking the fractional derivative and the Lomnitz creep law to non-Newtonian time-varying viscosity
Pandey, Vikash; Holm, Sverre
2016-01-01
Many of the most interesting complex media are non-Newtonian and exhibit time-dependent behavior of thixotropy and rheopecty. They may also have temporal responses described by power laws. The material behavior is represented by the relaxation modulus and the creep compliance. On the one hand, it is shown that in the special case of a Maxwell model characterized by a linearly time-varying viscosity, the medium's relaxation modulus is a power law which is similar to that of a fractional deriva...
Almazmumy, Mariam; Ebaid, Abdelhalim
2017-08-01
In this article, the flow and heat transfer of a non-Newtonian nanofluid between two coaxial cylinders through a porous medium has been investigated. The velocity, temperature, and nanoparticles concentration of the present mathematical model are governed by a system of nonlinear ordinary differential equations. The objective of this article is to obtain new exact solutions for the temperature and the nanoparticles concentration and, therefore, compare them with the previous approximate results in the literature. Moreover, the velocity equation has been numerically solved. The effects of the pressure gradient, thermophoresis, third-grade, Brownian motion, and porosity parameters on the included phenomena have been discussed through several tables and plots. It is found that the velocity profile is increased by increasing the pressure gradient parameter, thermophoresis parameter (slightly), third-grade parameter, and Brownian motion parameter (slightly); however, it decreases with an increase in the porosity parameter and viscosity power index. In addition, the temperature and the nanoparticles concentration reduce with the strengthen of the Brownian motion parameter, while they increase by increasing the thermophoresis parameter. Furthermore, the numerical solution and the physical interpretation in the literature for the same problem have been validated with the current exact analysis, where many remarkable differences and errors have been concluded. Therefore, the suggested analysis may be recommended with high trust for similar problems.
Deposition Velocities of Newtonian and Non-Newtonian Slurries in Pipelines
Energy Technology Data Exchange (ETDEWEB)
Poloski, Adam P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Adkins, Harold E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Abrefah, John [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Casella, Andrew M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hohimer, Ryan E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Nigl, Franz [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Minette, Michael J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Toth, James J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Tingey, Joel M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Yokuda, Satoru T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
2009-03-01
correlation used in the WTP design guide has been shown to be inaccurate for Hanford waste feed materials. The use of the Thomas (1979) correlation in the design guide is not conservative—In cases where 100% of the particles are smaller than 74 μm or particles are considered to be homogeneous due to yield stress forces suspending the particles the homogeneous fraction of the slurry can be set to 100%. In such cases, the predicted critical velocity based on the conservative Oroskar and Turian (1980) correlation is reduced to zero and the design guide returns a value from the Thomas (1979) correlation. The measured data in this report show that the Thomas (1979) correlation predictions often fall below that measured experimental values. A non-Newtonian deposition velocity design guide should be developed for the WTP— Since the WTP design guide is limited to Newtonian fluids and the WTP expects to process large quantities of such materials, the existing design guide should be modified address such systems. A central experimental finding of this testing is that the flow velocity required to reach turbulent flow increases with slurry rheological properties due to viscous forces dampening the formation of turbulent eddies. The flow becomes dominated by viscous forces rather than turbulent eddies. Since the turbulent eddies necessary for particle transport are not present, the particles will settle when crossing this boundary called the transitional deposition boundary. This deposition mechanism should be expected and designed for in the WTP.
Point-of-care Devices: Non-Newtonian Whole Blood Behavior and Capillary Flow on Reagent-coated Walls
Directory of Open Access Journals (Sweden)
Jean BERTHIER
2016-08-01
Full Text Available Most point-of-care (POC and patient self-testing (PST devices are based on the analysis of whole blood taken from a finger prick. Whole blood contains a bountiful of information about the donor’s health. We analyze here two particularities of microsystems for blood analysis: the blood non-Newtonian behavior, and the capillary flow in reagent-coated channels. Capillarity is the most commonly used method to move fluids in portable systems. It is shown first that the capillary flow of blood does not follow the Lucas-Washburn-Rideal law when the capillary flow velocity is small, due to its non-Newtonian rheology and to the formation of rouleaux of RBCs. In a second step, the capillary flow of blood on reagent-coated surfaces is investigated; first experimentally by observing the spreading of a droplet of blood on different reagent-coated substrates; second theoretically and numerically using the general law for spontaneous capillary flows and the Evolver numerical program.
Iwamatsu, Masao
2017-07-01
The spreading of a cap-shaped spherical droplet of non-Newtonian power-law liquids, both shear-thickening and shear-thinning liquids, that completely wet a spherical substrate is theoretically investigated in the capillary-controlled spreading regime. The crater-shaped droplet model with the wedge-shaped meniscus near the three-phase contact line is used to calculate the viscous dissipation near the contact line. Then the energy balance approach is adopted to derive the equation that governs the evolution of the contact line. The time evolution of the dynamic contact angle θ of a droplet obeys a power law θ∼t^{-α} with the spreading exponent α, which is different from Tanner's law for Newtonian liquids and those for non-Newtonian liquids on a flat substrate. Furthermore, the line-tension dominated spreading, which could be realized on a spherical substrate for late-stage of spreading when the contact angle becomes low and the curvature of the contact line becomes large, is also investigated.
Tembely, Moussa; Alsumaiti, Ali M.; Jouini, Mohamed S.; Rahimov, Khurshed; Dolatabadi, Ali
2017-11-01
Most of the digital rock physics (DRP) simulations focus on Newtonian fluids and overlook the detailed description of rock-fluid interaction. A better understanding of multiphase non-Newtonian fluid flow at pore-scale is crucial for optimizing enhanced oil recovery (EOR). The Darcy scale properties of reservoir rocks such as the capillary pressure curves and the relative permeability are controlled by the pore-scale behavior of the multiphase flow. In the present work, a volume of fluid (VOF) method coupled with an adaptive meshing technique is used to perform the pore-scale simulation on a 3D X-ray micro-tomography (CT) images of rock samples. The numerical model is based on the resolution of the Navier-Stokes equations along with a phase fraction equation incorporating the dynamics contact model. The simulations of a single phase flow for the absolute permeability showed a good agreement with the literature benchmark. Subsequently, the code is used to simulate a two-phase flow consisting of a polymer solution, displaying a shear-thinning power law viscosity. The simulations enable to access the impact of the consistency factor (K), the behavior index (n), along with the two contact angles (advancing and receding) on the relative permeability.
DEFF Research Database (Denmark)
Truelsen, Jens Høg; Kops, Jørgen; Pedersen, Walther Batsberg
2000-01-01
A macroinitiator was prepared from a triblock copolymer of polyisobutylene (PIB) with end blocks of poly(p-methylstyrene) (P(p-MeS)) by bromination to obtain initiating bromomethyl groups for atom transfer radical polymerization (ATRP). Controlled polymerization of styrene and p-acetoxystyrene yi......A macroinitiator was prepared from a triblock copolymer of polyisobutylene (PIB) with end blocks of poly(p-methylstyrene) (P(p-MeS)) by bromination to obtain initiating bromomethyl groups for atom transfer radical polymerization (ATRP). Controlled polymerization of styrene and p...
The influence of pH on gas-liquid mass transfer in non-Newtonian fluids
Directory of Open Access Journals (Sweden)
Li Shaobai
2017-01-01
Full Text Available In this study, the effect of pH on the mass transfer of oxygen bubble swarms in non-Newtonian fluids was experimentally studied. The volumetric liquid side mass transfer coefficient (kLa, liquid side mass transfer coefficient (kL, and specific interfacial area (a were investigated. The pH was regulated by the addition of hydrochloric acid and sodium hydroxide (NaOH. It was found that the kLa increased with the gas flow rate increasing and decreased with the apparent viscosity of the liquid increasing. In the case of pH 7 was attributed to the decomposition of the Xanthan molecular structure by the hydroxyl of NaOH.
Energy Technology Data Exchange (ETDEWEB)
Mey, Paula; Varges, Priscilla R.; Mendes, Paulo R. de Souza [Dept. of Mechanical Engineering. Pontificia Universidade Catolica do RJ (PUC-Rio), RJ (Brazil)], e-mails: prvarges@puc-rio.br, pmendes@puc-rio.br
2010-07-01
This research looked for a method to determine the binary diffusion coefficient D of salts in liquids (especially in drilling fluids) not only accurately, but in a reasonable time. We chose to use the Taylor Dispersion Method. This technique has been used for measuring binary diffusion coefficients in gaseous, liquid and supercritical fluids, due to its simplicity and accuracy. In the method, the diffusion coefficient is determined by the analysis of the dispersion of a pulse of soluble material in a solvent flowing laminarly through a tube. This work describes the theoretical basis and the experimental requirements for the application of the Taylor Dispersion Method, emphasizing the description of our experiment. A mathematical formulation for both Newtonian and non-Newtonian fluids is presented. The relevant sources of errors are discussed. The experimental procedure and associated analysis are validated by applying the method in well known systems, such as NaCl in water.D of salts in liquids (especially in drilling fluids) not only accurately, but in a reasonable time. We chose to use the Taylor Dispersion Method. This technique has been used for measuring binary diffusion coefficients in gaseous, liquid and supercritical fluids, due to its simplicity and accuracy. In the method, the diffusion coefficient is determined by the analysis of the dispersion of a pulse of soluble material in a solvent flowing laminarly through a tube. This work describes the theoretical basis and the experimental requirements for the application of the Taylor Dispersion Method, emphasizing the description of our experiment. A mathematical formulation for both Newtonian and non-Newtonian fluids is presented. The relevant sources of errors are discussed. The experimental procedure and associated analysis are validated by applying the method in well known systems, such as NaCl in water. (author)
Energy Technology Data Exchange (ETDEWEB)
Friedel, T. [Schlumberger Data and Consulting Services, Sugar Land, TX (United States)
2006-07-01
There are many damage mechanisms associated with hydraulically fractured gas wells. These include hydraulic damage caused by invading fluids during the treatment and damage due to the stresses exerted on the fracture face. Damage to the proppant pack can also reduce conductivity and non-Darcy flow. However, these are not the only impacts of impaired productivity in tight-gas reservoirs, which do not respond to hydraulic fracturing as expected. Some sustain a flat production profile or show only a slow increase in production rate for several weeks or months. This is due to poor rock quality, strong stress dependency in permeability, hydraulic and mechanical damage. Another reason for the poor performance is related to the cleanup of the cross-linked fracturing fluid with its non-Newtonian characteristics. This paper presented an improved 3-phase cleanup model for the investigation of polymer gel cleanup. Yield stress was considered according to the Herschel-Bulkley rheology model. The viscosity model is based on the exact analytical solution, including the plug flow zone. According to data in the published literature, half of the gel phase can be recovered. The gel saturation gradually increases towards the fracture tips, thereby lowering the fracture conductivities. The residing gel damages the permeability and porosity of the proppant pack or causes damage to the fracture face, thereby reducing production potential. These results are in agreement with field observations where fracture half-lengths, conductivities and productivity are also lower than expected. Preliminary results suggest that capillary forces and load-water recovery have little influence on gel cleanup. 16 refs., 2 tabs., 17 figs.
Directory of Open Access Journals (Sweden)
K. Mehala
2016-12-01
Full Text Available The hydrodynamic bearings are stressed by severe workings conditions, such as speed, load, and the oil will be increasingly solicit by pressure and shear. The Newtonian behavior is far from being awarded in this case, the most loaded bearings operating at very high speeds; the shear rate of the oil is of higher order. A numerical analysis of the behavior of non-Newtonian fluid for plain cylindrical journal bearing finite dimension coated with antifriction material with a high tin content, for to facilitate the accommodation of the surfaces and save the silk of the shaft in the case of a contact. this analyses is implemented using the code-ANSYS CFX, by solving the energy equation with the finite difference method, considering that laminar regime and the fluid is non Newtonian by using the power law Ostwald model, the coefficient n is equal to 1.25 and for different model such as Bingham, cross and Hereshek-Bulkley model. This study aims to better predict the non-Newtonian behavior of the oil film in bearings operating under more severe conditions. The purpose conducted during this study is to predict the effect of non-Newtonian behavior of the film; the journal bearing operating under severe conditions, the speed of rotation varies from 1000 to 9000 rpm and the bearing working under radial load 2 to 10 kN. Temperature and the pressure within the fluid film assumed non-Newtonian are high, with a coefficient n greater than 1 that is to say for viscoelastic fluids.
International Nuclear Information System (INIS)
Marques, Rosana G.G.; Tavares, Maria I.B.
2001-01-01
The evaluation of spin-lattice relaxation times of 1 H for polyisobutylene/paraffin systems, were obtained using the classic inversion recovery technique, and also through Cross Polarization Magic Angle Spinning (CP/MAS) techniques varying the contact time and also by the delayed contact time pulse sequence. NMR results showed that the polyisobutylene/paraffin systems in which high molecular weight paraffins were used, is heterogeneous. However, for paraffins with low molecular weight, the system presents good homogeneity. (author)
Young, Paul M; Traini, Daniela; Ong, Hui Xin; Granieri, Angelo; Zhu, Bing; Scalia, Santo; Song, Jie; Spicer, Patrick T
2017-10-01
Thickening polymers have been used as excipients in nasal formulations to avoid nasal run-off (nasal drip) post-administration. However, increasing the viscosity of the formulation can have a negative impact on the quality of the aerosols generated. Therefore, the study aims to investigate the use of a novel smart nano-cellulose excipient to generate suitable droplets for nasal drug delivery that simultaneously has only marginally increased viscosity while still reducing nasal drips. Nasal sprays containing nano-cellulose at different concentrations were investigated for the additive's potential as an excipient. The formulations were characterized for their rheological and aerosol properties. This was then compared to conventional nasal spray formulation containing the single-component hydroxyl-propyl methyl cellulose (HPMC) viscosity enhancing excipient. The HPMC-containing nasal formulations behave in a Newtonian manner while the nano-cellulose formulations have a yield stress and shear-thinning properties. At higher excipient concentrations and shear rates, the nano-cellulose solutions have significantly lower viscosities compared to the HPMC solution, resulting in improved droplet formation when actuated through conventional nasal spray. Nano-cellulose materials could potentially be used as a suitable excipient for nasal drug delivery, producing consistent aerosol droplet size, and enhanced residence time within the nasal cavity with reduced run-offs compared to conventional polymer thickeners.
Motion of a suspended charged particle in a NON-Newtonian fluid. Vol. 2
Energy Technology Data Exchange (ETDEWEB)
Abdel-Khalek, M M [Nuclear Research Center, Atomic Energy Authority, Cairo (Egypt)
1996-03-01
The path lines of a solid spherical charged particle suspended in a non-newton electrical conducting viscous fluid through two infinite parallel plates in the presence of a constant magnetic field normal to the plane of particle motion were determined. The effect of some parameters such as particle volume, fluid density, fluid viscosity, and the use magnetic field strength on these path lines were determined. The present solution requires some empirical parameters concerning the collision of the particles with the wall. The differential equations of motion were numerically solved by Runge-Kutta method. Some conclusions about width, maximum height and number of collisions with upper and lower plates were deduced. 4 figs.
Directory of Open Access Journals (Sweden)
M. H. Yazdi
2014-01-01
Full Text Available In the present study, the first and second law analyses of power-law non-Newtonian flow over embedded open parallel microchannels within micropatterned permeable continuous moving surface are examined at prescribed surface temperature. A similarity transformation is used to reduce the governing equations to a set of nonlinear ordinary differential equations. The dimensionless entropy generation number is formulated by an integral of the local rate of entropy generation along the width of the surface based on an equal number of microchannels and no-slip gaps interspersed between those microchannels. The velocity, the temperature, the velocity gradient, and the temperature gradient adjacent to the wall are substituted into this equation resulting from the momentum and energy equations obtained numerically by Dormand-Prince pair and shooting method. Finally, the entropy generation numbers, as well as the Bejan number, are evaluated. It is noted that the presence of the shear thinning (pseudoplastic fluids creates entropy along the surface, with an opposite effect resulting from shear thickening (dilatant fluids.
Eglit, M. E.; Yakubenko, A. E.; Yakubenko, T. A.
2017-10-01
This paper deals with the mathematical and numerical modeling of the propagation stage of geophysical gravity-driven flows, such as snow avalanches, mudflows, and rapid landslides. New mathematical models are presented which are based on full, not-depth-averaged equations of mechanics of continuous media. The models account for three important issues: non-Newtonian rheology of the moving material, entrainment of the bed material by the flow, and turbulence. The main objective is to investigate the effect of these three factors on the flow dynamics and on the value of the entrainment rate. To exclude the influence of many other factors, e.g., the complicated slope topography, only the motion down a long uniform slope with a constant inclination angle is studied numerically. Moreover, the entire flow from the front to the rear area was not modeled, but only its middle part where the flow is approximately uniform in length. One of the qualitative results is that in motion along homogeneous slope the mass entrainment increases the flow velocity and depth while the entrainment rate at large time tends to become constant which depends on the physical properties of the flow and the underlying material but not on the current values of the flow velocity and depth.
The LS-STAG immersed boundary/cut-cell method for non-Newtonian flows in 3D extruded geometries
Nikfarjam, F.; Cheny, Y.; Botella, O.
2018-05-01
The LS-STAG method is an immersed boundary/cut-cell method for viscous incompressible flows based on the staggered MAC arrangement for Cartesian grids, where the irregular boundary is sharply represented by its level-set function, results in a significant gain in computer resources (wall time, memory usage) compared to commercial body-fitted CFD codes. The 2D version of LS-STAG method is now well-established (Cheny and Botella, 2010), and this paper presents its extension to 3D geometries with translational symmetry in the z direction (hereinafter called 3D extruded configurations). This intermediate step towards the fully 3D implementation can be applied to a wide variety of canonical flows and will be regarded as the keystone for the full 3D solver, since both discretization and implementation issues on distributed memory machines are tackled at this stage of development. The LS-STAG method is then applied to various Newtonian and non-Newtonian flows in 3D extruded geometries (axisymmetric pipe, circular cylinder, duct with an abrupt expansion) for which benchmark results and experimental data are available. The purpose of these investigations are (a) to investigate the formal order of accuracy of the LS-STAG method, (b) to assess the versatility of method for flow applications at various regimes (Newtonian and shear-thinning fluids, steady and unsteady laminar to turbulent flows) (c) to compare its performance with well-established numerical methods (body-fitted and immersed boundary methods).
Entropy analysis of convective MHD flow of third grade non-Newtonian fluid over a stretching sheet
Directory of Open Access Journals (Sweden)
M.M. Rashidi
2017-03-01
Full Text Available The purpose of this article is to study and analyze the convective flow of a third grade non-Newtonian fluid due to a linearly stretching sheet subject to a magnetic field. The dimensionless entropy generation equation is obtained by solving the reduced momentum and energy equations. The momentum and energy equations are reduced to a system of ordinary differential equations by a similarity method. The optimal homotopy analysis method (OHAM is used to solve the resulting system of ordinary differential equations. The effects of the magnetic field, Biot number and Prandtl number on the velocity component and temperature are studied. The results show that the thermal boundary-layer thickness gets decreased with increasing the Prandtl number. In addition, Brownian motion plays an important role to improve thermal conductivity of the fluid. The main purpose of the paper is to study the effects of Reynolds number, dimensionless temperature difference, Brinkman number, Hartmann number and other physical parameters on the entropy generation. These results are analyzed and discussed.
Linking the fractional derivative and the Lomnitz creep law to non-Newtonian time-varying viscosity
Pandey, Vikash; Holm, Sverre
2016-09-01
Many of the most interesting complex media are non-Newtonian and exhibit time-dependent behavior of thixotropy and rheopecty. They may also have temporal responses described by power laws. The material behavior is represented by the relaxation modulus and the creep compliance. On the one hand, it is shown that in the special case of a Maxwell model characterized by a linearly time-varying viscosity, the medium's relaxation modulus is a power law which is similar to that of a fractional derivative element often called a springpot. On the other hand, the creep compliance of the time-varying Maxwell model is identified as Lomnitz's logarithmic creep law, making this possibly its first direct derivation. In this way both fractional derivatives and Lomnitz's creep law are linked to time-varying viscosity. A mechanism which yields fractional viscoelasticity and logarithmic creep behavior has therefore been found. Further, as a result of this linking, the curve-fitting parameters involved in the fractional viscoelastic modeling, and the Lomnitz law gain physical interpretation.
RF magnetron sputtering and evaporation of polyisobutylene and low density polyethylene
Czech Academy of Sciences Publication Activity Database
Kousal, J.; Hanuš, J.; Choukourov, A.; Hlídek, P.; Biederman, H.; Slavinská, D.; Zemek, Josef
2005-01-01
Roč. 200, 1-4 (2005), s. 472-475 ISSN 0257-8972 R&D Projects: GA MŠk(CZ) OC 527.10; GA MŠk(CZ) ME 553 Institutional research plan: CEZ:AV0Z10100521 Keywords : magnetron * radio frequency * sputtering * polyethylene * polyisobutylene Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.646, year: 2005
DEFF Research Database (Denmark)
Ratkovich, Nicolas Rios; Majumder, S.K.; Bentzen, Thomas Ruby
2013-01-01
Gas-Newtonian liquid two-phase flows (TPFs) are presented in several industrial processes (e.g. oil-gas industry). In spite of the common occurrence of these TPFs, the understanding of them is limited compared to single-phase flows. Various studies on TPF focus on developing empirical correlations...... based on large sets of experimental data for void fraction, which have proven accurate for specific conditions for which they were developed limiting their applicability. On the other hand, few studies focus on gas-non-Newtonian liquids TPFs, which are very common in chemical processes. The main reason...... is due to the characterization of the viscosity, which determines the hydraulic regime and flow behaviours of the system. The focus of this study is the analysis of the TPF (slug flow) for Newtonian and non-Newtonian liquids in a vertical pipe in terms of void fraction using computational fluid dynamics...
El-Amin, Mohamed
2011-05-14
In this paper, a finite difference scheme is developed to solve the unsteady problem of combined heat and mass transfer from an isothermal curved surface to a porous medium saturated by a non-Newtonian fluid. The curved surface is kept at constant temperature and the power-law model is used to model the non-Newtonian fluid. The explicit finite difference method is used to solve simultaneously the equations of momentum, energy and concentration. The consistency of the explicit scheme is examined and the stability conditions are determined for each equation. Boundary layer and Boussinesq approximations have been incorporated. Numerical calculations are carried out for the various parameters entering into the problem. Velocity, temperature and concentration profiles are shown graphically. It is found that as time approaches infinity, the values of wall shear, heat transfer coefficient and concentration gradient at the wall, which are entered in tables, approach the steady state values.
Shi, Lei; Young, Trevor L; Kim, Jincheol; Sheng, Yun; Wang, Lei; Chen, Yifeng; Feng, Zhiqiang; Keevers, Mark J; Hao, Xiaojing; Verlinden, Pierre J; Green, Martin A; Ho-Baillie, Anita W Y
2017-08-02
Metal halide perovskite solar cells (PSCs) have undergone rapid progress. However, unstable performance caused by sensitivity to environmental moisture and high temperature is a major impediment to commercialization of PSCs. In the present work, a low-temperature, glass-glass encapsulation technique using high performance polyisobutylene (PIB) as the moisture barrier is investigated on planar glass/FTO/TiO 2 /FAPbI 3 /PTAA/gold perovskite solar cells. PIB was applied as either an edge seal or blanket layer. Electrical connections to the encapsulated PSCs were provided by either the FTO or Au layers. Results of a "calcium test" demonstrated that a PIB edge-seal effectively prevents moisture ingress. A shelf life test was performed and the PIB-sealed PSC was stable for at least 200 days. Damp heat and thermal cycling tests, in compliance with IEC61215:2016, were used to evaluate different encapsulation methods. Current-voltage measurements were performed regularly under simulated AM1.5G sunlight to monitor changes in PCE. The best results we have achieved to date maintained the initial efficiency after 540 h of damp heat testing and 200 thermal cycles. To the best of the authors' knowledge, these are among the best damp heat and thermal cycle test results for perovskite solar cells published to date. Given the modest performance of the cells (8% averaged from forward and reverse scans) especially with the more challenging FAPbI 3 perovskite material tested in this work, it is envisaged that better stability results can be further achieved when higher performance perovskite solar cells are encapsulated using the PIB packaging techniques developed in this work. We propose that heat rather than moisture was the main cause of our PSC degradation. Furthermore, we propose that preventing the escape of volatile decomposition products from the perovskite solar cell materials is the key for stability. PIB encapsulation is a very promising packaging solution for perovskite
Thandlam, Anil Kumar; Das, Chiranjib; Majumder, Subrata Kumar
2017-04-01
Investigation of wall-liquid mass transfer and heat transfer phenomena with gas-Newtonian and non-Newtonian fluids in vertically helical coil reactor have been reported in this article. Experiments were conducted to investigate the effect of various dynamic and geometric parameters on mass and heat transfer coefficients in the helical coil reactor. The flow pattern-based heat and mass transfer phenomena in the helical coil reactor are highlighted at different operating conditions. The study covered a wide range of geometric parameters such as diameter of the tube ( d t ), diameter of the coil ( D c ), diameter of the particle ( d p ), pitch difference ( p/D c ) and concentrations of non-Newtonian liquid. The correlation models for the heat and mass transfer coefficient based on the flow pattern are developed which may be useful in process scale-up of the helical coil reactor for industrial application. The frictional drag coefficient was also estimated and analyzed by mass transfer phenomena based on the electrochemical method.
Hassan Fathabadi
2013-01-01
In this study, several novel numerical solutions are presented to solve the turbulent filtration equation and its special case called “Non-Newtonian mechanical filtration equation”. The turbulent filtration equation in porous media is a very important equation which has many applications to solve the problems appearing especially in mechatronics, micro mechanic and fluid mechanic. Many applied mechanical problems can be solved using this equation. For example, non-Newtonian mechanical filtrat...
International Nuclear Information System (INIS)
Heine, Jennifer; Rodehorst, Uta; Badillo, Juan Pablo; Winter, Martin; Bieker, Peter
2015-01-01
ABSTRACT: The side reactions of LiO 2 , Li 2 O 2 and Li 2 O, formed during the discharge process at the cathode/electrolyte interphase, are still a main challenge of lithium-air batteries. During these reactions, polyvinylidene difluoride (PVdF), as the commonly used cathode binder material, is decomposing, leading to a shorter lifetime of the battery. In this paper, we introduced and investigated polyisobutylene (PIB), a chemically and electrochemically inert polymeric material, to substitute PVdF as binder for lithium-air batteries. Results obtained by X-ray diffraction and spectroscopic methods showed, that PIB is far more stable in the presence of O 2 − , O 2 2− as well as O 2− species compared to PVdF. This distinct inertness makes PIB a promising binder for lithium-air batteries
Zhang, Hefeng
2015-12-17
A series of hydroxyl-terminated polyisobutylene-b-polyethylene (PIB-b-PE-OH) copolymers were synthesized by combining living cationic polymerization and polyhomologation. Allyl-terminated PIBs, synthesized by living cationic polymerization, were hydroborated with BH3·THF to produce 3-arm boron-linked stars, PIB3B, which served as macroinitiators for the in situ polyhomologation of dimethylsulfoxonium methylide. The resulting 3-arm star block copolymers, (PIB-b-PE)3B, were oxidized/hydrolysed to afford PIB-b-PE-OH. Characterization of all intermediates and final products by high temperature gel permeation chromatography (HT-GPC) and proton nuclear magnetic resonance spectroscopy (1H NMR) revealed the well-defined character of the copolymers. The thermal properties of the copolymers were studied by differential scanning calorimetry (DSC).
Rahmani, L.; Seghier, O.; Benmoussa, A.; Draoui, B.
2018-06-01
The most of operations of chemical, biochemical or petrochemical industries are carried out in tanks or in reactors which are mechanically-controlled. The optimum mode of operation of these devices requires a finalized knowledge of the thermo-hydrodynamic behavior induced by the agitator. In the present work, the characterization of the incompressible hydrodynamic and thermal fields of a non-Newtonian fluid (Bingham) in a flat, non-baffled cylindrical vessel fitted with anchor agitator was undertaken by numerical simulation, using the CFD code Fluent (6.3.26) based on the finite volume discretization method of the energy equation and the Navier-Stokes equations which are formulated in (U.V.P) variables. We have summarized this simulated system by comparing of the consumed power and the Nusselt number for this type of mobile (Anchor agitator).
Ignatenko, Yaroslav; Bocharov, Oleg; May, Roland
2017-10-01
Solids transport is a major issue in high angle wells. Bed-load forms by sediment while transport and accompanied by intermittent contact with stream-bed by rolling, sliding and bouncing. The study presents the results of a numerical simulation of a laminar steady-state flow around a particle at rest and in free motion in a shear flow of Herschel-Bulkley fluid. The simulation was performed using the OpenFOAM open-source CFD package. A criterion for particle incipient motion and entrainment into suspension from cuttings bed (Shields criteria) based on forces and torques balance is discussed. Deflection of the fluid parameters from the ones of Newtonian fluid leads to decreasing of the drag and lift forces and the hydrodynamic moment. Thus, the critical shear stress (Shields parameter) for the considered non-Newtonian fluid must be greater than the one for a Newtonian fluid.
Directory of Open Access Journals (Sweden)
Hemeidia A. M.
2006-11-01
Full Text Available Rheological properties of Saudi Arab-Light, Arab-Berri and Arab-Heavy crude oils were measured with Brookfield Viscometer (LVT Model at temperatures 10, 15, 20, 25, 38, 55 and 70°C. Saudi Arab-Light and Arab-Heavy exhibit non-Newtonian behavior at temperature less than or equal to 20°C, while Saudi Arab-Berri behaves as a non-Newtonian fluid at all temperatures. The main reason for this rheological behavior can be attributed to the thermal and shear histories; the relative amounts of wax and asphaltene content in Saudi crude oils as well. Therefore, Statistical Analysis (t-test was used to check the variability of the change in rheological behavior of Saudi non-Newtonian crude oils at a confidence level of 95%. The evaluation ensured that, all non-Newtonian data were statistically not different and were correlated with power-law model. Under turbulent flow conditions the pipeline design calculations were carried out through a computer program. Les propriétés rhéologiques des bruts séoudiens Arab-Light, Arab-Berri et Arab-Heavy ont été mesurées à l'aide d'un viscomètre Brookfield (modèle LVT à des températures de 10, 15, 20, 25, 38, 55 et 70°C. Les Saudi Arab-Light et Arab-Heavy présentent un comportement non newtonien à des températures égales ou inférieures à 20°C, tandis que le Saudi Arab-Berri se comporte comme un fluide non newtonien à toutes les températures. Ce comportement rhéologique est principalement dû aux historiques thermiques et de cisaillement, de même qu'aux quantités relatives de paraffine et à la teneur en asphaltène des bruts séoudiens. Une analyse statistique (essai t a donc été menée pour vérifier la variabilité des changements de comportement rhéologique des bruts séoudiens non newtoniens à un degré de fiabilité de 95%. Il en est ressorti que toutes les données non newtoniennes étaient statistiquement non différentes et étaient en corrélation avec le modèle de la loi des
Directory of Open Access Journals (Sweden)
Moussa Tembely
2017-10-01
Full Text Available Most of the pore-scale imaging and simulations of non-Newtonian fluid are based on the simplifying geometry of network modeling and overlook the fluid rheology and heat transfer. In the present paper, we developed a non-isothermal and non-Newtonian numerical model of the flow properties at pore-scale by simulation of the 3D micro-CT images using a Finite Volume Method (FVM. The numerical model is based on the resolution of the momentum and energy conservation equations. Owing to an adaptive mesh generation technique and appropriate boundary conditions, rock permeability and mobility are accurately computed. A temperature and concentration-dependent power-law viscosity model in line with the experimental measurement of the fluid rheology is adopted. The model is first applied at isothermal condition to 2 benchmark samples, namely Fontainebleau sandstone and Grosmont carbonate, and is found to be in good agreement with the Lattice Boltzmann method (LBM. Finally, at non-isothermal conditions, an effective mobility is introduced that enables to perform a numerical sensitivity study to fluid rheology, heat transfer, and operating conditions. While the mobility seems to evolve linearly with polymer concentration in agreement with a derived theoretical model, the effect of the temperature seems negligible by comparison. However, a sharp contrast is found between carbonate and sandstone under the effect of a constant temperature gradient. Besides concerning the flow index and consistency factor, a master curve is derived when normalizing the mobility for both the carbonate and the sandstone.
Broniarz-Press, L; Sosnowski, T R; Matuszak, M; Ochowiak, M; Jabłczyńska, K
2015-05-15
The paper contains results of the experimental study on atomization process of aqueous solutions of glycerol and aqueous solutions of glycerol-polyacrylamide (Rokrysol WF1) in an ultrasonic inhaler. In experiments the different concentration aqueous solutions of glycerol and glycerol-polyacrylamide have been tested. The results have been obtained by the use of laser diffraction technique. The differences between characteristics of ultrasonic atomization for test liquids have been observed. The analysis of drop size histograms shows that the different sizes of drops have been formed during atomization process. The present study confirmed the previous reports which suggested that the drops size changes with the increase in viscosity of solution changes in spray characteristics were also observed. It has been shown that the shear and extensional viscosities affect the process of atomization. Copyright © 2015 Elsevier B.V. All rights reserved.
The flow of a non-Newtonian fluid induced due to the oscillations of a porous plate
Directory of Open Access Journals (Sweden)
S. Asghar
2004-01-01
Full Text Available An analytic solution of the flow of a third-grade fluid on a porous plate is constructed. The porous plate is executing oscillations in its own plane with superimposed injection or suction. An increasing or decreasing velocity amplitude of the oscillating porous plate is also examined. It is also shown that in case of third-grade fluid, a combination of suction/injection and decreasing/increasing velocity amplitude is possible as well. Several limiting situations with their implications are given and discussed.
Energy Technology Data Exchange (ETDEWEB)
Escudier, M.P.; Smith, S. [Department of Engineering, Mechanical Engineering, University of Liverpool, Brownlow Hill, Liverpool L69 3GH (United Kingdom); Oliveira, P.J. [Departamento de Engenharia Electromecanica, Universidade da Beira Interior, Rua Marques D' Avila e Boloma, 6200 Covilha (Portugal); Pinho, F.T. [Centro de Estudos de Fenomenos de Transporte, DEMEGI, Faculdade de Engenharia, Universidade do Porto, Rua Roberto Frias, 4200-465 Porto (Portugal)
2002-07-01
Experimental data are reported for fully developed laminar flow of a shear-thinning liquid through both a concentric and an 80% eccentric annulus with and without centrebody rotation. The working fluid was an aqueous solution of 0.1% xanthan gum and 0.1% carboxymethylcellulose for which the flow curve is well represented by the Cross model. Comparisons are reported between numerical calculations and the flow data, as well as with other laminar annular-flow data for a variety of shear-thinning liquids previously reported in the literature. In general, the calculations are in good quantitative agreement with the experimental data, even in situations where viscoelastic effects, neglected in the calculations, would be expected to play a role. (orig.)
DEFF Research Database (Denmark)
Ratkovich, Nicolas Rios; Bentzen, Thomas Ruby; Majumder, S.K.
2012-01-01
Gas-Newtonian liquid two-phase flows (TPFs) are presented in several industrial processes (i.e. oil-gas industry). In spite of the common occurrence of these TPFs, their understanding is limited compared to single-phase flows. Different studies on TPF have focus on developing empirical correlations...... based in large sets of experiment data for void fraction and pressure drop which have proven to be accurate for specific condition that their where developed for, which limit their applicability. On the other hand, scarce studies focus on gas-non-Newtonian liquids TPFs, which are very common in chemical...... processes. The main reason for it is due to the characterization of the viscosity, which determines the hydraulic regime and flow behaviours on the system. The focus of this study is the analysis of the TPF for Newtonian and non-Newtonian liquids in a vertical pipe in terms of void fraction and total...
Applicability of mode-coupling theory to polyisobutylene: a molecular dynamics simulation study.
Khairy, Y; Alvarez, F; Arbe, A; Colmenero, J
2013-10-01
The applicability of Mode Coupling Theory (MCT) to the glass-forming polymer polyisobutylene (PIB) has been explored by using fully atomistic molecular dynamics simulations. MCT predictions for the so-called asymptotic regime have been successfully tested on the dynamic structure factor and the self-correlation function of PIB main-chain carbons calculated from the simulated cell. The factorization theorem and the time-temperature superposition principle are satisfied. A consistent fitting procedure of the simulation data to the MCT asymptotic power-laws predicted for the α-relaxation regime has delivered the dynamic exponents of the theory-in particular, the exponent parameter λ-the critical non-ergodicity parameters, and the critical temperature T(c). The obtained values of λ and T(c) agree, within the uncertainties involved in both studies, with those deduced from depolarized light scattering experiments [A. Kisliuk et al., J. Polym. Sci. Part B: Polym. Phys. 38, 2785 (2000)]. Both, λ and T(c)/T(g) values found for PIB are unusually large with respect to those commonly obtained in low molecular weight systems. Moreover, the high T(c)/T(g) value is compatible with a certain correlation of this parameter with the fragility in Angell's classification. Conversely, the value of λ is close to that reported for real polymers, simulated "realistic" polymers and simple polymer models with intramolecular barriers. In the framework of the MCT, such finding should be the signature of two different mechanisms for the glass-transition in real polymers: intermolecular packing and intramolecular barriers combined with chain connectivity.
Campbell, Christopher Garrett
Polyisobutylene is a polymer of high commercial and academic interest due to its low cost of synthesis, high gas barrier properties, and high chemical and oxidative stability. Polyisobutylene (PIB) can only be synthesized by the cationic polymerization of isobutylene (IB). Commercial processes are currently only capable of producing monofunctional PIB or copolymers thereof. The living cationic polymerization of isobutylene is capable of producing difunctional telechelic PIB, but at the expense of difficultly or expensively synthesized initiators. Thus there exists a need for new synthetic routes for multifunctional PIBs, which can be adopted on a commercial scale. In the first project, we demonstrated a new reaction, which is a subset of the Friedel Crafts alkylation reaction, in which the alkylating carbocation undergoes a cleavage reaction prior to reaction with the aromatic substrate. This reaction was discovered by the observation that when a PIB containing a large amount of coupled fraction was subjected to a mixture of protic and Lewis acids (HCl/TiCl4) in the presence of an alkoxybenzene compound, the coupled fraction was quantitatively converted to its constituent monofunctional chains, which became functionalized by the alkoxybenzene. In the second project, a commercial polymer, poly(isobutylene- co-isoprene) (butyl rubber) was used as a substrate upon which the aforementioned electrophilic cleavage and functionalization reaction was performed. The goal of this project was to degrade a high molecular weight, main-chain olefin-containing copolymer of isobutylene into low molecular weight difunctional telechelic polyisobutylenes. This general process, though not necessarily proceeding by the aforementioned novel chemical reaction, has been described in the literature as "constructive degradation." Though we were unable to synthesize truly telechelic polyisobutylenes by this method, we were able to demonstrate this method as a viable route to low molecular
Strip waves in vibrated shear-thickening wormlike micellar solutions
Epstein, T.; Deegan, R. D.
2010-06-01
We present an instability in vertically vibrated dilute wormlike micellar solutions. Above a critical driving acceleration the fluid forms elongated solitary domains of high amplitude waves. We model this instability using a Mathieu equation modified to account for the non-Newtonian character of the fluid. We find that our model successfully reproduces the observed transitions.
Energy Technology Data Exchange (ETDEWEB)
Marques, Rosana G.G. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas - CENPES]. E-mail: garrido@cenpes.petrobras.com.br; Tavares, Maria I.B. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Inst. de Macromoleculas]. E-mail: mibt@ima.ufrj.br
2001-07-01
The evaluation of spin-lattice relaxation times of {sup 1}H for polyisobutylene/paraffin systems, were obtained using the classic inversion recovery technique, and also through Cross Polarization Magic Angle Spinning (CP/MAS) techniques varying the contact time and also by the delayed contact time pulse sequence. NMR results showed that the polyisobutylene/paraffin systems in which high molecular weight paraffins were used, is heterogeneous. However, for paraffins with low molecular weight, the system presents good homogeneity. (author)
Institute of Scientific and Technical Information of China (English)
Huai-chao Wang; Ming-zu Zhang; Pei-hong Ni; Jin-lin He; Ying Hao; Yi-xian Wu
2013-01-01
Two pH-responsive amphiphilic diblock copolymers,namely polyisobutylene-block-poly[2-(N,N-dimethylamino)ethyl methacrylate] (PIB-b-PDMAEMA) and polyisobutylene-block-poly(metharylic acid) (PIB-b-PMAA),were synthesized via oxyanion-initiated polymerization,and their multiple self-assembly behaviors have been studied.An exo-o1efin-terminated highly reactive polyisobutylene (HRPIB) was first changed to hydroxyl-terminated PIB (PIB-OH) via hydroboration-oxidation of C=C double bond in the chain end,and then reacted with KH to yield a potassium alcoholate of PIB (PIB-O-K+).PIB-O-K+ was immediately used as a macroinitiator to polymerize DMAEMA monomer,resulting in a cationic diblock copolymer PIB-b-PDMAEMA.With the similar synthesis procedure,the anionic diblock copolymer PIB-b-PMAA could be prepared via a combination of oxyanion-initiated polymerization of tert-butyl methacrylate (tBMA) and subsequent hydrolysis of tert-butyl ester groups in PtBMA block.The functional PIB and block copolymers have been fully characterized by 1H-NMR,FT-IR spectroscopy,and gel permeation chromatography (GPC).These samples allowed us to systematically investigate the effects of block composition on the pH responsivity and various self-assembled morphologies of the copolymers in THF/water mixed solvent.Transmission electron microscopy (TEM) images revealed that these diblock copolymers containing small amount of original PIB without exo-olefin-terminated group are able to self-assemble into micelles,vesicles with different particle sizes and cylindrical aggregates,depending on various factors including block copolymer composition,solvent polarity and pH value.
Kumar, Rajeev Ananda; Zheng, Bin; Huang, Kuo-Wei; Emert, Jack I.; Faust, Rudolf
2014-01-01
The polymerization of isobutylene (IB) to yield highly reactive polyisobutylene (HR PIB) with high exo-olefin content using GaCl3 or FeCl3·diisopropyl ether complexes has been previously reported.1 In an effort to further improve polymerization rates and exo-olefin content, we have studied ethylaluminum dichloride (EADC) complexes with diisopropyl ether, 2-chloroethyl ethyl ether (CEEE), and bis(2-chloroethyl) ether (CEE) as catalysts in conjunction with tert-butyl chloride as initiator in hexanes at different temperatures. All three complexes were readily soluble in hexanes. Polymerization, however, was only observed with CEE. At 0 °C polymerization was complete in 5 min at [t-BuCl] = [EADC·CEE] = 10 mM and resulted in PIB with ∼70% exo-olefin content. Studies on complexation using ATR FTIR and 1H NMR spectroscopy revealed that at 1:1 stoichiometry a small amount of EADC remains uncomplexed. By employing an excess of CEE, exo-olefin contents increased up to 90%, while polymerization rates decreased only slightly. With decreasing temperature, polymerization rates decreased while molecular weights as well as exo-olefin contents increased, suggesting that isomerization has a higher activation energy than β-proton abstraction. Density functional theory (DFT) studies on the Lewis acid·ether binding energies indicated a trend consistent with the polymerization results. The polymerization mechanism proposed previously for Lewis acid·ether complexes1 adequately explains all the findings. © 2014 American Chemical Society.
Kumar, Rajeev Ananda
2014-03-25
The polymerization of isobutylene (IB) to yield highly reactive polyisobutylene (HR PIB) with high exo-olefin content using GaCl3 or FeCl3·diisopropyl ether complexes has been previously reported.1 In an effort to further improve polymerization rates and exo-olefin content, we have studied ethylaluminum dichloride (EADC) complexes with diisopropyl ether, 2-chloroethyl ethyl ether (CEEE), and bis(2-chloroethyl) ether (CEE) as catalysts in conjunction with tert-butyl chloride as initiator in hexanes at different temperatures. All three complexes were readily soluble in hexanes. Polymerization, however, was only observed with CEE. At 0 °C polymerization was complete in 5 min at [t-BuCl] = [EADC·CEE] = 10 mM and resulted in PIB with ∼70% exo-olefin content. Studies on complexation using ATR FTIR and 1H NMR spectroscopy revealed that at 1:1 stoichiometry a small amount of EADC remains uncomplexed. By employing an excess of CEE, exo-olefin contents increased up to 90%, while polymerization rates decreased only slightly. With decreasing temperature, polymerization rates decreased while molecular weights as well as exo-olefin contents increased, suggesting that isomerization has a higher activation energy than β-proton abstraction. Density functional theory (DFT) studies on the Lewis acid·ether binding energies indicated a trend consistent with the polymerization results. The polymerization mechanism proposed previously for Lewis acid·ether complexes1 adequately explains all the findings. © 2014 American Chemical Society.
DEFF Research Database (Denmark)
Jabbari, Masoud; Bulatova, Regina; Hattel, Jesper Henri
2014-01-01
The aim of the present study is to evaluate the different interface capturing methods as well as to find the best approach for flow modeling of the ceramic slurry in the tape casting process. The conventional volume of fluid (VOF) method with three different interpolation methods for interface...... method for the free surface capturing during the flow of a ceramic slurry described by a constitutive power law equation in the tape casting process. First the developed model is tested against well-documented and relevant solutions from literature involving free surface tracking and subsequently...
Directory of Open Access Journals (Sweden)
Keivan Shayesteh
2015-02-01
Full Text Available In tubular reactors, there are different parameters which can affect the degree of conversion. The type of fluid motion and velocity profile of substances in the reactor are of most central measures. Different rheological models can be employed to study the behavior of fluids; power law model is one of the most commonly used models. In this study, the rheological behaviour of polymerization reaction of methyl methacrylate was examined. Due to the similarity function of tubular and batch reactors, the number of test tubes are used to prepare the solution. After preparation of the reactor solution, the n value of power law model was estimated within the span of 0.3492 to 0.9889 by curve fitting. Employing these rheological data, a reactor has been designed. Moreover, the effects of parameters such as reaction temperature, initiator wt%, the concentration of monomer and reactor’s radius on the degree of conversion have been studied. The obtained results in the research indicate a direct proportionality of conversion with the reaction temperature, initiator wt% and the concentration of monomer and also an inverse proportionality of conversion with reactor’s radius. Finally, the amount of conversion was obtained equal to 56.47% and according to its laboratory proportion which was 55.88% we have reached the conclusion that the modeling duly undertaken is applicable and valid.
Abou-zeid, Mohamed Y.; Mohamed, Mona A. A.
2017-09-01
This article is an analytic discussion for the motion of power-law nanofluid with heat transfer under the effect of viscous dissipation, radiation, and internal heat generation. The governing equations are discussed under the assumptions of long wavelength and low Reynolds number. The solutions for temperature and nanoparticle profiles are obtained by using homotopy perturbation method. Results for the behaviours of the axial velocity, temperature, and nanoparticles as well as the skin friction coefficient, reduced Nusselt number, and Sherwood number with other physical parameters are obtained graphically and analytically. It is found that as the power-law exponent increases, both the axial velocity and temperature increase, whereas nanoparticles decreases. These results may have applicable importance in the research discussions of nanofluid flow in channels with small diameters under the effect of different temperature distributions.
Vacuum polarization and non-Newtonian gravitation
International Nuclear Information System (INIS)
Long, D.R.
1980-01-01
Gell-Mann and Low have emphasized that, as first pointed out by Uehling and Serber, vacuum polarization effects produce a logarithmic modification to the Coulomb potential at small distances. Here, it is pointed out that, if these same considerations are applied to gravitation, the logarithmic term will have a sign opposite to that in the Coulomb case and in agreement with recent laboratory results on the gravitational ''constant''. Of considerable importance is the fact that such vacuum polarization effects cannot be observed in null experiments to test the gravitational inverse square law because the polarizing field is absent. It is a striking circumstance that the coefficient of the logarithm in QED is nearly the same as that found in gravitational experiments. (author)
Energy Technology Data Exchange (ETDEWEB)
Kauder, K.; Deipenwisch, R. [Dortmund Univ. (Germany). FG Fluidenergiemaschinen
1998-12-31
The model of the calculation of the friction losses caused by oil described in this report delivers a starting point for the integration of the design parameter `oil` for oil injected screw-type engines. The use of non newtonian oils with a shear thinning behaviour lead to a decrease of energy consumption over a broad speed range of screw-type compressors. The decrease is mainly caused by the shear indicated lower viscosity in the clearances of the compressor. A difficulty through the use of this oils is the estimation of the conditions in the clearances. The rate of shear in the single clearance is influenced by the relative speed of the boundaries and by the height of the clearance during operation. Up to now only cold heights were used in the model. To improve the quality of the model the clearances of a running screw compressor were measured. The losses which were determined at the screw compressor test plant are the summation of all losses including the losses caused by the power transmission and in the bearings. Experiments at a model rotor test stand make the determination of the friction losses and the losses by the acceleration of the oil in the clearances possible. A better calculation model shall deliver the conditions to describe the influence of the oil on the energy efficiency and to define the optimal oil for every screw compressor. (orig.) [Deutsch] Das beschriebene Modell zur Berechnung der hydraulischen Verluste in der nasslaufenden Schraubenmaschine liefert Ansaetze, um das Oel schon bei der Auslegung der Schraubenkompressoren als Konstruktionselement mit einzubeziehen. Sinnvoll ist die Nutzung eines nicht-newtonschen Oeles immer dann, wenn eine deutliche scherindizierte Viskositaetserniedrigung in dem Schergeschwindigkeitsbereich, der in den Spalten des Schraubenkompressors vorliegt, erreicht werden kann. Beim Einsatz dieser Oele besteht die Schwierigkeit darin, den Schergeschwindigkeitsbereich vorherzubestimmen, der waehrend des Betriebs in dem
Droplet breakup driven by shear thinning solutions in a microfluidic T-junction
Chiarello, Enrico; Gupta, Anupam; Mistura, Giampaolo; Sbragaglia, Mauro; Pierno, Matteo
2017-12-01
Droplet-based microfluidics turned out to be an efficient and adjustable platform for digital analysis, encapsulation of cells, drug formulation, and polymerase chain reaction. Typically, for most biomedical applications, the handling of complex, non-Newtonian fluids is involved, e.g., synovial and salivary fluids, collagen, and gel scaffolds. In this study, we investigate the problem of droplet formation occurring in a microfluidic T-shaped junction, when the continuous phase is made of shear thinning liquids. At first, we review in detail the breakup process, providing extensive, side-by-side comparisons between Newtonian and non-Newtonian liquids over unexplored ranges of flow conditions and viscous responses. The non-Newtonian liquid carrying the droplets is made of Xanthan solutions, a stiff, rodlike polysaccharide displaying a marked shear thinning rheology. By defining an effective Capillary number, a simple yet effective methodology is used to account for the shear-dependent viscous response occurring at the breakup. The droplet size can be predicted over a wide range of flow conditions simply by knowing the rheology of the bulk continuous phase. Experimental results are complemented with numerical simulations of purely shear thinning fluids using lattice Boltzmann models. The good agreement between the experimental and numerical data confirm the validity of the proposed rescaling with the effective Capillary number.
Gass-Assisted Displacement of Non-Newtonian Fluids
DEFF Research Database (Denmark)
Rasmussen, Henrik Koblitz; Eriksson, Torbjörn Gerhard
2003-01-01
in a circular cylinder. This is a simple model system used to investigate the gas-fluid displacement, as the problem is reduced to an axis-symmetric flow problem. The understanding of this process is relevant for the geometrically much more complex polymer processing operation Gas-assisted injection moulding...... (GAIM). This is a process, where a mould is filled partly with a polymer melt followed by the injection of inert gas into the core of the polymer melt. The numerical analysis of the fluid flow concerning the experimental observations data in these publications is all based on Newtonian or general...... equation of Boger fluids is the Oldroyd-B model. This model has, with success, been able to describe the complex flow behaviours of Boger fluid. Though, refinements in the flow analysis can be obtained using more complex constitutive models. To keep the flow analysis as simple as possible the Oldroyd...
Saffman-Taylor Instability for a non-Newtonian fluid
Daripa, Prabir
2013-11-01
Motivated by applications, we study classical Saffman-Taylor instability involving displacement of an Oldroyd-B fluid displaced by air in a Hele-Shaw cell. The lubrication approximation is used by neglecting the vertical component of the velocity. We obtain an explicit expression of one of the components of the extra-stress perturbations tensor in terms of the horizontal velocity perturbations. The main result is an explicit formula for the growth constant (in time) of perturbations, given by a ratio in which a term depending on the relaxation and retardation (time) constants appears in the denominator of the ratio. This exact result compares extremely well with known numerical results. It is found that flow is more unstable than the corresponding Newtonian case. This is a joint work with Gelu Pasa. The research has been made possible by an NPRP Grant # 08-777-1-141 from the Qatar National Research Fund (a member of the Qatar Foundation).
Controllability of Non-Newtonian Fluids Under Homogeneous Flows
National Research Council Canada - National Science Library
Wilson, Lynda M
2007-01-01
.... The constitutive models are as follows: the Phan-Thien-Tanner model; the Johnson-Segalman model; and the Doi model. The effect of extensional flow on these models and the effect of shear flow on the Doi model have not been explored previous to this work...
Fundamentals of convection in non-Newtonian fluids
International Nuclear Information System (INIS)
Chen, J.L.S.; Ekmann, J.M.; Peterson, G.P.
1987-01-01
There are five papers in this book. They are: Pressure Drop and Heat Transfer in Viscoelastic Duct Flow - A New Look, A Heat Transfer Correlation for Viscoelastic Pipe Flows under Constant Wall Heat Flux, Three-Dimensional Solidification and Flow of Polymers in Curved Square Ducts, Natural Convecon Heat Transfer Between a Power-Law Fluid and a Permeable Isothermal Vertical Wall, and On Nonisothermal Flows of Bingham Plastics
The turbulent mixing of non-Newtonian fluids
Demianov, A. Yu; Doludenko, A. N.; Inogamov, N. A.; Son, E. E.
2013-07-01
The turbulence caused by the Rayleigh-Taylor instability represents a complicated phenomenon. It is usually related to the major hydrodynamic activities, the tangling of the media contact boundary, merging, separation and intermixing of originally smoothed initial structures. An important role in the theory of the Rayleigh-Taylor instability is played by the discontinuity of density on a contact interface between two homogeneous (in terms of density) fluids. A numerical modeling of the intermixing of two fluids with different rheology whose densities differ twice as a result of the Rayleigh-Taylor instability has been carried out. The coefficients of turbulent intermixing in a multimode statement of the problem for the Bingham, dilatant and pseudo-plastic fluids have been obtained.
Aerosol entrainment from a sparged non-Newtonian slurry
International Nuclear Information System (INIS)
Fritz, Brad G.
2006-01-01
Aerosol measurements were conducted above a half-scale air sparged mixing tank filled with simulated waste slurry. Three aerosol size fractions were measured at three sampling heights at three different sparging rates using a filter based ambient air sampling technique. Aerosol concentrations in the head space above the closed tank demonstrated a wide range, varying between 97 ?g m-3 for PM2.5 and 5650 ?g m-3 for TSP. The variation in concentrations was a function of sampling heights, size fraction and sparging rate. Measured aerosol entrainment coefficients showed good agreement with existing entrainment models. The models evaluated generally over predicted the entrainment, but were within a factor of two of the measured entrainment. This indicates that the range of applicability of the models may be extendable to include sparged slurries with Bingham plastic rheological properties
Non Newtonian Behavior of Blood in Presence of Arterial Occlusion
Dr.Arun Kumar Maiti
2016-01-01
The objective of the present numerical model is to investigate the effect of shape of stenosis on blood flow through an artery using Bingham plastic fluid model. Blood is modeled as Bingham plastic fluid in a uniform circular tube with an axially symmetric but radially non symmetric stenosis. The expressions for flux, dimensionless resistance to flow with stenosis shape parameter, stenosis length and stenosis size have been shown graphically
Hassan, Mohsan; Faisal, Abrar; Bhatti, Muhammad Mubashir
2018-02-01
Polyvinyl alcohol (PVA) is an important industrial chemical, which is used in numerous chemical engineering applications. It is important to study and predict the flow behavior of PVA solutions and the role of nanoparticles in heat transfer applications to be used in chemical processes on industrial scale. Therefore, the present study deals with the PVA solution-based non-Newtonian Al2O3-nanofluid flow along with heat transfer over wedge. The power-law model is used for this non-Newtonian nanofluid which exhibited shear-thinning behavior. The influences of PVA and nanoparticles concentrations on the characteristics of velocity and temperature profiles are examined graphically. The impacts of these parameters on wall shear stress and convective heat transfer coefficient are also studied through tabular form. During the numerical computations, the impacts of these parameters on flow index and consistency index along with other physical properties of nanofluid are also considered. In this study, we found an improvement in heat transfer and temperature profile of fluid by distribution of Al2O3 nanoparticles. It is also noticed that resistance between adjacent layers of moving fluid is enhanced due to these nanoparticles which leads to decline in velocity profile and increases in shear stress at wall.
Boundary Value Problems and Approximate Solutions
African Journals Online (AJOL)
Tadesse
Department of Mathematics, College of Natural and Computational Scineces, Mekelle ..... In this section, the Variational Iteration Method is applied to different forms of .... Some problems in non-Newtonian fluid mechanics, Ph.D. thesis, Wales.
On the analytic solution of the steady flow of a fourth grade fluid
International Nuclear Information System (INIS)
Sajid, M.; Hayat, T.; Asghar, S.
2006-01-01
The steady flow of a fourth grade fluid is a problem belonging to non-Newtonian fluid mechanics and deserves to be more widely studied than it has been to date. In the non-linear regime the literature is scarce. We develop a formulation suitable for solution of hydrodynamic equation containing non-linear rheological effects of fourth grade fluids. The homotopy analysis method (HAM) is used to investigate the flow of a fourth grade fluid past a porous plate. Explicit analytic solution is given. The non-linear effects on the velocity distribution is shown and discussed. Comparison of the present analysis is also made with the existing results in the literature
Directory of Open Access Journals (Sweden)
M.B. Riaz
2016-12-01
Full Text Available The aim of this article was to analyze the rotational flow of an Oldroyd-B fluid with fractional derivatives, induced by an infinite circular cylinder that applies a constant couple to the fluid. Such kind of problem in the settings of fractional derivatives has not been found in the literature. The solutions are based on an important remark regarding the governing equation for the non-trivial shear stress. The solutions that have been obtained satisfy all imposed initial and boundary conditions and can easily be reduced to the similar solutions corresponding to ordinary Oldroyd-B, fractional/ordinary Maxwell, fractional/ordinary second-grade, and Newtonian fluids performing the same motion. The obtained results are expressed in terms of Newtonian and non-Newtonian contributions. Finally, the influence of fractional parameters on the velocity, shear stress and a comparison between generalized and ordinary fluids is graphically underlined.
Narayanan, C. M.
2014-02-01
Attempts have been made to analyse the momentum and heat transfer characteristics in tortuous flow of non-Newtonian fluids such as suspensions and polymer solutions through tubes of diverging-converging geometry. The results of the study indicate that the transfer coefficients are significantly higher in such systems as compared to the conventional couette flow (through uniform cylindrical tubes). Moreover, the simultaneous increase in pressure drop due to the tortuous wall geometry has been observed to be relatively insignificant. Fluids with different rheological characteristics such as Bingham plastic fluids, pseudoplastic fluids, Ellis model fluids and fluids obeying Reiner-Philippoff rheology have been studied. The specific advantages of these geometries in providing enhanced performance efficiency have been effectively highlighted.
Directory of Open Access Journals (Sweden)
Asma Khalid
2015-01-01
Full Text Available The unsteady free flow of a Casson fluid past an oscillating vertical plate with constant wall temperature has been studied. The Casson fluid model is used to distinguish the non-Newtonian fluid behaviour. The governing partial differential equations corresponding to the momentum and energy equations are transformed into linear ordinary differential equations by using nondimensional variables. Laplace transform method is used to find the exact solutions of these equations. Expressions for shear stress in terms of skin friction and the rate of heat transfer in terms of Nusselt number are also obtained. Numerical results of velocity and temperature profiles with various values of embedded flow parameters are shown graphically and their effects are discussed in detail.
Directory of Open Access Journals (Sweden)
B. Y. Ogunmola
2016-01-01
Full Text Available Regular perturbation technique is applied to analyze the fluid flow and heat transfer in a pipe containing third-grade fluid with temperature-dependent viscosities and heat generation under slip and no slip conditions. The obtained approximate solutions were used to investigate the effects of slip on the heat transfer characteristics of the laminar flow in a pipe under Reynolds’s and Vogel’s temperature-dependent viscosities. Also, the effects of parameters such as variable viscosity, non-Newtonian parameter, viscous dissipation, and pressure gradient at various values were established. The results of this work were compared with the numerical results found in literature and good agreements were established. The results can be used to advance the analysis and study of the behavior of third-grade fluid flow and steady state heat transfer processes such as those found in coal slurries, polymer solutions, textiles, ceramics, catalytic reactors, and oil recovery applications.
Directory of Open Access Journals (Sweden)
Aftab Ahmed
2018-01-01
Full Text Available The aim of the present study is to investigate the combined effects of the thermal radiation, viscous dissipation, suction/injection and internal heat generation/absorption on the boundary layer flow of a non-Newtonian power law fluid over a semi infinite permeable flat plate moving in parallel or reversely to a free stream. The resulting system of partial differential equations (PDEs is first transformed into a system of coupled nonlinear ordinary differential equations (ODEs which are then solved numerically by using the shooting technique. It is found that the dual solutions exist when the flat plate and the free stream move in the opposite directions. Dimensionless boundary layer velocity and temperature distributions are plotted and discussed for various values of the emerging physical parameters. Finally, the tables of the relevant boundary derivatives are presented for some values of the governing physical parameters.
Farsiani, Yasaman; Elbing, Brian
2015-11-01
Adding trace amounts of long chain polymers into a liquid flow is known to reduce skin friction drag by up to 80%. While polymer drag reduction (PDR) has been successfully implemented in internal flows, diffusion and degradation have limited its external flow applications. A weakness in many previous PDR studies is that there was no characterization of the polymer being injected into the turbulent boundary layer, which can be accomplished by testing a sample in a pressure-drop tube. An implicit assumption in polymer characterization is that the flow is fully developed at the differential pressure measurement. While available data in the literature shows that the entry length to achieve fully developed flow increases with polymeric solutions, it is unclear how long is required to achieve fully developed flow for non-Newtonian turbulent flows. In the present study, the pressure-drop is measured across a 1.05 meter length section of a 1.04 cm inner diameter pipe. Differential pressure is measured with a pressure transducer for different entry lengths, flow and polymer solution properties. This presentation will present preliminary data on the required entrance length as well as characterization of polymer solution an estimate of the mean molecular weight.
On the role of specific interactions in the diffusion of nanoparticles in aqueous polymer solutions.
Mun, Ellina A; Hannell, Claire; Rogers, Sarah E; Hole, Patrick; Williams, Adrian C; Khutoryanskiy, Vitaliy V
2014-01-14
Understanding nanoparticle diffusion within non-Newtonian biological and synthetic fluids is essential in designing novel formulations (e.g., nanomedicines for drug delivery, shampoos, lotions, coatings, paints, etc.), but is presently poorly defined. This study reports the diffusion of thiolated and PEGylated silica nanoparticles, characterized by small-angle neutron scattering, in solutions of various water-soluble polymers such as poly(acrylic acid) (PAA), poly(N-vinylpyrrolidone) (PVP), poly(ethylene oxide) (PEO), and hydroxyethylcellulose (HEC) probed using NanoSight nanoparticle tracking analysis. Results show that the diffusivity of nanoparticles is affected by their dimensions, medium viscosity, and, in particular, the specific interactions between nanoparticles and the macromolecules in solution; strong attractive interactions such as hydrogen bonding hamper diffusion. The water-soluble polymers retarded the diffusion of thiolated particles in the order PEO > PVP > PAA > HEC whereas for PEGylated silica particles retardation followed the order PAA > PVP = HEC > PEO. In the absence of specific interactions with the medium, PEGylated nanoparticles exhibit enhanced mobility compared to their thiolated counterparts despite some increase in their dimensions.
International Nuclear Information System (INIS)
Hemaka Bandalusena, H C; Zimmerman, William B; Rees, Julia M
2009-01-01
The main purpose of this study is to model non-Newtonian fluid flows in microgeometries. Velocity fields of dilute xanthan gum solutions in a microfluidic T-junction have been measured for pressure-driven flow using micron resolution particle image velocimetry (µ-PIV). Xanthan gum at a fixed concentration is a power-law fluid. Varying the concentration changes the rheology, effectively altering the power-law parameters reflecting the changes in the fluid's shear response since viscoelasticity and extensional viscosity are negligible for dilute solutions of this substance. As the flow is forced to turn the corner of the T-junction, a range of shear rates, and hence viscosities, is produced. If this feature could be incorporated into a viscometer, then potentially the constitutive parameters of a complex fluid could be ascertained from a single experiment. A mathematical model based on a finite element technique has been developed to simulate the fluid flow in the experimental system. Model predictions of the velocity field are found to agree well (less than 5% error) with observations, thus validating the model
Validation of computational non-Newtonian fluid model for membrane bioreactor
DEFF Research Database (Denmark)
Sørensen, Lasse; Bentzen, Thomas Ruby; Skov, Kristian
2015-01-01
Membrane bioreactor (MBR) systems are often considered as the wastewater treatment method of the future due to its high effluent quality. One of the main problems with such systems is a relative large energy consumption, which has led to research in this specific area. A powerful tool for optimiz......Membrane bioreactor (MBR) systems are often considered as the wastewater treatment method of the future due to its high effluent quality. One of the main problems with such systems is a relative large energy consumption, which has led to research in this specific area. A powerful tool...
Entropy generation in a pipe due to non-Newtonian fluid flow ...
Indian Academy of Sciences (India)
pipes. They indicated that although the power-law model adequately agreed with the shear stress and shear rate ... In this case, it was shown that the power-law model was not capable of predicting the nor- mal stress effects that .... The dimensional volumetric entropy generation is defined as (Bejan 1995):. Sgen = k. ¯θ2. 0.
Non-Newtonian fluid flow in annular pipes and entropy generation ...
Indian Academy of Sciences (India)
Author Affiliations. M Yürüsoy1 B S Yilbaş2 M Pakdemirli2. Technical Education Faculty, Afyon Kocatepe University, Afyon, Turkey; Department of Mechanical Engineering, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia ...
Stronger constraints on non-Newtonian gravity from the Casimir effect
Energy Technology Data Exchange (ETDEWEB)
Mostepanenko, V M; Klimchitskaya, G L [Center of Theoretical Studies and Institute for Theoretical Physics, Leipzig University, D-04009, Leipzig (Germany); Decca, R S [Department of Physics, Indiana University-Purdue University Indianapolis, Indianapolis, IN 46202 (United States); Fischbach, E; Krause, D E [Department of Physics, Purdue University, West Lafayette, IN 47907 (United States); Lopez, D [Bell Laboratories, Lucent Technologies, Murray Hill, NJ 07974 (United States)
2008-04-25
We review new constraints on the Yukawa-type corrections to Newtonian gravity obtained recently from gravitational experiments and from the measurements of the Casimir force. Special attention is paid to the constraints following from the most precise dynamic determination of the Casimir pressure between the two parallel plates by means of a micromechanical torsional oscillator. The possibility of setting limits on the predictions of chameleon field theories using the results of gravitational experiments and Casimir force measurements is discussed.
Three-dimensional stability, receptivity and sensitivity of non-Newtonian flows inside open cavities
International Nuclear Information System (INIS)
Citro, Vincenzo; Giannetti, Flavio; Pralits, Jan O
2015-01-01
We investigate the stability properties of flows over an open square cavity for fluids with shear-dependent viscosity. Analysis is carried out in context of the linear theory using a normal-mode decomposition. The incompressible Cauchy equations, with a Carreau viscosity model, are discretized with a finite-element method. The characteristics of direct and adjoint eigenmodes are analyzed and discussed in order to understand the receptivity features of the flow. Furthermore, we identify the regions of the flow that are more sensitive to spatially localized feedback by building a spatial map obtained from the product between the direct and adjoint eigenfunctions. Analysis shows that the first global linear instability of the steady flow is a steady or unsteady three-dimensionl bifurcation depending on the value of the power-law index n. The instability mechanism is always located inside the cavity and the linear stability results suggest a strong connection with the classical lid-driven cavity problem. (paper)
Study of blades inclination influence of gate impeller with a non-Newtonian fluid of Bingham
Directory of Open Access Journals (Sweden)
Rahmani Lakhdar
2016-01-01
Full Text Available A large number of chemical operations, biochemical or petrochemical industry is very depending on the rheological fluids nature. In this work, we study the case of highly viscous of viscoplastic fluids in a classical system of agitation: a cylindrical tank with plate bottom without obstacles agitated by gate impeller agitator. We are interested to the laminar, incompressible and isothermal flows. We devote to a numerical approach carried out using an industrial code CFD Fluent 6.3.26 based on the method of finites volumes discretization of Navier - Stokes equations formulated in variables (U.V.P. The threshold of flow related to the viscoplastic behavior is modeled by a theoretical law of Bingham. The results obtained are used to compare between the five configurations suggested of power consumption. We study the influence of inertia by the variation of Reynolds number.
Shape optimization for non-Newtonian fluids in time-dependent domains
Czech Academy of Sciences Publication Activity Database
Sokolowski, J.; Stebel, Jan
2014-01-01
Roč. 3, č. 2 (2014), s. 331-348 ISSN 2163-2480 R&D Projects: GA ČR GA201/09/0917 Institutional support: RVO:67985840 Keywords : shape optimization * time - dependent domain * incompressible viscous fluid Subject RIV: BA - General Mathematics Impact factor: 0.373, year: 2014 http://www.aimsciences.org/journals/home.jsp?journalID=25
Shape sensitivity analysis of time-dependent flows of incompressible non-Newtonian fluids
Czech Academy of Sciences Publication Activity Database
Sokolowski, J.; Stebel, Jan
2011-01-01
Roč. 40, č. 4 (2011), s. 1077-1097 ISSN 0324-8569 R&D Projects: GA ČR GA201/09/0917 Institutional research plan: CEZ:AV0Z10190503 Keywords : shape optimization * shape gradient * incompressible viscous fluid Subject RIV: BA - General Mathematics Impact factor: 0.300, year: 2010
Numerical Modelling of Non-Newtonian Fluid in a Rotational Cross-Flow MBR
DEFF Research Database (Denmark)
Bentzen, Thomas Ruby; Ratkovic, Nicolas Rios; Rasmussen, Michael R.
2011-01-01
Fouling is the main bottleneck of the widespread of MBR systems. One way to decrease and/or control fouling is by process hydrodynamics. This can be achieved by the increase of liquid crossflow velocity. In rotational cross-flow MBR systems, this is attained by the spinning of e.g. impellers. Val...
Deposition Velocities of Non-Newtonian Slurries in Pipelines: Complex Simulant Testing
Energy Technology Data Exchange (ETDEWEB)
Poloski, Adam P.; Bonebrake, Michael L.; Casella, Andrew M.; Johnson, Michael D.; Toth, James J.; Adkins, Harold E.; Chun, Jaehun; Denslow, Kayte M.; Luna, Maria; Tingey, Joel M.
2009-07-01
One of the concerns expressed by the External Flowsheet Review Team (EFRT) is about the potential for pipe plugging at the Waste Treatment and Immobilization Plant (WTP). Per the review’s executive summary, “Piping that transports slurries will plug unless it is properly designed to minimize this risk. This design approach has not been followed consistently, which will lead to frequent shutdowns due to line plugging.” To evaluate the potential for plugging, deposition-velocity tests were performed on several physical simulants to determine whether the design approach is conservative. Deposition velocity is defined as the velocity below which particles begin to deposit to form a moving bed of particles on the bottom of a straight horizontal pipe during slurry-transport operations. The deposition velocity depends on the system geometry and the physical properties of the particles and fluid. An experimental program was implemented to test the stability-map concepts presented in WTP-RPT-175 Rev. 01. Two types of simulant were tested. The first type of simulant was similar to the glass-bead simulants discussed in WTP-RPT-175 Rev. 0 ; it consists of glass beads with a nominal particle size of 150 µm in a kaolin/water slurry. The initial simulant was prepared at a target yield stress of approximately 30 Pa. The yield stress was then reduced, stepwise, via dilution or rheological modifiers, ultimately to a level of <1 Pa. At each yield-stress step, deposition-velocity testing was performed. Testing over this range of yield-stress bounds the expected rheological operating window of the WTP and allows the results to be compared to stability-map predictions for this system. The second simulant was a precipitated hydroxide that simulates HLW pretreated sludge from Hanford waste tank AZ-101. Testing was performed in a manner similar to that for the first simulant over a wide range of yield stresses; however, an additional test of net-positive suction-head required (NPSHR) was performed at each yield stress condition. Unlike the previous simulant, the sizes and densities of the particles that can deposit in the piping are a result of the simulant precipitation process; there is expected to be a complex mixture of particles of various sizes and densities that make it difficult to predict a stability map. The objective of the testing is to observe whether behavior consistent with the stability-map concept occurs in complex simulants with mixtures of different sizes and densities.
The Effect of Polymer Content on the Non-Newtonian Behavior of Acetaminophen Suspension
Directory of Open Access Journals (Sweden)
Eskandar Moghimipour
2013-01-01
Full Text Available Acetaminophen is used as an analgesic and antipyretic agent. The aim of the study was evaluation of the effect of different polymers on rheological behavior of acetaminophen suspension. In order to achieve controlled flocculation, sodium chloride was added. Then structural vehicles such as carboxymethyl cellulose (CMC, polyvinyl pyrrolidone (PVP, tragacanth, and magnesium aluminum silicate (Veegum were evaluated individually and in combination. Physical stability parameters such as sedimentation volume (F, redispersibility (n, and growth of crystals of the suspensions were determined. Also, the rheological properties of formulations were studied. The results of this study showed that the combination of suspending agents had the most physical stability and pseudoplastic behavior with some degree of thixotropy. Viscosity of suspensions was increased by adding NaCl 0.02%. Presence of PVP is necessary for improving rheological behavior of suspensions by NaCl. This may be related to the cross-linking between the carbonyl group in the PVP segment and Na+ ions.
Flow of a non-Newtonian fluid through channels with permeable wall
Energy Technology Data Exchange (ETDEWEB)
Martins-Costa, Maria Laura [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Engenharia Mecanica. Lab. de Matematica Teorica e Aplicada]. E-mail: laura@mec.uff.br; Gama, Rogerio M. Saldanha da [Laboratorio Nacional de Computacao Cientifica (LNCC), Petropolis, RJ (Brazil)]. E-mail: rsgama@domain.com.br; Frey, Sergio [Rio Grande do Sul Univ., Porto Alegre, RS (Brazil). Dept. de Engenharia Mecanica. Grupo de Estudos Termicos e Energeticos
2000-07-01
In the present work the momentum transport in two adjacent flow regions is described by means of a continuum theory of mixtures, specially developed to model multiphase phenomena. A generalized Newtonian fluid flows through the permeable wall channel, originating a pure fluid region and a mixture region - where the fluid saturates the porous matrix. The fluid and the porous matrix are treated as continuous constituents of a binary mixture coexisting superposed, each of them occupying simultaneously the whole volume of the mixture. An Ostwald-de Waele behavior is assumed for both the fluid constituent (in the mixture region) and the fluid (in the so-called pure fluid region), while the porous matrix, represented by the solid constituent, is assumed rigid, homogeneous, isotropic and at rest. Compatibility conditions at the interface (pure fluid-mixture) for momentum transfer are proposed and discussed. Assuming no flow across the interface, the velocity should be zero on the solid parts of the boundary and should match the fluid diffusing velocity on the fluid parts of the boundary. Also the shear stress at the pure fluid region is to be balanced by a multiple of the partial shear stress at the mixture region. A minimum principle for the above-described problem, assuming fully developed flow in both regions, is presented, providing an easy and reliable way for carrying out numerical simulations. (author)
Combinatorial Optimization for Energy Saving in Nickel Industry Non-Newtonian Fluid Pumping System
International Nuclear Information System (INIS)
Hernández Ramírez, Gabriel; Legra Lobaina, Aristides; Columbié Navarro, Angel; Marcos Aníbal León Segovia
2017-01-01
In the present work a study of the influence of the rheological parameters of the lateritic hydromixtures with the energetic ones of the pumping systems that guarantee the productivity of nickel company 'Commander Pedro Sotto Alba' is carried out. From an experimental study and through an estimator, the rheological parameters are modeled as a function of the factors: temperature, solids content, chemical and granulometric composition. From an appropriate discretization of the model of the lateritic hydrometer pumping system and the application of a Discrete Combination Optimization Double Sequencing procedure, the operating parameters of this system were obtained, in order to guarantee a flow rate of 1600 m3 / h and one Adequate solids concentration. It is concluded that the use of a mathematical model that relates the rheological parameters of the lateritic pulp and the energy parameters of the pumping system, guarantee the metallurgical and energy efficiency in the acid leaching process with an average increase in production between 1000-1500 T Ni + Co / y and an energy saving of 30 MWh /year. (author)
Entropy generation in a pipe due to non-Newtonian fluid flow ...
Indian Academy of Sciences (India)
2016-08-26
Aug 26, 2016 ... Author Affiliations. M Pakdemirli1 B S Yilbas2. Department of Mechanical Engineering, Celal Bayar University, Manisa, Turkey; Department of Mechanical Engineering, King Fahd University of Petroleum and Minerals, P.O. Box 1913, Dhahran 31261, Saudi Arabia ...
Lie group analysis of flow and heat transfer of non-Newtonian ...
Indian Academy of Sciences (India)
2017-01-09
Jan 9, 2017 ... of its industrial and engineering applications. In view of all these ... fluids). Applying nanotechnology to heat transfer, the new concept of ..... The set of nonlinear ordinary differential equations of. (28) and (32) subject to the ...
Physics of Non-Newtonian Fluids and Interdisciplinary Relations (Biology and Criminology)
Holubova, R.
2018-01-01
The aim of the paper is the presentation of an interdisciplinary topic that allows applying content knowledge in physics, mathematics and biology in real life environment. Students use to play games and view crime scenes but in common they have little knowledge about the science used during crime scene investigation. In this paper the science…
Numerical Modeling of the Side Flow in Tape Casting of a Non-Newtonian Fluid
DEFF Research Database (Denmark)
Jabbari, Masoud; Hattel, Jesper Henri
2013-01-01
in the tape casting process is modeled numerically with ANSYS FLUENT in combination with an Ostwald-de Waele power law constitutive equation. Based on rheometer experiments, the constants in the Ostwald-de Waele power law are identified for the considered LSM material and applied in the numerical modeling......One of the most common ways used to produce multilayer ceramics (MLC) is tape casting. In this process, the dried tape thickness is of great interest to control the desired products and applications. One of the parameters that influences the final tape thickness is the side flow factor (a) which...... is mostly measured at the end of the process by a volumetric comparison of the tape which flowed outside the casting width to the tape within the casting width. This phenomenon has not been predicted theoretically yet in the literature. In this study, the flow of (La0.85Sr0.15)0.9MnO3 (LSM) slurry...
The Effect of Polymer Content on the Non-Newtonian Behavior of Acetaminophen Suspension
Moghimipour, Eskandar; Kouchak, Maryam; Salimi, Anayatollah; Bahrampour, Saeed; Handali, Somayeh
2013-01-01
Acetaminophen is used as an analgesic and antipyretic agent. The aim of the study was evaluation of the effect of different polymers on rheological behavior of acetaminophen suspension. In order to achieve controlled flocculation, sodium chloride was added. Then structural vehicles such as carboxymethyl cellulose (CMC), polyvinyl pyrrolidone (PVP), tragacanth, and magnesium aluminum silicate (Veegum) were evaluated individually and in combination. Physical stability parameters such as sedimentation volume (F), redispersibility (n), and growth of crystals of the suspensions were determined. Also, the rheological properties of formulations were studied. The results of this study showed that the combination of suspending agents had the most physical stability and pseudoplastic behavior with some degree of thixotropy. Viscosity of suspensions was increased by adding NaCl 0.02%. Presence of PVP is necessary for improving rheological behavior of suspensions by NaCl. This may be related to the cross-linking between the carbonyl group in the PVP segment and Na+ ions. PMID:24109512
Break-up of a non-Newtonian jet injected downwards in a ...
Indian Academy of Sciences (India)
2Department of Chemical Engineering, Indian Institute of Technology Bombay,. Powai, Mumbai ... (Cramer et al 2004) has diverse applications in chemical, pharmaceutical, food and cosmetic industries. A wide ...... Ph.D Thesis, IIT Bombay.
Shape optimization for non-Newtonian fluids in time-dependent domains
Czech Academy of Sciences Publication Activity Database
Sokolowski, J.; Stebel, Jan
2014-01-01
Roč. 3, č. 2 (2014), s. 331-348 ISSN 2163-2480 R&D Projects: GA ČR GA201/09/0917 Institutional support: RVO:67985840 Keywords : shape optimization * time-dependent domain * incompressible viscous fluid Subject RIV: BA - General Mathematics Impact factor: 0.373, year: 2014 http://www.aimsciences.org/journals/home.jsp?journalID=25
Was Newton right? A search for non-Newtonian behavior of weak-field gravity
Directory of Open Access Journals (Sweden)
Boynton Paul
2014-06-01
Full Text Available Empirical tests of Einstein’s metric theory of gravitation, even in the non-relativistic, weak-field limit, could play an important role in judging theory-driven extensions of the current Standard Model of fundamental interactions. Guided by Galileo's work and his own experiments, Newton formulated a theory of gravity in which the force of attraction between two bodies is independent of composition and proportional to the inertia of each, thereby transparently satisfying Galileo's empirically informed conjecture regarding the Universality of Free Fall. Similarly, Einstein honored the manifest success of Newton’s theory by assuring that the linearized equations of GTR matched the Newtonian formalism under “classical” conditions. Each of these steps, however, was explicitly an approximation raised to the status of principle. Perhaps, at some level, Newtonian gravity does not accurately describe the physical interaction between uncharged, unmagnetized, macroscopic bits of ordinary matter. What if Newton were wrong? Detecting any significant deviation from Newtonian behavior, no matter how small, could provide new insights and possibly reveal new physics. In the context of physics as an empirical science, for us this yet unanswered question constitutes sufficient motivation to attempt precision measurements of the kind described here. In this paper we report the current status of a project to search for violation of the Newtonian inverse square law of gravity.
Fractional Flow Theory Applicable to Non-Newtonian Behavior in EOR Processes
Rossen, W.R.; Venkatraman, A.; Johns, R.T.; Kibodeaux, K.R.; Lai, H.; Moradi Tehrani, N.
2011-01-01
The method of characteristics, or fractional-flow theory, is extremely useful in understanding complex Enhanced Oil Recovery (EOR) processes and in calibrating simulators. One limitation has been its restriction to Newtonian rheology except in rectilinear flow. Its inability to deal with
International Nuclear Information System (INIS)
Narayan, A.P.; Rainwater, J.C.; Hanley, H.J.M.
1995-01-01
A study of the Weissenberg effect (rod climbing in a stirred system) based on nonequilibrium molecular dynamics (NEMD) is reported. Simulation results from a soft-sphere fluid are used to obtain a self-consistent free-surface profile of the fluid of finite compressibility undergoing Couette flow between concentric cylinders. A numerical procedure is then applied to calculate the height profile for a hypothetical fluid with thermophysical properties of the soft-sphere liquid and of a dense colloidal suspension. The height profile calculated is identified with shear thickening and the forms of the viscometric functions. The maximum climb occurs between the cylinders rather than at the inner cylinder
International Nuclear Information System (INIS)
Slatter, P.T.
1986-09-01
The novel Balanced Beam Tube Viscometer (BBTV), developed at the University of Cape Town, has been further developed and refined. Extensive work has been done in the following areas: (i) The effective length of BBTV tubes. (ii) Interpretation of the data obtained using the BBTV in both the laminar and turbulent flow regimes. (iii) Comparison with the rotary type viscometer. Kaolin clay and uranium tailings, slimes and slurries of different particle size range and concentration have been successfully characterised by yield-pseudoplastic rheologies using the BBTV. The BBTV is in fact a miniature pipeline and it has been shown that it is capable of producing valid turbulent flow data and indicating the laminar/turbulent transition region in the two tube sizes
Georgievskii, D. V.; Israilov, M. Sh.
2015-07-01
In the problems of common vibrations of extended underground structures (pipelines and tunnels) and soil, an approach of the one-dimensional deformation of the medium is developed; this approach is based on the assumption that the soil deformation in the direction of seismic wave propagation coinciding with the pipeline axis is prevailing. The analytic solutions are obtained in the cases where the wave velocity in the soil is respectively less or greater than the wave velocity in the pipeline. The parameters influencing the pipeline fracture are revealed and methods for increasing the seismic stability of such structures are given. The possibility of the pipeline fatigue fracture is pointed out. The statements and solutions of parabolic problems modeling the physical phenomena in soils in the case of discontinuous velocity on the boundaries at the initial time are given. The notion of generalized vorticity diffusion is introduced and the cases of self-similarity existence are classified. A detailed analysis is performed for the non-Newtonian polynomial fluid, the medium close in properties to the rigidly ideally plastic body, and the viscoplastic Shvedov—Bingham body. In the case of physically linear medium, new self-similar solutions are obtained which describe the process of unsteady axially symmetric shear in spherical coordinates. The first approximation to the asymptotic solution of the problem of the vortex sheet diffusion is constructed in a medium with small polynomial nonlinearity. The solutions polynomially decreasing to zero as the self-similar variable increases are proposed in the class of two-constant fluids.
Front‐tracking simulations of bubbles rising in non‐Newtonian fluids
Battistella, Alessandro; Van Schijndel, J.G.; Baltussen, Maike W.
2017-01-01
In the wide and complex field of multiphase flows, bubbly flows with non-Newtonian liquids are encountered in several important applications, such as in polymer solutions or fermentation broths. Despite the widespread application of non-Newtonian liquids, most of the models and closures used in industry are valid for Newtonian fluids only, if not even restricted to air-water systems. However, it is well known that the non-Newtonian rheology significantly influences the liquid and bubble behav...
Energy Technology Data Exchange (ETDEWEB)
Sharipov, A U; Yangirov, I Z
1982-01-01
A clay-powder, cement, and water-base plugging solution is proposed having reduced solution viscosity characteristics while maintaining tensile strength in cement stone. This solution utilizes silver graphite and its ingredients, by mass weight, are as follows: cement 51.2-54.3%; claypowder 6.06-9.1%; silver graphite 0.24-0.33%; with water making up the remainder.
International Nuclear Information System (INIS)
Seitz, M.G.
1982-01-01
Reviewed in this statement are methods of preparing solutions to be used in laboratory experiments to examine technical issues related to the safe disposal of nuclear waste from power generation. Each approach currently used to prepare solutions has advantages and any one approach may be preferred over the others in particular situations, depending upon the goals of the experimental program. These advantages are highlighted herein for three approaches to solution preparation that are currently used most in studies of nuclear waste disposal. Discussion of the disadvantages of each approach is presented to help a user select a preparation method for his particular studies. Also presented in this statement are general observations regarding solution preparation. These observations are used as examples of the types of concerns that need to be addressed regarding solution preparation. As shown by these examples, prior to experimentation or chemical analyses, laboratory techniques based on scientific knowledge of solutions can be applied to solutions, often resulting in great improvement in the usefulness of results
DEFF Research Database (Denmark)
Ratkovich, Nicolas Rios; Bentzen, Thomas Ruby; Majumder, S.
Gas-liquid two-phase flows are presented everywhere in industrial processes (i.e. gas-oil pipelines). In spite of the common occurrence of these two-phase flows, their understanding is limited compared to single-phase flows. Different studies on two-phase flow have focus on developing empirical...... in the literature but none of them is enough robust and suitable for different conditions (i.e. flow patterns, gas-liquid combinations, pipe inclination angles, etc.). This clearly represents a drawback and more research in required on this field....... correlations based on large sets of experiment data for void fraction [1,2] and pressure drop [3,4] which have proven to be accurate for the specific condition that their where developed for. Currently, dozens of void fraction and pressure drop correlations for different flow patterns are available...
DEFF Research Database (Denmark)
Svec, Oldrich; Skoček, Jan
2013-01-01
The ability of the Lattice Boltzmann method, as the fluid dynamics solver, to properly simulate macroscopic Navier’s slip boundary condition is investigated. An approximate equation relating the Lattice Boltzmann variable slip boundary condition with the macroscopic Navier’s slip boundary condition...
Energy Technology Data Exchange (ETDEWEB)
Klimchitskaya, G.L. [Central Astronomical Observatory at Pulkovo of the Russian Academy of Sciences, Saint Petersburg (Russian Federation); Peter the Great Saint Petersburg Polytechnic University, Institute of Physics, Nanotechnology and Telecommunications, Saint Petersburg (Russian Federation)
2017-05-15
The strongest constraints on the Yukawa-type corrections to Newton's gravitational law and on the coupling constants of axion-like particles to nucleons, following from recently performed experiments of Casimir physics, are presented. Specifically, the constraints obtained from measurements of the lateral and normal Casimir forces between sinusoidally corrugated surfaces, and from the isoelectronic experiment are considered, and the ranges of their greatest strength are refined. Minor modifications in the experimental setups are proposed which allow for strengthening the resultant constraints up to an order of magnitude. The comparison with some weaker constraints derived in the Casimir regime is also made. (orig.)
DEFF Research Database (Denmark)
Bentzen, Thomas Ruby; Ratkovich, Nicolas Rios; Madsen, S.
2012-01-01
Fouling is the main bottleneck of the widespread use of MBR systems. One way to decrease and/or control fouling is by process hydrodynamics. This can be achieved by the increase of liquid cross- ﬂow velocity. In rotational cross-ﬂow MBR systems, this is attained by the spinning of, for example, i......-weighted average shear stress was developed for water and AS as a function of the angular velocity and the total suspended solids concentration. These relationships can be linked to the energy consumption of this type of systems.......Fouling is the main bottleneck of the widespread use of MBR systems. One way to decrease and/or control fouling is by process hydrodynamics. This can be achieved by the increase of liquid cross- ﬂow velocity. In rotational cross-ﬂow MBR systems, this is attained by the spinning of, for example......, impellers. Validation of the CFD (computational ﬂuid dynamics) model was made against laser Doppler anemometry (LDA) tangential velocity measurements (error less than 8%) using water as a ﬂuid. The shear stress over the membrane surface was inferred from the CFD simulations for water. However, activated...
A wall boundary condition for the simulation of a turbulent non-Newtonian domestic slurry in pipes
Mehta, D.; Thota Radhakrishnan, A.K.; van Lier, J.B.; Clemens, F.H.L.R.
2018-01-01
The concentration (using a lesser amount of water) of domestic slurry promotes resource recovery (nutrients and biomass) while saving water. This article is aimed at developing numerical methods to support engineering processes such as the design and implementation of sewerage for concentrated
Peron, Roberto; Lucchesi, David
The pericenter shift of a binary system represents a suitable observable to be used to test for possible deviations from the Newtonian gravitational inverse—square—law in favor of pos-sible new weak interactions between macroscopic objects. These very weak and long-range interactions are usually described by means of a Yukawa—like potential with strength α and range λ. Moreover, these supplementary interactions may be either consistent with Einstein Equivalence Principle or not. In this work, we analyzed 11 years of LAGEOS II normal points using the GEODYN II code with suitable models for both gravitational and non—gravitational perturbations. However, we do not included in the models the general relativity corrections to Newtonian gravity, such as the ones due to the Earth's gravitoelectric and gravitomagnetic fields. From the fit of the satellite pericenter residuals we have been able to obtain a 99% agreement with the predictions of Einstein theory of gravitation. Therefore, the present mea-surement of the LAGEOS II pericenter shift represents a 1% measurement in the field of the Earth of the combination of the Parametrized Post—Newtonian parameters g and b of general relativity. This result may be also used to put limits on the strength α of a possible Yukawa— like interaction with a characteristic range of about 1 Earth radii. We obtained |α| ≈ 4 · 10-11 , that represents a significant improvement with respect to the previous constraints based on Earth—LAGEOS or Lunar—LAGEOS data.
Sonneveld, C.; Voogt, W.
2009-01-01
The characteristics of the soil solution in the root environment in the greenhouse industry differ much from those for field grown crops. This is caused firstly by the growing conditions in the greenhouse, which strongly differ from those in the field and secondly the function attributed to the soil
International Development Research Centre (IDRC) Digital Library (Canada)
The Crucible Group operates on the basis of good faith –– producing best effort non-consensus texts. ..... science and technology-based solutions to agricultural production constraints, it is ...... In 1997 researchers at Case Western Reserve Medical School in Ohio (US) ...... Is there a need to update the system-wide IP audit?
Annevelink, E.; Bos, H.L.; Meesters, K.P.H.; Oever, van den M.J.A.; Haas, de W.; Kuikman, P.J.; Rietra, R.P.J.J.; Sikirica, N.
2016-01-01
The fifth part of this report on Circular Solutions is about the circular principle From Waste to Resource. The purpose of this study is to select promising options for the implementation of this circular principle and to elaborate these options further.
Geoghegan, Michael W
2005-01-01
Podcasting is the art of recording radio show style audio tracks, then distributing them to listeners on the Web via podcasting software such as iPodder. From downloading podcasts to producing a track for fun or profit, ""Podcast Solutions"" covers the entire world of podcasting with insight, humor, and the unmatched wisdom of experience.
DEFF Research Database (Denmark)
Efeoglu, Arkin; Møller, Charles; Serie, Michel
2013-01-01
This paper outlines an artifact building and evaluation proposal. Design Science Research (DSR) studies usually consider encapsulated artifact that have relationships with other artifacts. The solution prototype as a composed artifact demands for a more comprehensive consideration in its systematic...... environment. The solution prototype that is composed from blending product and service prototype has particular impacts on the dualism of DSR’s “Build” and “Evaluate”. Since the mix between product and service prototyping can be varied, there is a demand for a more agile and iterative framework. Van de Ven......’s research framework seems to fit this purpose. Van de Ven allows for an iterative research approach to problem solving with flexible starting point. The research activity is the result between the iteration of two dimensions. This framework focuses on the natural evaluation, particularly on ex...
Development and In vitro Evaluation of Betahistine Adhesive-Type ...
African Journals Online (AJOL)
Purpose: To develop a transdermal betahistine (BTH) delivery system using different pressure sensitive adhesives (PSAs) including acrylics, polyisobutylene and styrenic rubber solution. Methods: Formulations were prepared by solvent casting and adhesive transfer method. PSAs - acrylate vinylacetate (AVA), hydrophilic ...
Lauriola, I.; Felisa, G.; Petrolo, D.; Di Federico, V.; Longo, S.
2018-05-01
We present an investigation on the combined effect of fluid rheology and permeability variations on the propagation of porous gravity currents in axisymmetric geometry. The fluid is taken to be of power-law type with behaviour index n and the permeability to depend from the distance from the source as a power-law function of exponent β. The model represents the injection of a current of non-Newtonian fluid along a vertical bore hole in porous media with space-dependent properties. The injection is either instantaneous (α = 0) or continuous (α > 0). A self-similar solution describing the rate of propagation and the profile of the current is derived under the assumption of small aspect ratio between the current average thickness and length. The limitations on model parameters imposed by the model assumptions are discussed in depth, considering currents of increasing/decreasing velocity, thickness, and aspect ratio, and the sensitivity of the radius, thickness, and aspect ratio to model parameters. Several critical values of α and β discriminating between opposite tendencies are thus determined. Experimental validation is performed using shear-thinning suspensions and Newtonian mixtures in different regimes. A box filled with ballotini of different diameter is used to reproduce the current, with observations from the side and bottom. Most experimental results for the radius and profile of the current agree well with the self-similar solution except at the beginning of the process, due to the limitations of the 2-D assumption and to boundary effects near the injection zone. The results for this specific case corroborate a general model for currents with constant or time-varying volume of power-law fluids propagating in porous domains of plane or radial geometry, with uniform or varying permeability, and the possible effect of channelization. All results obtained in the present and previous papers for the key parameters governing the dynamics of power-law gravity
Klijn, F.; Slikker, M.; Tijs, S.H.
2000-01-01
In this note we introduce an egalitarian solution, called the dual egalitarian solution, that is the natural counterpart of the egalitarian solution of Dutta and Ray (1989).We prove, among others, that for a convex game the egalitarian solution coincides with the dual egalitarian solution for its
Castellanos, Maria Monica
-angle neutron scattering experiments were used to characterize the antibody aggregates responsible for this non-Newtonian response. From the neutron scattering data, a weak barrier leading to reversible aggregation is identified. Therefore, proteins aggregate weakly after colliding hydrodynamically, unless they find a favorable contact with high binding energy. Two types of antibody aggregates were identified: oligomers with average radius of gyration of ˜10 nm, and fractal aggregates larger than ˜ 0.1 microm formed by a reaction-limited aggregation process. A characteristic upturn in the scattered intensity at low wavevector and a low shear viscosity increase are observed in aggregated protein solutions. These features are removed by filtering with a 0.2 microm filter, which also eliminates the submicron fractal aggregates. Biophysical characterization supports the conclusions from the rheology and neutron scattering experiments. Finally, molecular dynamics simulations were used to understand the effects of disulfide bonds on the conformational stability of serum albumin. Changes in disulfide bonds in the native structure could lead to partial unfolding, and the formation of aggregates through inter-molecular disulfide bonds. Therefore, it is important to understand the role of each disulfide bond on the structure and dynamics of the protein. After removing disulfide bonds, changes occur in the dynamic correlations between different residues, and the secondary and tertiary structure of albumin. However, not all disulfide bonds affect the conformation of the protein, suggesting that other interactions are more relevant to keep the stability in certain regions. Removal of all disulfide bonds using molecular dynamics is proposed as a practical prescreening tool to identify disulfide bonds that are important for the conformational stability. As a result, some disulfide bonds can be mutated without affecting the conformation of the protein.
International Nuclear Information System (INIS)
Papoyan, V.V.
1989-01-01
A Kerr generalized solution for a stationary axially-symmetric gravitational field of rotating self-gravitational objects is given. For solving the problem Einstein equations and their combinations are used. The particular cases: internal and external Schwarzschild solutions are considered. The external solution of the stationary problem is a Kerr solution generalization. 3 refs
International Nuclear Information System (INIS)
Noakes, J.E.; Culp, R.A.
1983-01-01
A radiochromic solution which is sensitive to small dosages of ionizing and ultraviolet radiation is described. It consists of a solution of a leucocyanide dye in a clear polar solvent with enough organic acid added to make the solution at least slightly acidic and responds to radiation by permanently changing color. Up to one half of the solution by weight can be replaced by a second solution of an aromatic solvent and an organic fluor. Another modification of the invention is a solution of a leucocyanide dye in a clear polar solvent having an aromatic group, an organic fluor, and enough organic acid to make the solution at least slightly acidic. (author)
Liquid scintillation solutions
International Nuclear Information System (INIS)
Long, E.C.
1976-01-01
The liquid scintillation solution described includes a mixture of: a liquid scintillation solvent, a primary scintillation solute, a secondary scintillation solute, a variety of appreciably different surfactants, and a dissolving and transparency agent. The dissolving and transparency agent is tetrahydrofuran, a cyclic ether. The scintillation solvent is toluene. The primary scintillation solute is PPO, and the secondary scintillation solute is dimethyl POPOP. The variety of appreciably different surfactants is composed of isooctylphenol-polyethoxyethanol and sodium dihexyl sulphosuccinate [fr
Naz, Muhammad Yasin; Sulaiman, Shaharin Anwar; Ariwahjoedi, Bambang
2015-02-07
Spray coating technology has demonstrated great potential in the slow release fertilizers industry. The better understanding of the key spray parameters benefits both the environment and low cost coating processes. The use of starch based materials to coat the slow release fertilizers is a new development. However, the hydraulic spray jet breakup of the non-Newtonian starchy solutions is a complex phenomenon and very little known. The aim of this research was to study the axial and radial distributions of the Sauter Mean Diameter (SMD) and velocity vectors in pulsing spray patterns of native and modified tapioca starch solutions. To meet the objective, high speed imaging and Phase Doppler Anemometry (PDA) techniques were employed to characterize the four compositions of the starch-urea-borax complex namely S0, S1, S2 and S3. The unheated solutions exhibited very high viscosities ranging from 2035 to 3030 cP. No jet breakup was seen at any stage of the nozzle operation at an injection pressure of 1-5 bar. However, at 80 °C temperature and 5 bar pressure, the viscosity was reduced to 455 to 638 cP and dense spray patterns emerged from the nozzle obscuring the PDA signals. The axial size distribution revealed a significant decrease in SMD along the spray centreline. The smallest axial SMD (51 to 79 μm) was noticed in S0 spray followed by S1, S2 and S3. Unlikely, the radial SMD in S0 spray did not vary significantly at any stage of the spray injection. This trend was attributed to the continuous growth of the surface wave instabilities on the native starch sheet. However, SMD obtained with S1, S2 and S3 varied appreciably along the radial direction. The mean velocity vector profiles followed the non-Gaussian distribution. The constant vector distributions were seen in the near nozzle regions, where the spray was in the phase of development. In far regions, the velocity vectors were poly-dispersed and a series of ups and downs were seen in the respective radial
International Nuclear Information System (INIS)
Ahmed, Mainuddin
2005-01-01
A new solution of Einstein equation in general relativity is found. This solution solves an outstanding problem of thermodynamics and black hole physics. Also this work appears to conclude the interpretation of NUT spacetime. (author)
International Nuclear Information System (INIS)
Aftanas, B.L.
1996-01-01
This Functional Design Criteria (FDC) addresses remediation of the plutonium-bearing solutions currently in inventory at the Plutonium Finishing Plant (PFP). The recommendation from the Environmental Impact Statement (EIS) is that the solutions be treated thermally and stabilized as a solid for long term storage. For solutions which are not discardable, the baseline plan is to utilize a denitration process to stabilize the solutions prior to packaging for storage
Classical solutions in supergravity
International Nuclear Information System (INIS)
Baaklini, N.S.; Ferrara, S.; Nieuwenhuizen Van, P.
1977-06-01
Classical solutions of supergravity are obtained by making finite global supersymmetry rotation on known solutions of the field equations of the bosonic sector. The Schwarzschild and the Reissner-Nordstoem solutions of general relativity are extended to various supergravity systems and the modification to the perihelion precession of planets is discussed
International Nuclear Information System (INIS)
Long, E.C.
1977-01-01
A liquid scintillation solution is described which includes (1) a scintillation solvent (toluene and xylene), (2) a primary scintillation solute (PPO and Butyl PBD), (3) a secondary scintillation solute (POPOP and Dimethyl POPOP), (4) a plurality of substantially different surfactants and (5) a filter dissolving and/or transparentizing agent. 8 claims
International Nuclear Information System (INIS)
Neace, J.C.
1986-01-01
This patent describes a process for removing diluent degradation products from a solvent extraction solution comprising an admixture of an organic extractant for uranium and plutonium and a non-polar organic liquid diluent, which has been used to recover uranium and plutonium from spent nuclear fuel. Comprising combining a wash solution consisting of: (a) water; and (b) a positive amount up to about, an including, 50 volume percent of at least one highly-polar water-miscible organic solvent, based on the total volume of the water and the highly-polar organic solvent, with the solvent extraction solution after uranium and plutonium values have been stripped from the solvent extraction solution, the diluent degradation products dissolving in the highly-polar organic solvent and the extractant and diluent of the extraction solution not dissolving in the highly-polar organic solvent, and separating the highly-polar organic solvent and the extraction solution to obtain a purified extraction solution
Proteins in solution: Fractal surfaces in solutions
Directory of Open Access Journals (Sweden)
R. Tscheliessnig
2016-02-01
Full Text Available The concept of the surface of a protein in solution, as well of the interface between protein and 'bulk solution', is introduced. The experimental technique of small angle X-ray and neutron scattering is introduced and described briefly. Molecular dynamics simulation, as an appropriate computational tool for studying the hydration shell of proteins, is also discussed. The concept of protein surfaces with fractal dimensions is elaborated. We finish by exposing an experimental (using small angle X-ray scattering and a computer simulation case study, which are meant as demonstrations of the possibilities we have at hand for investigating the delicate interfaces that connect (and divide protein molecules and the neighboring electrolyte solution.
International Nuclear Information System (INIS)
Showalter, W.E.
1984-01-01
A solution mining process which may be used for uranium, thorium, vanadium, copper, nickel, molybdenum, rhenium, and selenium is claimed. During a first injection-and-production phase of between 6 months and 5 years, a leaching solution is injected through at least one well into the formation to solubilize the mineral values and form a pregnant liquor. This liquor is recovered through another well. The leaching solution contains sulfuric acid, nitric acid, hydrochloric acid, carbonic acid, an alkali metal carbonate, an alkali metal bicarbonate, ammonium carbonate or ammonium bicarbonate. Subsequently during a first production-only phase of between about 2 weeks and one year, injection of the leaching solution is suspended but pregnant liquor is still recovered. This stage is followed by a second injection-and-production phase of between 6 months and 5 years and a second production-only phase. The mineral values are separated from the pregnant liquor to form a barren liquor. The leaching agent is introduced into this liquor, and the solution is recycled. In a second claim for the solution mining of uranium, dilute carbonic acid is used as the leaching solution. The solution has a pH less than 7 and a bicarbonate ion concentration between about 380 ppm and 1000 ppm. The injection-and-production phase lasts between one and two years and the production only phase takes between one and four months. Carbon dioxide is introduced into the barren liquor to form a dilute carbonic acid solution and the solution is recycled
El-Amin, Mohamed; Sun, Shuyu
2011-01-01
and the stability conditions are determined for each equation. Boundary layer and Boussinesq approximations have been incorporated. Numerical calculations are carried out for the various parameters entering into the problem. Velocity, temperature and concentration
Viumdal, Håkon; Mylvaganam, Saba
2017-01-01
In oil and gas and geothermal installations, open channels followed by sieves for removal of drill cuttings, are used to monitor the quality and quantity of the drilling fluids. Drilling fluid flow rate is difficult to measure due to the varying flow conditions (e.g., wavy, turbulent and irregular) and the presence of drilling cuttings and gas bubbles. Inclusion of a Venturi section in the open channel and an array of ultrasonic level sensors above it at locations in the vicinity of and above the Venturi constriction gives the varying levels of the drilling fluid in the channel. The time series of the levels from this array of ultrasonic level sensors are used to estimate the drilling fluid flow rate, which is compared with Coriolis meter measurements. Fuzzy logic, neural networks and support vector regression algorithms applied to the data from temporal and spatial ultrasonic level measurements of the drilling fluid in the open channel give estimates of its flow rate with sufficient reliability, repeatability and uncertainty, providing a novel soft sensing of an important process variable. Simulations, cross-validations and experimental results show that feedforward neural networks with the Bayesian regularization learning algorithm provide the best flow rate estimates. Finally, the benefits of using this soft sensing technique combined with Venturi constriction in open channels are discussed. PMID:29072595
Lucchesi, David M; Peron, Roberto
2010-12-03
The pericenter shift of a binary system represents a suitable observable to test for possible deviations from the newtonian inverse-square law in favor of new weak interactions between macroscopic objects. We analyzed 13 years of tracking data of the LAGEOS satellites with GEODYN II software but with no models for general relativity. From the fit of LAGEOS II pericenter residuals we have been able to obtain a 99.8% agreement with the predictions of Einstein's theory. This result may be considered as a 99.8% measurement in the field of the Earth of the combination of the γ and β parameters of general relativity, and it may be used to constrain possible deviations from the inverse-square law in favor of new weak interactions parametrized by a Yukawa-like potential with strength α and range λ. We obtained |α| ≲ 1 × 10(-11), a huge improvement at a range of about 1 Earth radius.
Energy Technology Data Exchange (ETDEWEB)
Sarman, Sten, E-mail: sarman@ownit.nu; Wang, Yong-Lei; Laaksonen, Aatto [Arrhenius Laboratory, Department of Materials and Environmental Chemistry, Stockholm University, 106 91 Stockholm (Sweden)
2016-02-07
The self-diffusion coefficients of nematic phases of various model systems consisting of regular convex calamitic and discotic ellipsoids and non-convex bodies such as bent-core molecules and soft ellipsoid strings have been obtained as functions of the shear rate in a shear flow. Then the self-diffusion coefficient is a second rank tensor with three different diagonal components and two off-diagonal components. These coefficients were found to be determined by a combination of two mechanisms, which previously have been found to govern the self-diffusion of shearing isotropic liquids, namely, (i) shear alignment enhancing the diffusion in the direction parallel to the streamlines and hindering the diffusion in the perpendicular directions and (ii) the distortion of the shell structure in the liquid whereby a molecule more readily can escape from a surrounding shell of nearest neighbors, so that the mobility increases in every direction. Thus, the diffusion parallel to the streamlines always increases with the shear rate since these mechanisms cooperate in this direction. In the perpendicular directions, these mechanisms counteract each other so that the behaviour becomes less regular. In the case of the nematic phases of the calamitic and discotic ellipsoids and of the bent core molecules, mechanism (ii) prevails so that the diffusion coefficients increase. However, the diffusion coefficients of the soft ellipsoid strings decrease in the direction of the velocity gradient because the broadsides of these molecules are oriented perpendicularly to this direction due the shear alignment (i). The cross coupling coefficient relating a gradient of tracer particles in the direction of the velocity gradient and their flow in the direction of the streamlines is negative and rather large, whereas the other coupling coefficient relating a gradient in the direction of the streamlines and a flow in the direction of the velocity gradient is very small.
Sarman, Sten; Wang, Yong-Lei; Laaksonen, Aatto
2016-02-01
The self-diffusion coefficients of nematic phases of various model systems consisting of regular convex calamitic and discotic ellipsoids and non-convex bodies such as bent-core molecules and soft ellipsoid strings have been obtained as functions of the shear rate in a shear flow. Then the self-diffusion coefficient is a second rank tensor with three different diagonal components and two off-diagonal components. These coefficients were found to be determined by a combination of two mechanisms, which previously have been found to govern the self-diffusion of shearing isotropic liquids, namely, (i) shear alignment enhancing the diffusion in the direction parallel to the streamlines and hindering the diffusion in the perpendicular directions and (ii) the distortion of the shell structure in the liquid whereby a molecule more readily can escape from a surrounding shell of nearest neighbors, so that the mobility increases in every direction. Thus, the diffusion parallel to the streamlines always increases with the shear rate since these mechanisms cooperate in this direction. In the perpendicular directions, these mechanisms counteract each other so that the behaviour becomes less regular. In the case of the nematic phases of the calamitic and discotic ellipsoids and of the bent core molecules, mechanism (ii) prevails so that the diffusion coefficients increase. However, the diffusion coefficients of the soft ellipsoid strings decrease in the direction of the velocity gradient because the broadsides of these molecules are oriented perpendicularly to this direction due the shear alignment (i). The cross coupling coefficient relating a gradient of tracer particles in the direction of the velocity gradient and their flow in the direction of the streamlines is negative and rather large, whereas the other coupling coefficient relating a gradient in the direction of the streamlines and a flow in the direction of the velocity gradient is very small.
Shcherbakov, V.; Ahlkrona, J.
2016-12-01
In this work we develop a highly efficient meshfree approach to ice sheet modeling. Traditionally mesh based methods such as finite element methods are employed to simulate glacier and ice sheet dynamics. These methods are mature and well developed. However, despite of numerous advantages these methods suffer from some drawbacks such as necessity to remesh the computational domain every time it changes its shape, which significantly complicates the implementation on moving domains, or a costly assembly procedure for nonlinear problems. We introduce a novel meshfree approach that frees us from all these issues. The approach is built upon a radial basis function (RBF) method that, thanks to its meshfree nature, allows for an efficient handling of moving margins and free ice surface. RBF methods are also accurate and easy to implement. Since the formulation is stated in strong form it allows for a substantial reduction of the computational cost associated with the linear system assembly inside the nonlinear solver. We implement a global RBF method that defines an approximation on the entire computational domain. This method exhibits high accuracy properties. However, it suffers from a disadvantage that the coefficient matrix is dense, and therefore the computational efficiency decreases. In order to overcome this issue we also implement a localized RBF method that rests upon a partition of unity approach to subdivide the domain into several smaller subdomains. The radial basis function partition of unity method (RBF-PUM) inherits high approximation characteristics form the global RBF method while resulting in a sparse system of equations, which essentially increases the computational efficiency. To demonstrate the usefulness of the RBF methods we model the velocity field of ice flow in the Haut Glacier d'Arolla. We assume that the flow is governed by the nonlinear Blatter-Pattyn equations. We test the methods for different basal conditions and for a free moving surface. Both RBF methods are compared with a classical finite element method in terms of accuracy and efficiency. We find that the RBF methods are more efficient than the finite element method and well suited for ice dynamics modeling, especially the partition of unity approach.
Yuan, S. W. K.
1985-01-01
This investigation of vapor-liquid phase separation (VLPS) of He 2 is related to long-term storage of cryogenic liquid. The VLPS system utilizes porous plugs in order to generate thermomechanical (thermo-osmotic) force which in turn prevents liquid from flowing out of the cryo-vessel (e.g., Infrared Astronomical Satellite). An apparatus was built and VLPS data were collected for a 2 and a 10 micrometer sintered stainless steel plug and a 5 to 15 micrometer sintered bronze plug. The VLPS data obtained at high temperature were in the nonlinear turbulent regime. At low temperature, the Stokes regime was approached. A turbulent flow model was developed, which provides a phenomenological description of the VLPS data. According to the model, most of the phase separation data are in the turbulent regime. The model is based on concepts of the Gorter-Mellink transport involving the mutual friction known from the zero net mass flow (ZNMF) studies. The latter had to be modified to obtain agreement with the present experimental VLPS evidence. In contrast to the well-known ZNMF mode, the VLPS results require a geometry dependent constant (Gorter-Mellink constant). A theoretical interpretation of the phenomenological equation for the VLPS data obtained, is based on modelling of the dynamics of quantized vortices proposed by Vinen. In extending Vinen's model to the VLPS transport of He 2 in porous media, a correlation between the K*(GM) and K(p) was obtained which permits an interpretation of the present findings. As K(p) is crucial, various methods were introduced to measure the permeability of the porous media at low temperatures. Good agreement was found between the room temperature and the low temperature K(p)-value of the plugs.
Tanaka, H.; Shiomi, Y.; Ma, K.-F.
2017-11-01
To understand the fault zone fluid flow-like structure, namely the ductile deformation structure, often observed in the geological field (e.g., Ramsay and Huber The techniques of modern structure geology, vol. 1: strain analysis, Academia Press, London, 1983; Hobbs and Ord Structure geology: the mechanics of deforming metamorphic rocks, Vol. I: principles, Elsevier, Amsterdam, 2015), we applied a theoretical approach to estimate the rate of deformation, the shear stress and the time to form a streak-line pattern in the boundary layer of viscous fluids. We model the dynamics of streak lines in laminar boundary layers for Newtonian and pseudoplastic fluids and compare the results to those obtained via laboratory experiments. The structure of deformed streak lines obtained using our model is consistent with experimental observations, indicating that our model is appropriate for understanding the shear rate, flow time and shear stress based on the profile of deformed streak lines in the boundary layer in Newtonian and pseudoplastic viscous materials. This study improves our understanding of the transportation processes in fluids and of the transformation processes in fluid-like materials. Further application of this model could facilitate understanding the shear stress and time history of the fluid flow-like structure of fault zones observed in the field.[Figure not available: see fulltext.
International Nuclear Information System (INIS)
Long, E.C.
1976-01-01
The invention deals with a liquid scintillation solution which contains 1) a scintillation solvent (toluol), 2) a primary scintillation solute (PPO), 3) a secondary scintillation solute (dimethyl POPOP), 4) several surfactants (iso-octyl-phenol polyethoxy-ethanol and sodium di-hexyl sulfosuccinate) essentially different from one another and 5) a filter resolution and/or transparent-making agent (cyclic ether, especially tetrahydrofuran). (HP) [de
Highly Branched Polyisobutylene by Radical Polymerization under Li[CB11(CH3)(12)] Catalysis
Czech Academy of Sciences Publication Activity Database
Volkis, V.; Shoemaker, R. K.; Michl, Josef
2012-01-01
Roč. 45, č. 23 (2012), s. 9250-9257 ISSN 0024-9297 Institutional research plan: CEZ:AV0Z40550506 Keywords : Dodecamethylcarba-closo-dodecaborate(-)Anion * polymerization * LiCB11(CH3)(12) Subject RIV: CC - Organic Chemistry Impact factor: 5.521, year: 2012
PERVASIVE BUSINESS INTELLIGENCE SOLUTIONS
Directory of Open Access Journals (Sweden)
Rocsana Tonis (Bucea-Manea
2011-03-01
Full Text Available The utility of BI solutions is accepted all over the world in the modern organizations. However, the BI solutions do not offer a constant feedback in line with the organizational activities. In this context, there have been developed pervasive BI solutions which are present at different levels of the organization, so that employees can observe only what is most relevant to their day-to-day tasks. They are organized in vertical silos, with clearly identified performance and expectations. The paper emphasizes the role of pervasive BI solutions in reaching the key performance indicators of the modern organizations, more important in the context of crisis.
Solute-solute interactions in intermetallic compounds
Energy Technology Data Exchange (ETDEWEB)
Banerjee, Debashis; Murray, Ryan; Collins, Gary S., E-mail: collins@wsu.edu [Washington State University, Department of Physics and Astronomy (United States); Zacate, Matthew O. [Northern Kentucky University, Department of Physics and Geology (United States)
2017-11-15
Experiments were carried out on highly ordered GdAl{sub 2} samples containing extremely dilute mole fractions of{sup 111}In/Cd probe-atom solutes (about 10{sup −11}), intrinsic antisite atoms Al{sub Gd} having mole fractions of order 0-10{sup −2}, and doped with Ag solutes at mole fractions of order 10{sup −2}. Three types of defect interactions were investigated. (1) Quadrupole interactions caused by Ag-solute atoms neighboring{sup 111}In/Cd solute probe atoms were detected using the method of perturbed angular correlation of gamma rays (PAC). Three complexes of pairs of In-probes and Ag-solutes occupying neighboring positions on Gd- and Al-sublattices were identified by comparing site fractions in Gd-poor and Gd-rich GdAl{sub 2}(Ag) samples and from the symmetry of the quadrupole interactions. Interaction enthalpies between solute-atom pairs were determined from temperature dependences of observed site fractions. Repulsive interactions were observed for close-neighbor complexes In{sub Gd}+Ag{sub Gd} and In{sub Gd}+Ag{sub Al} pairs, whereas a slightly attractive interaction was observed for In{sub Al}+Ag{sub Al}. Interaction enthalpies were all small, in the range ±0.15 eV. (2) Quadrupole interactions caused by intrinsic antisite atoms Al{sub Gd} neighboring In{sub Gd} probes were also detected and site fractions measured as a function of temperature, as in previous work on samples not doped with Ag-solutes [Temperature- and composition-driven changes in site occupation of solutes in Gd{sub 1+3x}Al{sub 2−3x}, Zacate and Collins (Phys. Rev. B69, 174202 (1))]. However, the effective binding enthalpy between In{sub Gd} probe and Al{sub Gd} antisite was found to change sign from -0.12 eV (attractive interaction) in undoped samples to + 0.24 eV (repulsive) in Ag-doped samples. This may be attributed to an attractive interaction between Al{sub Gd} antisite atoms and Ag-dopants that competes with the attractive interaction between In{sub Gd} and Al{sub Gd
International Nuclear Information System (INIS)
Balantekin, A. B.; Pehlivan, Y.
2007-01-01
We give the exact solution of orbit dependent nuclear pairing problem between two nondegenerate energy levels using the Bethe ansatz technique. Our solution reduces to previously solved cases in the appropriate limits including Richardson's treatment of reduced pairing in terms of rational Gaudin algebra operators
Dadhich, Naresh
2010-01-01
We show that the asymptotic large $r$ limit of all Lovelock vacuum and electrovac solutions with $\\Lambda$ is always the Einstein solution in $d \\geq 2n+1$ dimensions. It is completely free of the order $n$ of the Lovelock polynomial indicating universal asymptotic behaviour.
Rational Solutions and Lump Solutions of the Potential YTSF Equation
Sun, Hong-Qian; Chen, Ai-Hua
2017-07-01
By using of the bilinear form, rational solutions and lump solutions of the potential Yu-Toda-Sasa-Fukuyama (YTSF) equation are derived. Dynamics of the fundamental lump solution, n1-order lump solutions, and N-lump solutions are studied for some special cases. We also find some interaction behaviours of solitary waves and one lump of rational solutions.
Energy Technology Data Exchange (ETDEWEB)
Bena, Iosif [Institut de Physique Théorique, Université Paris Saclay, CEA, CNRS, 91191 Gif-sur-Yvette Cedex (France); Bossard, Guillaume [Centre de Physique Théorique, Ecole Polytechnique, CNRS, Université Paris-Saclay, 91128 Palaiseau Cedex (France); Katmadas, Stefanos; Turton, David [Institut de Physique Théorique, Université Paris Saclay, CEA, CNRS, 91191 Gif-sur-Yvette Cedex (France)
2017-01-30
We introduce a solvable system of equations that describes non-extremal multicenter solutions to six-dimensional ungauged supergravity coupled to tensor multiplets. The system involves a set of functions on a three-dimensional base metric. We obtain a family of non-extremal axisymmetric solutions that generalize the known multicenter extremal solutions, using a particular base metric that introduces a bolt. We analyze the conditions for regularity, and in doing so we show that this family does not include solutions that contain an extremal black hole and a smooth bolt. We determine the constraints that are necessary to obtain smooth horizonless solutions involving a bolt and an arbitrary number of Gibbons-Hawking centers.
International Nuclear Information System (INIS)
Dzhunushaliev, Vladimir; Minamitsuji, Masato; Folomeev, Vladimir
2010-01-01
This paper gives a comprehensive review on thick brane solutions and related topics. Such models have attracted much attention from many aspects since the birth of the brane world scenario. In many works, it has been usually assumed that a brane is an infinitely thin object; however, in more general situations, one can no longer assume this. It is also widely considered that more fundamental theories such as string theory would have a minimal length scale. Many multidimensional field theories coupled to gravitation have exact solutions of gravitating topological defects, which can represent our brane world. The inclusion of brane thickness can realize a variety of possible brane world models. Given our understanding, the known solutions can be classified into topologically non-trivial solutions and trivial ones. The former class contains solutions of a single scalar (domain walls), multi-scalar, gauge-Higgs (vortices), Weyl gravity and so on. As an example of the latter class, we consider solutions of two interacting scalar fields. Approaches to obtain cosmological equations in the thick brane world are reviewed. Solutions with spatially extended branes (S-branes) and those with an extra time-like direction are also discussed.
Lublinsky, Boris; Yakubovich, Alexey
2013-01-01
The go-to guidebook for deploying Big Data solutions with Hadoop Today's enterprise architects need to understand how the Hadoop frameworks and APIs fit together, and how they can be integrated to deliver real-world solutions. This book is a practical, detailed guide to building and implementing those solutions, with code-level instruction in the popular Wrox tradition. It covers storing data with HDFS and Hbase, processing data with MapReduce, and automating data processing with Oozie. Hadoop security, running Hadoop with Amazon Web Services, best practices, and automating Hadoop processes i
Directory of Open Access Journals (Sweden)
TUTUNEA MIHAELA FILOFTEIA
2012-09-01
Full Text Available The integration of activities, the business processes as well as their optimization, bring the perspective of profitable growth and create significant and competitive advantages in any company. The adoption of some ERP integrated software solutions, from SMEs’ perspective, must be considered as a very important management decision in medium and long term. ERP solutions, along with the transparent and optimized management of all internal processes, also offer an intra and inter companies collaborative platform, which allows a rapid expansion of activities towards e- business and mobile-business environments. This material introduces ERP solutions for SMEs from commercial offer and open source perspective; the results of comparative analysis of the solutions on the specific market, can be an useful aid to the management of the companies, in making the decision to integrate business processes, using ERP as a support.
Technical product bulletin: aka OIL SOLUTIONS POWDER, SPILL GREEN LS, this miscellaneous oil spill control agent used in cleanups initially behaves like a synthetic sorbent, then as a solidifier as the molecular microencapsulating process occurs.
Adair, Aaron Michael
experience of force; students claim to feel a force in the direction of relative motion even when the actual force is in the opposite direction. The interview process also showed how students had both their intuitive sense of physics as well as Newtonian concepts from instruction, and how each model was activated could be influenced by questions from the interviewer. In order to investigate how changes to instructional method and pedagogy may affect students' ability to overcome their non-Newtonian intuitions, an experimental lecturing series was devised that used individual voting machines ("clickers") to increase class participation and dialog in a fashion that was more student-centered. The experimental section also had video recordings of the lectures as well as concept-based video homework solutions. The initial availability of the videos hindered early use, and overall students rarely used these additions. The clicker system also had technical issues due to the volume of students and an interface that was not streamlined. Nonetheless, the results showed the experimental section to have significantly greater learning gains (d > 0.5, p ˜ 0.01), and we determined that this was most likely due to the clicker system.
Conductometry of electrolyte solutions
Safonova, Lyubov P.; Kolker, Arkadii M.
1992-09-01
A review is given of the theories of the electrical conductance of electrolyte solutions of different ionic strengths and concentrations, and of the models of ion association. An analysis is made of the methods for mathematical processing of experimental conductometric data. An account is provided of various theories describing the dependence of the limiting value of the ionic electrical conductance on the properties of the solute and solvent. The bibliography includes 115 references.
Lü, H; Mei, Jianwei; Pope, C N
2009-08-28
Recently Horava proposed a nonrelativistic renormalizable theory of gravitation, which reduces to Einstein's general relativity at large distances, and that may provide a candidate for a UV completion of Einstein's theory. In this Letter, we derive the full set of equations of motion, and then we obtain spherically symmetric solutions and discuss their properties. We also obtain solutions for the Friedmann-Lemaître-Robertson-Walker cosmological metric.
Piezoelectric Energy Harvesting Solutions
Caliò, Renato; Rongala, Udaya Bhaskar; Camboni, Domenico; Milazzo, Mario; Stefanini, Cesare; de Petris, Gianluca; Oddo, Calogero Maria
2014-01-01
This paper reviews the state of the art in piezoelectric energy harvesting. It presents the basics of piezoelectricity and discusses materials choice. The work places emphasis on material operating modes and device configurations, from resonant to non-resonant devices and also to rotational solutions. The reviewed literature is compared based on power density and bandwidth. Lastly, the question of power conversion is addressed by reviewing various circuit solutions. PMID:24618725
International Nuclear Information System (INIS)
Habersbergerova, A.; Janovsky, I.
1985-01-01
The factors were studied affecting thiosulfate radiolysis in the so-called spray solution for nuclear power plant containments. The reaction mechanism of primary radiolytic reactions leading to thiosulfate decomposition was studied using pulse radiolysis. Also measured was hydrazine loss in the irradiation of the bubbling solution intended for the capture of volatile chemical forms of radioiodine. Pulse radiolysis was used to study the kinetics of hydrazine reaction with elemental iodine. (author)
Energy Technology Data Exchange (ETDEWEB)
Radiuk, M I; Iushkova, N E; Kozubovskii, A I
1979-10-25
A boring solution is being patented for boring for oil and gas, which can be used in wells, where the temperature of the circulating liquid reaches 100/sup 0/. Polyvinyl acetate emulsion (PVE) is added for the purpose of decreasing viscosity of the solution at a temperature of agression into the boring solution containing clay, water, carboxymethylcellulose (CBC), a chloride from the number of sodium, potassium, or magnesium chlorides. The solution has the following composition in %: clay, 10 to 20; CBC, 1.5 to 2.0; chloride, 5 to 20; PVE, 0.5 to 2; water, up to 100. In accordance to GOST 1000-62 for the accepted PVE, the compound has the following composition, in %: monomer, 0.8; dry residue, greater than or equal to 50; plasticizer (tributyl phthalate), 5 to 15. The boring solution is processed according to the following method. The original solution, containing clay, water, salts, receives 1.5 to 2% CBC and afterwards it is processed with 0.5 to 2% PVE.
Social information solution; Shakai joho solution
Energy Technology Data Exchange (ETDEWEB)
NONE
2000-01-10
An information system for government offices is developed, a system that integrally supports operations inside government offices and the staff service operations by combining Intra Net as the basis of an information system with Internet. The objective of the system is as follows: (1) Information sharing in the place of work and utilization of information resources. (2) Improvement in administrative services and vitalization of an interchange of residents through the preparation of Internet environment. (3) Rationalization of staff operations through groupeware. In addition, by building a network system for the entire region, information communication service is to be provided as a solution between the residents and the administration in the occurrence of a disaster as well as for home care, medical and nursing assistance in the health, medical and welfare fields. (translated by NEDO)
Energy Technology Data Exchange (ETDEWEB)
Strom, I.; Joosten, L.; Boonstra, C. [DHV Sustainability Consultants, Eindhoiven (Netherlands)
2006-05-15
PEP stands for 'Promotion of European Passive Houses' and is a consortium of European partners, supported by the European Commission, Directorate General for Energy and Transport. In this working paper an overview is given of Passive House solutions. An inventory has been made of Passive House solutions for new build residences applied in each country. Based on this, the most common basic solutions have been identified and described in further detail, including the extent to which solutions are applied in common and best practice and expected barriers for the implementation in each country. An inventory per country is included in the appendix. The analysis of Passive House solutions in partner countries shows high priority with regard to the performance of the thermal envelope, such as high insulation of walls, roofs, floors and windows/ doors, thermal bridge-free construction and air tightness. Due to the required air tightness, special attention must be paid to indoor air quality through proper ventilation. Finally, efficient ((semi-)solar) heating systems for combined space and DHW heating still require a significant amount of attention in most partner countries. Other basic Passive House solutions show a smaller discrepancy with common practice and fewer barriers have been encountered in partner countries. In the next section, the general barriers in partner countries have been inventoried. For each type of barrier a suggested approach has been given. Most frequently encountered barriers in partner countries are: limited know-how; limited contractor skills; and acceptation of Passive Houses in the market. Based on the suggested approaches to overcoming barriers, this means that a great deal of attention must be paid to providing practical information and solutions to building professionals, providing practical training to installers and contractors and communication about the Passive House concept to the market.
Siemens IT solutions for power sector. PROFIT solutions
International Nuclear Information System (INIS)
Lunter, P.
2004-01-01
The cost reduction, flexibility and revenue increase, potential exploitation, productivity increase, and business opportunities exploitation - that is all what can be required in the races for the promonent positioning on the electricity power market. These requirements can be realized by the sophisticated IT solutions hand-tailored to the special requirements of the electric power producers and tradesmen. This approach makes it possible to achieve greater profit. Our solutions 'PROFIT Solutions', that are symbiosis of the most progressive information technologies and the power plant techniques of the company Siemens, satisfy submitted specifications in substantial measure. The system solutions 'PROFIT Solutions' comprise three solution groups: process, operation a business. The solutions of the group 'IT Process Solutions' increase flexibility and manoeuvrability of equipment, improve the efficiency and contribute to more economical operation of the power generation. Solutions 'IT Process Solutions' simplify and shorten the period of power cycles and conduce to higher labour productivity. Solutions group 'IT Process Solutions' approaches equipment to the market - supports the profit strategies, helps quickly and expertly to determine and predict hazards. The extension PROFIT Cockpit means the nuance to the solutions world 'PROFIT Solutions'. The survey about the whole installation is within reach at the simple touch of a button. It is possible to compile the total system part by part from single solutions 'PROFIT Solutions'. As a matter of fact all single parts can be interconnected with already existing solutions. Routines 'PROFIT Solutions' cooperate with all modern control systems. (author)
Solute segregation during irradiation
International Nuclear Information System (INIS)
Wiedersich, H.; Okamoto, P.R.; Lam, N.Q.
1977-01-01
Irradiation at elevated temperature induces redistribution of the elements in alloys on a microstructural level. This phenomenon is caused by differences in the coupling of the various alloy constituents to the radiation-induced defect fluxes. A simple model of the segregation process based on coupled reaction-rate and diffusion equations is discussed. The model gives a good description of the experimentally observed consequences of radiation-induced segregation, including enrichment or depletion of solute elements near defect sinks such as surfaces, voids and dislocations; precipitation of second phases in solid solutions; precipitate redistribution in two-phase alloys; and effects of defect-production rates on void-swelling rates in alloys with minor solute additions
Superstrings fermionic solutions
International Nuclear Information System (INIS)
Rausch de Traubenberg, M.
1990-06-01
The solutions proposed by the superstring theory are classified and compared. In order to obtain some of the equivalences, the demonstration is based on the coincidence of the excitation spectrum and the quantum numbers from different states. The fermionic representation of the heterotical strings is discussed. The conformal invariance and the supersymmetric results extended to two dimensions are investigated. Concerning the fermionic strings, the formalism and a phenomenological solution involving three families of quarks, chiral leptons and leptons from the E 6 gauge group are presented. The equivalence between real and complex fermions is discussed. The similarity between some of the solutions of the Wess-Zumino-Witten model and the orbifolds is considered. The formal calculation program developed for reproducing the theory's low energy spectra, in the fermionic string formalism is given [fr
Decontamination solution development studies
International Nuclear Information System (INIS)
Allen, R.P.; Fetrow, L.K.; Kjarmo, H.E.; Pool, K.H.
1993-09-01
This study was conducted for the Westinghouse Hanford Company (WHC) by Pacific Northwest Laboratory (PNL) as part of the Hanford Grout Technology Program (HGTP). The objective of this study was to identify decontamination solutions capable of removing radioactive contaminants and grout from the Grout Treatment Facility (GTF) process equipment and to determine the impact of these solutions on equipment components and disposal options. The reference grout used in this study was prepared with simulated double-shell slurry feed (DSSF) and a dry blend consisting of 40 wt % limestone flour, 28 wt % blast furnace slag, 28 wt % fly ash, and 4 wt % type I/II Portland cement
Calculus problems and solutions
Ginzburg, Abraham
2011-01-01
Ideal for self-instruction as well as for classroom use, this text helps students improve their understanding and problem-solving skills in analysis, analytic geometry, and higher algebra. More than 1,200 problems appear in the text, with concise explanations of the basic notions and theorems to be used in their solution. Many are followed by complete answers; solutions for the others appear at the end of the book. Topics include sequences, functions of a single variable, limit of a function, differential calculus for functions of a single variable, fundamental theorems and applications of dif
DEFF Research Database (Denmark)
Ørding Olsen, Anders
when pursuing minor performance improvements in existing technologies. However, reliance on internal knowledge sources carries a risk of organizational inertia related to problem understanding and solution development in the shape of path-dependencies and preferences for exploitation and reapplication...... of existing knowledge. Such inertia may imbue innovation processes related to the development of new technologies with reduced novelty and an inability to recognize alternative and potentially more attractive solutions. As a result, over-reliance on internal knowledge sources is likely to inhibit the ability...
Business Intelligence Integrated Solutions
Directory of Open Access Journals (Sweden)
Cristescu Marian Pompiliu
2017-12-01
Full Text Available A Business Intelligence solution concerns the simple, real-time access to complete information about the business shown in a relevant format of the report, graphic or dashboard type in order help the taking of strategic decisions regarding the direction in which the company goes. Business Intelligence does not produce data, but uses the data produced by the company’s applications. BI solutions extract their data from ERP (Enterprise Resource Planning, CRM (Customer Relationship Management, HCM (Human Capital Management, and Retail, eCommerce or other databases used in the company.
Jorgensen, Adam; Welch, John; Clark, Dan; Price, Christopher; Mitchell, Brian
2014-01-01
Tap the power of Big Data with Microsoft technologies Big Data is here, and Microsoft's new Big Data platform is a valuable tool to help your company get the very most out of it. This timely book shows you how to use HDInsight along with HortonWorks Data Platform for Windows to store, manage, analyze, and share Big Data throughout the enterprise. Focusing primarily on Microsoft and HortonWorks technologies but also covering open source tools, Microsoft Big Data Solutions explains best practices, covers on-premises and cloud-based solutions, and features valuable case studies. Best of all,
Phenomenology of polymer solution dynamics
National Research Council Canada - National Science Library
Phillies, George D. J
2011-01-01
... solutions, not dilute solutions or polymer melts. From centrifugation and solvent dynamics to viscosity and diffusion, experimental measurements and their quantitative representations are the core of the discussion...
Aliteracy : causes and solutions
Nielen, Thijs Martinus Johannes
2016-01-01
The reading motivation of the majority of students declines in the upper half of primary school, which implies a risk for aliteracy: Students can read but, due to lack of practice, their skills remain underdeveloped (Chapter 2). In this thesis we have explored causes and solutions for this important
Zee, van der S.E.A.T.M.; Leijnse, A.
2013-01-01
Solute transport is of importance in view of the movement of nutrient elements, e.g. towards the plant root system, and because of a broad range of pollutants. Pollution is not necessarily man induced, but may be due to geological or geohydrological causes, e.g. in the cases of pollution with
An Inexpensive Solution Calorimeter
Kavanagh, Emma; Mindel, Sam; Robertson, Giles; Hughes, D. E. Peter
2008-01-01
We describe the construction of a simple solution calorimeter, using a miniature bead thermistor as a temperature-sensing element. This has a response time of a few seconds and made it possible to carry out a thermometric reaction in under a minute, which led to minimal heat losses. Small temperature changes of 1 K associated with enthalpies of…
Aqueous polyethylene oxide solutions
International Nuclear Information System (INIS)
Breen, J.
1987-01-01
A number of aspects concerning the reorientation of polymer, water and ion hydration complexes have been studied in aqueous solution of polyethylene oxide (PEO). The polymer dynamics are investigated by 1 H-PEO and 13 C-PEO nuclear relaxation experiments. 162 refs.; 30 figs.; 19 tabs
Weak solutions of magma equations
International Nuclear Information System (INIS)
Krishnan, E.V.
1999-01-01
Periodic solutions in terms of Jacobian cosine elliptic functions have been obtained for a set of values of two physical parameters for the magma equation which do not reduce to solitary-wave solutions. It was also obtained solitary-wave solutions for another set of these parameters as an infinite period limit of periodic solutions in terms of Weierstrass and Jacobian elliptic functions
Earnest Rutherford, the solution
2003-01-01
If you did not make it to the Science & Society talk by John Campbell last week and are still wondering about the spelling of "Earnest", here is the solution: Two months after the birth of his fourth child on 30 August 1871 in Spring Grove, New Zealand, James Rutherford registered his son, who was recorded as "Earnest" in the Birth Register. Presumably the Registrar wrote the name down as it sounded and the father failed to notice the mistake when signing the Register.
Molybdenum from uranium solutions
International Nuclear Information System (INIS)
Gardner, H.E.
1981-01-01
A method of removing molybdenum from a uranium bearing solution is claimed. It comprises adding sufficient reactive lead compound to supply at least 90 percent of the stoichiometric quantity of lead ion required to fully react with the molybdenum present to form insoluble lead molybdate and continuing the reaction with agitation until the desired percentage of the molybdenum present has reacted with the lead ion
Severe service sealing solutions
International Nuclear Information System (INIS)
Metcalfe, R.; Wensel, R.
1994-09-01
Successful sealing usually requires much more than initial leak-tightness. Friction and wear must also be acceptable, requiring a good understanding of tribology at the sealing interface. This paper describes various sealing solutions for severe service conditions. The CAN2A and CAN8 rotary face seals use tungsten carbide against carbon-graphite to achieve low leakage and long lifetime in nuclear main coolant pumps. The smaller CAN6 seal successfully uses tungsten carbide against silicon carbide in reactor water cleanup pump service. Where friction in CANDU fuelling machine rams must be essentially zero, a hydrostatic seal using two silicon carbide faces is the solution. In the NRU reactor moderator pumps, where pressure is much lower, eccentric seals that prevent boiling at the seal faces are giving excellent service. All these rotary face seals rely on supplementary elastomer seals between their parts. An integrated engineering approach to high performance sealing with O-rings is described. This is epitomized in critical Space Shuttle applications, but is increasingly being applied in CANDU plants. It includes gland design, selection and qualification of material, quality assurance, detection of defects and the effects of lubrication, surface finish, squeeze, stretch and volume constraints. In conclusion, for the severe service applications described, customized solutions have more than paid for themselves by higher reliability, lower maintenance requirements and reduced outage time. (author)
International Nuclear Information System (INIS)
Hunkin, G.G.
1980-01-01
The field of application of in-situ solution mining of uranium is described and areas of competition with open pit and underground mining identified. The influence of high interest rates and dollar inflation on present values and rate of return is shown to be minimized by low capitalization and short construction lead times typical of in-situ leaching ventures. A scheme of three major project account divisions is presented and basic parameters necessary for mine planning are listed. 1979 cost ranges and useful methods of estimation of capital and operating costs are given for the in-situ uranium mining method
Total Logistic Plant Solutions
Directory of Open Access Journals (Sweden)
Dusan Dorcak
2016-02-01
Full Text Available The Total Logistics Plant Solutions, plant logistics system - TLPS, based on the philosophy of advanced control processes enables complex coordination of business processes and flows and the management and scheduling of production in the appropriate production plans and planning periods. Main attributes of TLPS is to create a comprehensive, multi-level, enterprise logistics information system, with a certain degree of intelligence, which accepts the latest science and research results in the field of production technology and logistics. Logistic model of company understands as a system of mutually transforming flows of materials, energy, information, finance, which is realized by chain activities and operations
DEFF Research Database (Denmark)
Chakkol, Mehmet; Johnson, Mark; Raja, Jawwad
2014-01-01
Purpose – This paper aims to adopt service-dominant logic (SDL) to empirically explore network configurations resulting from the provision of goods, goods and services, and solutions. Design/methodology/approach – This paper uses a single, in-depth, exploratory case study in a truck manufacturer......: dyadic, triadic and tetradic. The extent to which different network actors contribute to value co-creation varies across the offerings. Research limitations/implications – This paper is based on a single, in-depth case study developed in one industrial context. Whilst this represents an appropriate...
Energy Technology Data Exchange (ETDEWEB)
Gen, O P; Azhigaliyev, G K; Dodonova, S Ye; Dyaltlova, N M; Novokhatskaya, I D; Ryabova, L I
1984-01-01
The purpose of the invention is to increase the durability of cement stone at 150 to 200C. The patent covers a plugging solution which consists of Portlandcement, sand and water. It additionally contains metal organic complexes of nitrylotrimethylphosphonic acid and organosiliconates of alkali or alkaline earth metals with the following component relationship in percent by mass: Portland cement, 42 to 43; sand, 27 to 28; metal organic complexes of nitrylotrimethylphosphonic acid, 0.01 to 1.5; organosiliconates of alkaline or alkaline earthmetals, 0.0025 to 0.375 and water, the remainder.
POWER-LAW AKIŞKANI İLE YAĞLANMIŞ EKSENEL KAYMALI YATAKTA BASINÇ VE HIZ DAĞILIMI
Directory of Open Access Journals (Sweden)
Muhammet YÜRÜSOY
2000-02-01
Full Text Available In this study, a slider bearing lubricated with a non-Newtonian fluid namely a Power-Law fluid is considered. First the equations of motion are derived. Perturbation methods are employed in search of approximate solutions. The simplest perturbation expansion, namely the pedestrian expansion, is used. The velocity distribution and the pressure distribution are calculated approximately. The solutions are expressed in dimensionless form for convenience. The variation of pressure and velocity with the non-Newtonian behaviour and bearing dimensions are plotted.
Classical solutions and extended supergravity
International Nuclear Information System (INIS)
de Alfaro, V.; Fubini, S.; Furlan, G.
1980-03-01
The existence and properties of classical solutions for gravity coupled to matter fields have been investigated previously with the limitation to conformally flat solutions. In the search for a guiding criterion to determine the form of the coupling among the fields, one is led to consider supersymmetric theories, and the question arises whether classical solutions persist in these models. It is found that a discrepancy persists between supergravity and standard meron solutions. Owing to the appearance of the scalar field, a new set of meron solutions exists for particular Lagrangian models. In conclusion, the form of solutions in Minkowski space is discussed
Radioactive waste management solutions
International Nuclear Information System (INIS)
Siemann, Michael
2015-01-01
One of the more frequent questions that arise when discussing nuclear energy's potential contribution to mitigating climate change concerns that of how to manage radioactive waste. Radioactive waste is produced through nuclear power generation, but also - although to a significantly lesser extent - in a variety of other sectors including medicine, agriculture, research, industry and education. The amount, type and physical form of radioactive waste varies considerably. Some forms of radioactive waste, for example, need only be stored for a relatively short period while their radioactivity naturally decays to safe levels. Others remain radioactive for hundreds or even hundreds of thousands of years. Public concerns surrounding radioactive waste are largely related to long-lived high-level radioactive waste. Countries around the world with existing nuclear programmes are developing longer-term plans for final disposal of such waste, with an international consensus developing that the geological disposal of high-level waste (HLW) is the most technically feasible and safe solution. This article provides a brief overview of the different forms of radioactive waste, examines storage and disposal solutions, and briefly explores fuel recycling and stakeholder involvement in radioactive waste management decision making
2001-01-01
REI Systems, Inc. developed a software solution that uses the Internet to eliminate the paperwork typically required to document and manage complex business processes. The data management solution, called Electronic Handbooks (EHBs), is presently used for the entire SBIR program processes at NASA. The EHB-based system is ideal for programs and projects whose users are geographically distributed and are involved in complex management processes and procedures. EHBs provide flexible access control and increased communications while maintaining security for systems of all sizes. Through Internet Protocol- based access, user authentication and user-based access restrictions, role-based access control, and encryption/decryption, EHBs provide the level of security required for confidential data transfer. EHBs contain electronic forms and menus, which can be used in real time to execute the described processes. EHBs use standard word processors that generate ASCII HTML code to set up electronic forms that are viewed within a web browser. EHBs require no end-user software distribution, significantly reducing operating costs. Each interactive handbook simulates a hard-copy version containing chapters with descriptions of participants' roles in the online process.
Capillary thinning of polymeric filaments
DEFF Research Database (Denmark)
Kolte, Mette Irene; Szabo, Peter
1999-01-01
The capillary thinning of filaments of a Newtonian polybutene fluid and a viscoelastic polyisobutylene solution are analyzed experimentally and by means of numerical simulation. The experimental procedure is as follows. Initially, a liquid sample is placed between two cylindrical plates. Then, th...
International Nuclear Information System (INIS)
Boersma, M.
2001-01-01
The need to consider the Middle East as a group of distinct countries and not as one single market and to tailor the services offered by companies is stressed. The cultures, political and social conditions, forms of the oil and gas industry in the countries making up the Middle East and their technology requirements are different and vary widely. The approach taken by Shell Global Solutions to these differences is described and illustrated with Shell's experiences in Oman and Saudi Arabia. Shell has found that Omanis are keen to work in their oil and gas industry, and to protect their country's natural environment. Saudi also have intense pride in their oil industry and here Shell supports refinery operators reduce costs while maintaining strict quality control. Shell has been selected to help Saudi Arabia develop its natural gas reserves; as part of the Core Venture 3 project, Shell will build a power desalination plant
International Nuclear Information System (INIS)
Urbanczyk, A.; Kalinowski, M.K.
1983-01-01
The electronic absorption spectrum of vanadyl acetylacetonate has been studied in 15 organic solvents. It has been found that wavenumbers and molar absorptivities of the long-wavelength bands (d-d transitions) can be well described by a complementary Lewis acid-base model including Gutmann's donor number [Gutmann V., Wychera E., Inorg. Nucl. Chem. Letters 2, 257 (1966)] and acceptor number [Mayer U., Gutmann V., Gerger W., Monatsh. Chem. 106, 1235 (1975)] of a solvent. This model describes also the solvent effect of the hyperfine splitting constant, Asub(iso)( 51 V), from e.s.r. spectra of VOacac 2 . These observations are discussed in terms of the donor-acceptor concept for solvent-solute interactions. (Author)
2010 Water & Aqueous Solutions
Energy Technology Data Exchange (ETDEWEB)
Dor Ben-Amotz
2010-08-13
Water covers more than two thirds of the surface of the Earth and about the same fraction of water forms the total mass of a human body. Since the early days of our civilization water has also been in the focus of technological developments, starting from converting it to wine to more modern achievements. The meeting will focus on recent advances in experimental, theoretical, and computational understanding of the behavior of the most important and fascinating liquid in a variety of situations and applications. The emphasis will be less on water properties per se than on water as a medium in which fundamental dynamic and reactive processes take place. In the following sessions, speakers will discuss the latest breakthroughs in unraveling these processes at the molecular level: Water in Solutions; Water in Motion I and II; Water in Biology I and II; Water in the Environment I and II; Water in Confined Geometries and Water in Discussion (keynote lecture and poster winners presentations).
Diffusion of aqueous solutions of ionic, zwitterionic, and polar solutes
Teng, Xiaojing; Huang, Qi; Dharmawardhana, Chamila Chathuranga; Ichiye, Toshiko
2018-06-01
The properties of aqueous solutions of ionic, zwitterionic, and polar solutes are of interest to many fields. For instance, one of the many anomalous properties of aqueous solutions is the behavior of water diffusion in different monovalent salt solutions. In addition, solutes can affect the stabilities of macromolecules such as proteins in aqueous solution. Here, the diffusivities of aqueous solutions of sodium chloride, potassium chloride, tri-methylamine oxide (TMAO), urea, and TMAO-urea are examined in molecular dynamics simulations. The decrease in the diffusivity of water with the concentration of simple ions and urea can be described by a simple model in which the water molecules hydrogen bonded to the solutes are considered to diffuse at the same rate as the solutes, while the remainder of the water molecules are considered to be bulk and diffuse at almost the same rate as pure water. On the other hand, the decrease in the diffusivity of water with the concentration of TMAO is apparently affected by a decrease in the diffusion rate of the bulk water molecules in addition to the decrease due to the water molecules hydrogen bonded to TMAO. In other words, TMAO enhances the viscosity of water, while urea barely affects it. Overall, this separation of water molecules into those that are hydrogen bonded to solute and those that are bulk can provide a useful means of understanding the short- and long-range effects of solutes on water.
Griscom, Bronson W.; Adams, Justin; Ellis, Peter W.; Houghton, Richard A.; Lomax, Guy; Miteva, Daniela A.; Schlesinger, William H.; Shoch, David; Siikamäki, Juha V.; Smith, Pete; Woodbury, Peter; Zganjar, Chris; Blackman, Allen; Campari, João; Conant, Richard T.; Delgado, Christopher; Elias, Patricia; Gopalakrishna, Trisha; Hamsik, Marisa R.; Herrero, Mario; Kiesecker, Joseph; Landis, Emily; Laestadius, Lars; Leavitt, Sara M.; Minnemeyer, Susan; Polasky, Stephen; Potapov, Peter; Putz, Francis E.; Sanderman, Jonathan; Silvius, Marcel; Wollenberg, Eva; Fargione, Joseph
2017-10-01
Better stewardship of land is needed to achieve the Paris Climate Agreement goal of holding warming to below 2 °C; however, confusion persists about the specific set of land stewardship options available and their mitigation potential. To address this, we identify and quantify “natural climate solutions” (NCS): 20 conservation, restoration, and improved land management actions that increase carbon storage and/or avoid greenhouse gas emissions across global forests, wetlands, grasslands, and agricultural lands. We find that the maximum potential of NCS—when constrained by food security, fiber security, and biodiversity conservation—is 23.8 petagrams of CO2 equivalent (PgCO2e) y‑1 (95% CI 20.3–37.4). This is ≥30% higher than prior estimates, which did not include the full range of options and safeguards considered here. About half of this maximum (11.3 PgCO2e y‑1) represents cost-effective climate mitigation, assuming the social cost of CO2 pollution is ≥100 USD MgCO2e‑1 by 2030. Natural climate solutions can provide 37% of cost-effective CO2 mitigation needed through 2030 for a >66% chance of holding warming to below 2 °C. One-third of this cost-effective NCS mitigation can be delivered at or below 10 USD MgCO2‑1. Most NCS actions—if effectively implemented—also offer water filtration, flood buffering, soil health, biodiversity habitat, and enhanced climate resilience. Work remains to better constrain uncertainty of NCS mitigation estimates. Nevertheless, existing knowledge reported here provides a robust basis for immediate global action to improve ecosystem stewardship as a major solution to climate change.
Location Intelligence Solutions
International Nuclear Information System (INIS)
Schmidt, D.
2015-01-01
Location Intelligence (LI) means using the spatial dimension of information as a key to support business processes. This spatial dimension has to be defined by geographic coordinates. Storing these spatial objects in a database allows for attaching a 'meaning' to them, like 'current position', 'border', 'building' or 'room'. Now the coordinates represent real-world objects, which can be relevant for the measurement, documentation, control or optimization of (parameters of) business processes aiming at different business objectives. But LI can only be applied, if the locations can be determined with an accuracy (in space and time) appropriate for the business process in consideration. Therefore the first step in any development of a LI solution is the analysis of the business process itself regarding its requirements for spatial and time resolution and accuracy. The next step is the detailed analysis of the surrounding conditions of the process: Does the process happen indoor and/or outdoor? Are there moving objects? If yes, how fast are they? How does the relevant environment look like? Is technical infrastructure available? Is the process restricted by regulations? As a result, a proper Location Detection Technology (LDT) has to be chosen in order to get reliable and accurate positions of the relevant objects. At the highly challenging conditions of the business processes IAEA inspectors are working with, the chosen LDTs have to deliver reliable positioning on ''room-level'' accuracy, even if there is no location enabling infrastructure in place, the objects (people) mostly are indoors and have to work under strong regulations. The presentation will give insights into innovative LI solutions based on technologies of different LDT providers. Pros and cons of combinations of different LDT (like multi- GNSS, IMU, camera, and human interaction based positioning) will be discussed from the
Solute diffusivity in undisturbed soil
DEFF Research Database (Denmark)
Lægdsmand, Mette; Møldrup, Per; Schjønning, Per
2012-01-01
Solute diffusivity in soil plays a major role in many important processes with relation to plant growth and environmental issues. Soil solute diffusivity is affected by the volumetric water content as well as the morphological characteristics of water-filled pores. The solute diffusivity in intact...
Future climate. Engineering solutions
Energy Technology Data Exchange (ETDEWEB)
Ferdinand, J.F.; Hagedorn-Rasmussen, P.; Fonnesbech, B.
2009-09-15
Future Climate Engineering Solutions - Joint Report is the common output and a documentation of more than 1 year's effort by 13 engineering associations - in 12 countries - to demonstrate how technologies can combat climate change. The report consists of three parts: Summaries of 10 national climate plans and technology prospects, 5 Key Common Findings, and a Climate Call from Engineers to create a new global climate treaty. The basic assumption of the project is recognition that GHG emissions, and their concentration in the atmosphere, must be reduced to a sustainable level. The project definition of a sustainable level is equivalent to the best-case stabilisation scenario which was presented in the 4th Assessment Report (AR4) by the UN Intergovernmental Panel on Climate Change (IPCC), whereby the global mean temperature is most likely to stabilise at 2.0-2.4 deg. C. The Future Climate website www.futureclimate.info holds more information about the project, including possibility to download project material, including the full national climate plans.
International Nuclear Information System (INIS)
Burns, D.A.
1994-09-01
A fully automated analyzer has been developed for plutonium solutions. It was assembled from several commercially available modules, is based upon segmented flow analysis, and exhibits precision about an order of magnitude better than commercial units (0.5%-O.05% RSD). The system was designed to accept unmeasured, untreated liquid samples in the concentration range 40-240 g/L and produce a report with sample identification, sample concentrations, and an abundance of statistics. Optional hydraulics can accommodate samples in the concentration range 0.4-4.0 g/L. Operating at a typical rate of 30 to 40 samples per hour, it consumes only 0.074 mL of each sample and standard, and generates waste at the rate of about 1.5 mL per minute. No radioactive material passes through its multichannel peristaltic pump (which remains outside the glovebox, uncontaminated) but rather is handled by a 6-port, 2-position chromatography-type loop valve. An accompanying computer is programmed in QuickBASIC 4.5 to provide both instrument control and data reduction. The program is truly user-friendly and communication between operator and instrument is via computer screen displays and keyboard. Two important issues which have been addressed are waste minimization and operator safety (the analyzer can run in the absence of an operator, once its autosampler has been loaded)
International Nuclear Information System (INIS)
Silverstein, Eva
2008-01-01
We present a framework for de Sitter model building in type IIA string theory, illustrated with specific examples. We find metastable de Sitter (dS) minima of the potential for moduli obtained from a compactification on a product of two nil three-manifolds (which have negative scalar curvature) combined with orientifolds, branes, fractional Chern-Simons forms, and fluxes. As a discrete quantum number is taken large, the curvature, field strengths, inverse volume, and four-dimensional string coupling become parametrically small, and the de Sitter Hubble scale can be tuned parametrically smaller than the scales of the moduli, Kaluza Klein (KK), and winding mode masses. A subtle point in the construction is that although the curvature remains consistently weak, the circle fibers of the nilmanifolds become very small in this limit (though this is avoided in illustrative solutions at modest values of the parameters). In the simplest version of the construction, the heaviest moduli masses are parametrically of the same order as the lightest KK and winding masses. However, we provide a method for separating these marginally overlapping scales, and more generally the underlying supersymmetry of the model protects against large corrections to the low-energy moduli potential
Energy Technology Data Exchange (ETDEWEB)
Burns, D.A.
1994-09-01
A fully automated analyzer has been developed for plutonium solutions. It was assembled from several commercially available modules, is based upon segmented flow analysis, and exhibits precision about an order of magnitude better than commercial units (0.5%-O.05% RSD). The system was designed to accept unmeasured, untreated liquid samples in the concentration range 40-240 g/L and produce a report with sample identification, sample concentrations, and an abundance of statistics. Optional hydraulics can accommodate samples in the concentration range 0.4-4.0 g/L. Operating at a typical rate of 30 to 40 samples per hour, it consumes only 0.074 mL of each sample and standard, and generates waste at the rate of about 1.5 mL per minute. No radioactive material passes through its multichannel peristaltic pump (which remains outside the glovebox, uncontaminated) but rather is handled by a 6-port, 2-position chromatography-type loop valve. An accompanying computer is programmed in QuickBASIC 4.5 to provide both instrument control and data reduction. The program is truly user-friendly and communication between operator and instrument is via computer screen displays and keyboard. Two important issues which have been addressed are waste minimization and operator safety (the analyzer can run in the absence of an operator, once its autosampler has been loaded).
Insight solutions are correct more often than analytic solutions
Salvi, Carola; Bricolo, Emanuela; Kounios, John; Bowden, Edward; Beeman, Mark
2016-01-01
How accurate are insights compared to analytical solutions? In four experiments, we investigated how participants’ solving strategies influenced their solution accuracies across different types of problems, including one that was linguistic, one that was visual and two that were mixed visual-linguistic. In each experiment, participants’ self-judged insight solutions were, on average, more accurate than their analytic ones. We hypothesised that insight solutions have superior accuracy because they emerge into consciousness in an all-or-nothing fashion when the unconscious solving process is complete, whereas analytic solutions can be guesses based on conscious, prematurely terminated, processing. This hypothesis is supported by the finding that participants’ analytic solutions included relatively more incorrect responses (i.e., errors of commission) than timeouts (i.e., errors of omission) compared to their insight responses. PMID:27667960
Properties of scintillator solutes
International Nuclear Information System (INIS)
Fluornoy, J.M.
1998-06-01
This special report summarizes measurements of the spectroscopic and other properties of the solutes that were used in the preparation of several new liquid scintillators developed at EG and G/Energy Measurements/Santa Barbara Operations (the precursor to Bechtel Nevada/Special Technologies Laboratory) on the radiation-to-light converter program. The data on the individual compounds are presented in a form similar to that used by Prof. Isadore Berlman in his classic handbook of fluorescence spectra. The temporal properties and relative efficiencies of the new scintillators are presented in Table 1, and the efficiencies as a function of wavelength are presented graphically in Figure 1. In addition, there is a descriptive glossary of the abbreviations used herein. Figure 2 illustrates the basic structures of some of the compounds and of the four solvents reported in this summary. The emission spectra generally exhibit more structure than the absorption spectra, with the result that the peak emission wavelength for a given compound may lie several nm away from the wavelength, λ avg , at the geometric center of the emission spectrum. Therefore, the author has chosen to list absorption peaks, λ max , and emission λ avg values in Figures 3--30, as being most illustrative of the differences between the compounds. The compounds, BHTP, BTPB, ADBT, and DPTPB were all developed on this program. P-terphenyl, PBD, and TPB are commercially available blue emitters. C-480 and the other longer-wavelength emitters are laser dyes available commercially from Exciton Corporation. 1 ref., 30 figs
CEFR information management system solution
International Nuclear Information System (INIS)
Lu Fei; Zhao Jia'ning
2011-01-01
Based on finished information resources planning scheme for China sodium cooled experimental fast breeder reactor and the advanced information resources management solution concepts were applied, we got the building solution of CEFR information management systems. At the same time, the technical solutions of systems structures, logic structures, physical structures, development platforms and operation platforms for information resources management system in fast breeder reactors were developed, which provided programmatic introductions for development works in future. (authors)
Indium flotation from hydrometallurgical solutions
International Nuclear Information System (INIS)
Sviridov, V.V.; Mal'tsev, G.I.; Petryakova, N.K.; Gomzikov, A.I.
1980-01-01
The principal possibility of flotation of indium small quantities (10 -4 gxion/l) is established from sulphuric-acid solutions of leaching converter dusts of the copper melting production in the form of complex compounds with sodium hexametaphosphate and cation-active nitrogen-containing surfactants. It is shown that the flotation process effectiveness is determined by the molar ratio of hexametaphosphate and collector introduced into the solution, solution oxidity and surfactant nature
International Nuclear Information System (INIS)
Larkin, K.A.
1994-01-01
This test plan describes the activities associated with the High Gradient Magnetic Filtration (HGMF) of plutonium-bearing solutions (10-L). The 10-L solutions were received from Argonne National Laboratories in 1972, are highly acidic, and are considered unstable. The purpose of the testing is to show that HGMF is an applicable method of removing plutonium precipitates from solution. The plutonium then can be stored safely in a solid form
Structure and dynamics of solutions
Ohtaki, H
2013-01-01
Recent advances in the study of structural and dynamic properties of solutions have provided a molecular picture of solute-solvent interactions. Although the study of thermodynamic as well as electronic properties of solutions have played a role in the development of research on the rate and mechanism of chemical reactions, such macroscopic and microscopic properties are insufficient for a deeper understanding of fast chemical and biological reactions. In order to fill the gap between the two extremes, it is necessary to know how molecules are arranged in solution and how they change their pos
Enhanced safeguards via solution monitoring
International Nuclear Information System (INIS)
Burr, T.; Wangen, L.
1996-09-01
Solution monitoring is defined as the essentially continuous monitoring of solution level, density, and temperature in all tanks in the process that contain, or could contain, safeguards-significant quantities of nuclear material. This report describes some of the enhancements that solution monitoring could make to international safeguards. The focus is on the quantifiable benefits of solution monitoring, but qualitatively, solution monitoring can be viewed as a form of surveillance. Quantitatively, solution monitoring can in some cases improve diversion detection probability. For example, the authors show that under certain assumptions, solution monitoring can be used to reduce the standard deviation of the annual material balance, σ MB , from approximately 17 kg to approximately 4 kg. Such reduction in σ MB will not always be possible, as they discuss. However, in all cases, solution monitoring would provide assurance that the measurement error models are adequate so that one has confidence in his estimate of σ MB . Some of the results in this report were generated using data that were simulated with prototype solution monitoring software that they are developing. An accompanying document describes that software
Mckee, N
1983-10-01
Dr. Mujibur Rahaman, senior scientist at the International Center for Diarrheal Disease Research in Bangladesh, was interviewed recently in regard to oral rehydration therapy (ORT), a simple and inexpensive way of treating the loss of essential fluids and minerals that accompanies diarrhea. According to Rahaman, ORT, developed quite a while ago, is recently gaining more publicity and wider acceptance as a menas of replacing the water and electrolytes lost during acute diarrhea attack. The standard ingredients of the ORT mixture, as it is used in Bangladesh, are 3.5 gm of sodium chloride, or common salt, 2.5 gm sodium bicarbonate, and 1 gm of potassium chloride. To this one should add either 20 gm of glucose or 40 gm of sugar. This mixture should be dissolved in 1 liter of plain drinking water. Plain sugar is good enough. How much is needed depends on the severity and the duration of diarrhea. Calculations have shown that, as a rule of thumb, a child of 10-12 kg may require little more than a liter in about 24 hours. If the child has diarrhea of sufficient severity, it may require more than a liter. If the diarrhea is prolonged, it may require 2 liters. For children who are in danger of dying from dehydration, parents are warned to be watchful because further treatment and follow-up may be required. In Bangladesh a national program is currently providing the ORT in remote rural areas. At present about 1/3 of Bangladesh is covered. The national health service is distributing the solution free of cost in the villages where they have health volunteers. Although ORT is simple to make and simple to administer, one has to exercise some degree of caution with it in order to prevent infants getting dangerous symptoms like hypernatremia. ORT makes it possible for health educators to enter into the family. It is not totally correct to say water is the main problem or causative factor in producing diarrhea. In infantile diarrhea, the cause is most often a virus. Viral
International Nuclear Information System (INIS)
Galan Valera, M. P.; Acena Berrenechea, M. L.
1988-01-01
A method for as certain the activity by alpha spectroscopy with semiconductor detectors, of a solution of 232U is presented. It consists of the comparison with a 233U solution activity previously measured in a gridded ionization chamber of 2π geometry. The total measurement uncertainty is about + - 0,02. (Author) 9 refs
Calibration of uranium 232 solution
International Nuclear Information System (INIS)
Galan, M.P.; Acena, M.L.
1988-01-01
A method for acertainning the activity by alpha spectroscopy with semiconductor detectors, of a solution of Uranium-232 is presented. It consists of the comparison with a Uranium-233 solution activity previously measured in a gridded ionization chamber of 2 π geometry. The total measurement uncertainty is about +- 0,02. (Author)
Requirements Engineering: Solutions and Trends
Ebert, C.; Wieringa, Roelf J.; Aurum, A.; Wohlin, C.
2005-01-01
This last chapter of the book describes solutions and trends in the discipline of RE. Starting from a wrap-up of what was presented throughout this book, it suggests a framework of requirements engineering and indicates what current solutions are available in this framework. Beyond providing a short
International Nuclear Information System (INIS)
Corona-Corona, Gulmaro
2004-01-01
Based on the standard fact that any matrix potential u=u(x) determines a family of Jost solutions whose parameter runs analytically (continuously) on the (closed) half planes, respectively, the zeros of a suitable matrix valued Wronskian of a Jost solution pair are explored
Some exact Bradlow vortex solutions
Energy Technology Data Exchange (ETDEWEB)
Gudnason, Sven Bjarke [Institute of Modern Physics, Chinese Academy of Sciences,Lanzhou 730000 (China); Nitta, Muneto [Department of Physics, and Research and Education Center for Natural Sciences, Keio University,Hiyoshi 4-1-1, Yokohama, Kanagawa 223-8521 (Japan)
2017-05-08
We consider the Bradlow equation for vortices which was recently found by Manton and find a two-parameter class of analytic solutions in closed form on nontrivial geometries with non-constant curvature. The general solution to our class of metrics is given by a hypergeometric function and the area of the vortex domain by the Gaussian hypergeometric function.
Exploring manufacturing solutions for SMEs
DEFF Research Database (Denmark)
Radziwon, Agnieszka; Blichfeldt, Henrik; Bilberg, Arne
This exploratory study provides an overview over current state of manufacturing solutions in small and medium sized enterprises (SMEs) in region of Southern Denmark. Building on manufacturing paradigms, this paper reveals relevant aspects for the development and implementation of improving SMEs...... of manufacturing solutions, which are required to increase their competitiveness and assure sustainable growth....
Thermotransport in interstitial solid solutions
International Nuclear Information System (INIS)
Fogel'son, R.L.
1982-01-01
On the basis of literature data the problem of thermotransport of impurities (H, N, O, C) in interstitial solid solutions is considered. It is shown that from experimental data on the thermotransport an important parameter of dissolved atoms can be found which characterizes atom state in these solutions-enthalpy of transport
Analytic solutions of hydrodynamics equations
International Nuclear Information System (INIS)
Coggeshall, S.V.
1991-01-01
Many similarity solutions have been found for the equations of one-dimensional (1-D) hydrodynamics. These special combinations of variables allow the partial differential equations to be reduced to ordinary differential equations, which must then be solved to determine the physical solutions. Usually, these reduced ordinary differential equations are solved numerically. In some cases it is possible to solve these reduced equations analytically to obtain explicit solutions. In this work a collection of analytic solutions of the 1-D hydrodynamics equations is presented. These can be used for a variety of purposes, including (i) numerical benchmark problems, (ii) as a basis for analytic models, and (iii) to provide insight into more complicated solutions
Whole analogy between Daniel Bernoulli solution and direct kinematics solution
Directory of Open Access Journals (Sweden)
Filipović Mirjana
2010-01-01
Full Text Available In this paper, the relationship between the original Euler-Bernoulli's rod equation and contemporary knowledge is established. The solution which Daniel Bernoulli defined for the simplest conditions is essentially the solution of 'direct kinematics'. For this reason, special attention is devoted to dynamics and kinematics of elastic mechanisms configuration. The Euler-Bernoulli equation and its solution (used in literature for a long time should be expanded according to the requirements of the mechanisms motion complexity. The elastic deformation is a dynamic value that depends on the total mechanism movements dynamics. Mathematical model of the actuators comprises also elasticity forces.
Kumar, Rajeev Ananda; De, Priyadarsi; Zheng, Bin; Huang, Kuo-Wei; Emert, Jack I.; Faust, Rudolf
2015-01-01
The kinetics and mechanism of the polymerization of isobutylene catalyzed by FeCl3·ether complexes in hexane at 0°C were investigated. The polymerization rates increased in the diisopropyl ether< 2-chloroethyl ethyl ether < bis(2-chloroethyl) ether order, attributed to electronic effects. The polymerization rates increased with increasing initiator and catalyst concentrations. The first order plots, however, deviated from the linear suggesting that the cation concentration decreases with time. The previously proposed mechanism is inadequate to explain this finding. The decrease in the polymerization rate with time is explained by the low solubility of the H+ROR′FeCl4 - complexes that precipitate during polymerization. Based on mechanistic studies the revised mechanism now also includes the equilibrium H+ROR′FeCl4 - ⇋ HCl + FeCl3·ROR′.
Solutions for the food processing industry; Shokuhin seizogyo solution
Energy Technology Data Exchange (ETDEWEB)
Toda, T; Iwami, N [Fuji Electric Co. Ltd., Tokyo (Japan)
1999-09-10
To improve quality control and maintain stable operation, the food processing industry requires problem solutions in total, including not only processing and operation control divisions but also quality control, design and production technology, and maintenance divisions. This paper describes solutions for HACCP (hazard analysis critical control point) support, quality control, and maintenance, in order to improve the quality level, ensure traceability and realize stable processing operations. (author)
Indian Academy of Sciences (India)
Centrifugal blood pump 603 pressure obtained for real blood, as shown in figure 6, is a little higher than that for glycerin aqua Solution with the same viscosity as blood. This may indicate the effect of slight non-. Newtonian turbulent flow. The radial whirl motion of the impeller was observed by dual laser position sensors.
Anisotropic solutions by gravitational decoupling
Ovalle, J.; Casadio, R.; da Rocha, R.; Sotomayor, A.
2018-02-01
We investigate the extension of isotropic interior solutions for static self-gravitating systems to include the effects of anisotropic spherically symmetric gravitational sources by means of the gravitational decoupling realised via the minimal geometric deformation approach. In particular, the matching conditions at the surface of the star with the outer Schwarzschild space-time are studied in great detail, and we describe how to generate, from a single physically acceptable isotropic solution, new families of anisotropic solutions whose physical acceptability is also inherited from their isotropic parent.
Solution of the Baxter equation
International Nuclear Information System (INIS)
Janik, R.A.
1996-01-01
We present a method of construction of a family of solutions of the Baxter equation arising in the Generalized Leading Logarithmic Approximation (GLLA) of the QCD pomeron. The details are given for the exchange of N = 2 reggeons but everything can be generalized in a straightforward way to arbitrary N. A specific choice of solutions is shown to reproduce the correct energy levels for half integral conformal weights. It is shown that the Baxter's equation must be supplemented by an additional condition on the solution. (author)
Anisotropic solutions by gravitational decoupling
Energy Technology Data Exchange (ETDEWEB)
Ovalle, J. [Silesian University in Opava, Institute of Physics and Research Centre of Theoretical Physics and Astrophysics, Faculty of Philosophy and Science, Opava (Czech Republic); Universidad Simon Bolivar, Departamento de Fisica, Caracas (Venezuela, Bolivarian Republic of); Casadio, R. [Alma Mater Universita di Bologna, Dipartimento di Fisica e Astronomia, Bologna (Italy); Istituto Nazionale di Fisica Nucleare, Bologna (Italy); Rocha, R. da [Universidade Federal do ABC (UFABC), Centro de Matematica, Computacao e Cognicao, Santo Andre, SP (Brazil); Sotomayor, A. [Universidad de Antofagasta, Departamento de Matematicas, Antofagasta (Chile)
2018-02-15
We investigate the extension of isotropic interior solutions for static self-gravitating systems to include the effects of anisotropic spherically symmetric gravitational sources by means of the gravitational decoupling realised via the minimal geometric deformation approach. In particular, the matching conditions at the surface of the star with the outer Schwarzschild space-time are studied in great detail, and we describe how to generate, from a single physically acceptable isotropic solution, new families of anisotropic solutions whose physical acceptability is also inherited from their isotropic parent. (orig.)
Analytic Solutions and Resonant Solutions of Hyperbolic Partial Differential Equations
Wagenmaker, Timothy Roger
This dissertation contains two main subject areas. The first deals with solutions to the wave equation Du/Dt + a Du/Dx = 0, where D/Dt and D/Dx represent partial derivatives and a(t,x) is real valued. The question I studied, which arises in control theory, is whether solutions which are real analytic with respect to the time variable are dense in the space of all solutions. If a is real analytic in t and x, the Cauchy-Kovalevsky Theorem implies that the solutions real analytic in t and x are dense, since it suffices to approximate the initial data by polynomials. The same positive result is valid when a is continuously differentiable and independent of t. This is proved by regularization in time. The hypothesis that a is independent of t cannot be replaced by the weaker assumption that a is real analytic in t, even when it is infinitely smooth. I construct a(t,x) for which the solutions which are analytic in time are automatically periodic in time. In particular these solutions are not dense in the space of all solutions. The second area concerns the resonant interaction of oscillatory waves propagating in a compressible inviscid fluid. An asymptotic description given by Andrew Majda, Rodolfo Rosales, and Maria Schonbek (MRS) involves the genuinely nonlinear quasilinear hyperbolic system Du/Dt + D(uu/2)/Dt + v = 0, Dv/Dt - D(vv/2)/Dt - u = 0. They performed many numerical simulations which indicated that small amplitude solutions of this system tend to evade shock formation, and conjectured that "smooth initial data with a sufficiently small amplitude never develop shocks throughout a long time interval of integration.". I proved that for smooth periodic U(x), V(x) and initial data u(0,x) = epsilonU(x), v(0,x) = epsilonV(x), the solution is smooth for time at least constant times | ln epsilon| /epsilon. This is longer than the lifetime order 1/ epsilon of the solution to the decoupled Burgers equations. The decoupled equation describes nonresonant interaction of
Patient Education Sheet Simple Solutions for Dry Eye The SSF thanks J. Daniel Nelson, MD, Associate Medical Director, Specialty Care HealthPartners Medical Group & Clinics, and Professor of Ophthalmology, University of ...
International Nuclear Information System (INIS)
Atkinson, James; Nijhoff, Frank; Hietarinta, Jarmo
2008-01-01
We construct N-soliton solutions to the equation called Q3 in the recent Adler-Bobenko-Suris classification. An essential ingredient in the construction is the relationship of (Q3) δ=0 to the equation proposed by Nijhoff, Quispel and Capel in 1983 (the NQC equation). This latter equation has two extra parameters, and depending on their sign choices we get a 4-to-1 relationship from NQC to (Q3) δ=0 . This leads to a four-term background solution, and then to a 1-soliton solution using a Baecklund transformation. Using the 1SS as a guide allows us to get the N-soliton solution in terms of the τ-function of the Hirota-Miwa equation. (fast track communication)
Clean Energy Solutions Center Services
Energy Technology Data Exchange (ETDEWEB)
2016-03-01
The Solutions Center offers no-cost expert policy assistance, webinars and training forums, clean energy policy reports, data, and tools provided in partnership with more than 35 leading international and regional clean energy organizations.
Exact cosmological solutions for MOG
International Nuclear Information System (INIS)
Roshan, Mahmood
2015-01-01
We find some new exact cosmological solutions for the covariant scalar-tensor-vector gravity theory, the so-called modified gravity (MOG). The exact solution of the vacuum field equations has been derived. Also, for non-vacuum cases we have found some exact solutions with the aid of the Noether symmetry approach. More specifically, the symmetry vector and also the Noether conserved quantity associated to the point-like Lagrangian of the theory have been found. Also we find the exact form of the generic vector field potential of this theory by considering the behavior of the relevant point-like Lagrangian under the infinitesimal generator of the Noether symmetry. Finally, we discuss the cosmological implications of the solutions. (orig.)
Solute carrier transporters: Pharmacogenomics research ...
African Journals Online (AJOL)
Aghogho
2010-12-27
Dec 27, 2010 ... This paper reviews the solute carrier transporters and highlights the fact that there is much to be learnt from .... transporters, drug targets, effect or proteins and meta- ... basolateral or apical plasma membrane of polarized cells,.
Transnistria: Prospects for a Solution
National Research Council Canada - National Science Library
Urse, Cristian
2007-01-01
.... After the conclusion of the agreement that ended the armed conflict, Chisinau and Tiraspol made efforts to find a political solution, under the supervision of a negotiation mechanism that included...
Anthology of dry storage solutions
Energy Technology Data Exchange (ETDEWEB)
Allimann, Nathalie; Otton, Camille [AREVA, Paris (France)
2012-03-15
Around 35,000 PWR, BWR or Veer used fuel elements with various enrichment value up to 5%, various cooling time down to 2 years and various burn-ups up to 60,000 Mwd/tU are currently stored in AREVA dry storage solutions. These solutions are delivered in the United States, in Japan and in many European countries like Belgium, Switzerland, Italy, Armenia and Germany. With more than 1000 dry storage solutions delivered all over the world AREVA is the leader on this market. Dealing with dry storage is not an easy task. Products have to be flexible, to be adapted to customer needs and to the national regulations which may stipulate very strict tests such as airplane crash or simulation of earthquake. To develop a dry storage solution for a foreign country means to deal with its national competent authorities. All the national competent authorities do not have the same requirements. Storage conditions may also be different.
Anthology of dry storage solutions
International Nuclear Information System (INIS)
Allimann, Nathalie; Otton, Camille
2012-01-01
Around 35,000 PWR, BWR or Veer used fuel elements with various enrichment value up to 5%, various cooling time down to 2 years and various burn-ups up to 60,000 Mwd/tU are currently stored in AREVA dry storage solutions. These solutions are delivered in the United States, in Japan and in many European countries like Belgium, Switzerland, Italy, Armenia and Germany. With more than 1000 dry storage solutions delivered all over the world AREVA is the leader on this market. Dealing with dry storage is not an easy task. Products have to be flexible, to be adapted to customer needs and to the national regulations which may stipulate very strict tests such as airplane crash or simulation of earthquake. To develop a dry storage solution for a foreign country means to deal with its national competent authorities. All the national competent authorities do not have the same requirements. Storage conditions may also be different
Rapidly Deployable Mobile Security Solution
2016-03-01
Chapter V, but Android provides default onboard encryption and it is an optional feature for removable media. Wipe the device (to scrub its stored...Mobile Data Solution Since Android has removed the ability to control mobile data, and it is unknown if a creative solution to shut this feature...down exists, then some exploration on this topic is warranted. Android removed the access to this feature under the auspices of preventing
Reuse of hydroponic waste solution.
Kumar, Ramasamy Rajesh; Cho, Jae Young
2014-01-01
Attaining sustainable agriculture is a key goal in many parts of the world. The increased environmental awareness and the ongoing attempts to execute agricultural practices that are economically feasible and environmentally safe promote the use of hydroponic cultivation. Hydroponics is a technology for growing plants in nutrient solutions with or without the use of artificial medium to provide mechanical support. Major problems for hydroponic cultivation are higher operational cost and the causing of pollution due to discharge of waste nutrient solution. The nutrient effluent released into the environment can have negative impacts on the surrounding ecosystems as well as the potential to contaminate the groundwater utilized by humans for drinking purposes. The reuse of non-recycled, nutrient-rich hydroponic waste solution for growing plants in greenhouses is the possible way to control environmental pollution. Many researchers have successfully grown several plant species in hydroponic waste solution with high yield. Hence, this review addresses the problems associated with the release of hydroponic waste solution into the environment and possible reuse of hydroponic waste solution as an alternative resource for agriculture development and to control environmental pollution.
Radiolysis of Aqueous Toluene Solutions
Energy Technology Data Exchange (ETDEWEB)
Christensen, H C; Gustafson, R
1971-04-15
Aqueous toluene solutions have been irradiated with Co gamma-rays. In unbuffered solutions the various cresol isomers are formed in a total yield of 0.45, 0.87 and 0.94 molecules/100 eV absorbed energy in argon-, N{sub 2}O- and air - saturated solutions, respectively. The yields are reduced in acid (pH 3) solutions (G = 0.14, 0.14 and 0.52, respectively) but the reduction is compensated by the formation of 1,2-di-phenylethane in yields of 0.49 and 1.60 in argon- and N{sub 2}O-saturated solutions, respectively. Benzyl radicals are formed through an acid catalysed water elimination reaction from the initially formed hydroxymethylcyclohexadienyl radical. Phenyltolylmethanes, dimethylbiphenyls and partly reduced dimers are also formed during the radiolysis. Hydrogen is formed in the same yield as the molecular yield, g(H{sub 2}). Xylene isomers and benzene are formed in trace quantities. The most remarkable effects of the addition of Fe(III) ions to deaerated acid toluene solutions are the formation of benzyl alcohol and benzaldehyde and an increase in the yield of 1,2-diphenylethane
Radiolysis of Aqueous Toluene Solutions
International Nuclear Information System (INIS)
Christensen, H.C.; Gustafson, R.
1971-04-01
Aqueous toluene solutions have been irradiated with Co γ-rays. In unbuffered solutions the various cresol isomers are formed in a total yield of 0.45, 0.87 and 0.94 molecules/100 eV absorbed energy in argon-, N 2 O- and air - saturated solutions, respectively. The yields are reduced in acid (pH 3) solutions (G 0.14, 0.14 and 0.52, respectively) but the reduction is compensated by the formation of 1,2-di-phenylethane in yields of 0.49 and 1.60 in argon- and N 2 O-saturated solutions, respectively. Benzyl radicals are formed through an acid catalysed water elimination reaction from the initially formed hydroxymethylcyclohexadienyl radical. Phenyltolylmethanes, dimethylbiphenyls and partly reduced dimers are also formed during the radiolysis. Hydrogen is formed in the same yield as the molecular yield, g(H 2 ). Xylene isomers and benzene are formed in trace quantities. The most remarkable effects of the addition of Fe(III) ions to deaerated acid toluene solutions are the formation of benzyl alcohol and benzaldehyde and an increase in the yield of 1,2-diphenylethane
Technetium recovery from high alkaline solution
Energy Technology Data Exchange (ETDEWEB)
Nash, Charles A.
2016-07-12
Disclosed are methods for recovering technetium from a highly alkaline solution. The highly alkaline solution can be a liquid waste solution from a nuclear waste processing system. Methods can include combining the solution with a reductant capable of reducing technetium at the high pH of the solution and adding to or forming in the solution an adsorbent capable of adsorbing the precipitated technetium at the high pH of the solution.
Radiolysis of Aqueous Benzene Solutions
Energy Technology Data Exchange (ETDEWEB)
Christensen, H
1964-05-15
Aerated and deaerated aqueous solutions of benzene have been irradiated with {sup 60}Co {gamma}-rays. The products of radiolysis in deaerated, unbuffered or acid, solutions were phenol, biphenyl, hydrogen and in acid solutions also hydrogen peroxide with the following yields: G(phenol) = 0. 37 (0. 37), G(biphenyl) = 1.3 (1.7), G(H{sub 2}) = 0.44 (0. 43) and G(H{sub 2}O{sub 2}) = 0 (0.60), the figures in brackets giving the results for acid solutions. The results are shown to agree with the conclusion that k(e{sup -}{sub aq} + H{sub 2}O{sub 2}) >> k(H + H{sub 2}O{sub 2}). Furthermore, the results indicate that a competition takes place between the reactions: 2 C{sub 6}H{sub 6}OH {center_dot} -> dimer -> biphenyl. C{sub 6}H{sub 7} {center_dot} + C{sub 6}H{sub 6}OH {center_dot} -> dimer -> biphenyl. The yields in aerated, unbuffered or acid, solutions were: G(phenol) = 2.1 (2.3), G(biphenyl) = 0 (0), and G(H{sub 2}O{sub 2}) = 2.2 (3.1), the figures in brackets being valid for acid solutions. The ratio k(H + C{sub 6}H{sub 6})/k(H + O{sub 2}) was 1.4x10{sup -2}. The results indicate that peroxides, or more probably hydroperoxides, take part in the reactions. After the addition of Fe{sup 2+} or Fe{sup 3+} to aerated acid solutions G(phenol) was increased to 6.6 and 3.4 respectively. Oxygen was consumed more rapidly in the presence of Fe. Reaction mechanisms are discussed.
Czech Academy of Sciences Publication Activity Database
Sajfrtová, Marie; Sovová, Helena
2012-01-01
Roč. 42, SI (2012), s. 1682-1691 E-ISSN 1877-7058. [International Congress of Chemical and Process Engineering CHISA 2012 and 15th Conference PRES 2012 /20./. Prague, 25.08.2012-29.08.2012] R&D Projects: GA TA ČR TA01010578 Institutional support: RVO:67985858 Keywords : supercritical fluid extraction * sea buckthom leaves * solute-solute interaction Subject RIV: CI - Industrial Chemistry, Chemical Engineering
Solidification of radioactive aqueous solution
Energy Technology Data Exchange (ETDEWEB)
Aikawa, Hideaki; Kato, Kiyoshi; Wadachi, Yoshiki
1970-09-07
A process for solidifying a radioactive waste solution is provided, using as a solidifying agent a mixture of calcined gypsum and burnt vermiculite. The quantity ratio of the mixture is preferred to be 1:1 by volume. The quantity of impregnation is 1/2 of the volume of the total quantity of the solidifying agent. In embodiments, 10 liters of plutonium waste solution was mixed with a mixture of 1:1 calcined gypsum and burnt vermiculite contained in a 20-liter cylindrical steel container lined with asphalt. The plutonium waste solution from the laboratory was neutralized with a caustic soda aqueous solution to prevent explosion due to the nitration of organic compounds. The neutralization is not always necessary. A market available dental gypsum was calcined at 400 to 500/sup 0/C and a vermiculite from Illinois was burnt at 1,100/sup 0/C to prepare the agents. The time required for the impregnation with 10 liters of plutonium solution was four minutes. After impregnation, the temperature rose to 40/sup 0/C within 30 minutes to one hour. Next, it was cooled to room temperature by standing for 3-4 hours. Solidification time was about 1 hour. The Japan Atomic Energy Research Insitute had treated and disposed about 1,000 tons of plutonium waste by this process as of August 19, 1970.
Project Management Plan Solution Stabilization
Energy Technology Data Exchange (ETDEWEB)
SATO, P.K.
1999-08-31
This plan presents the overall objectives, description, justification and planning for the Plutonium Finishing Plant (PFP) Solutions Stabilization subproject. The intent of this plan is to describe how this project will be managed and integrated with other facility stabilization and deactivation activities. This plan supplements the overall integrated plan presented in the Integrated Project Management Plan (IPMP) for the Plutonium Finishing Plant Stabilization and Deactivation Project, HNF-3617. This project plan is the top-level definitive project management document for the PFP Solution Stabilization subproject. It specifies the technical, schedule, requirements and the cost baselines to manage the execution of the Solution Stabilization subproject. Any deviations to the document must be authorized through the appropriate change control process.
Project Management Plan Solution Stabilization
International Nuclear Information System (INIS)
SATO, P.K.
1999-01-01
This plan presents the overall objectives, description, justification and planning for the Plutonium Finishing Plant (PFP) Solutions Stabilization subproject. The intent of this plan is to describe how this project will be managed and integrated with other facility stabilization and deactivation activities. This plan supplements the overall integrated plan presented in the Integrated Project Management Plan (IPMP) for the Plutonium Finishing Plant Stabilization and Deactivation Project, HNF-3617. This project plan is the top-level definitive project management document for the PFP Solution Stabilization subproject. It specifies the technical, schedule, requirements and the cost baselines to manage the execution of the Solution Stabilization subproject. Any deviations to the document must be authorized through the appropriate change control process
Plagiarism Detection by Online Solutions.
Masic, Izet; Begic, Edin; Dobraca, Amra
2017-01-01
The problem of plagiarism represents one of the burning issues of the modern scientific world. Detection of plagiarism is a problem that the Editorial Board encounters in their daily work. Software solutions represent a good solution for the detection of plagiarism. The problem of plagiarism will become most discussed topic of the modern scientific world, especially due to the development of standard measures, which rank the work of one author. Investment in education, education of young research personnel about the importance of scientific research, with paying particular attention on ethical behavior, becomes an imperative of academic staff. Editors have to invest additional effort in the development of the base of reviewers team as well as in their proper guidance, because after all, despite the software solutions, they are the best weapon to fight plagiarism. Peer review process should be a key of successful operation of each journal.
Device for analyzing a solution
International Nuclear Information System (INIS)
Marchand, Joseph.
1978-01-01
The device enables a solution containing an antigen to be analyzed by the radio-immunology technique without coming up against the problems of antigen-antibody complex and free antigen separation. This device, for analyzing a solution containing a biological compound capable of reacting with an antagonistic compound specific of the biological compound, features a tube closed at its bottom end and a component set and immobilized in the bottom of the tube so as to leave a capacity between the bottom of the tube and its lower end. The component has a large developed surface and is so shaped that it allows the solution to be analyzed to have access to the bottom of the tube; it is made of a material having some elastic deformation and able to take up a given quantity of the biological compound or of the antagonistic compound specific of the biological compound [fr
Analytical Solution of Multicompartment Solute Kinetics for Hemodialysis
Directory of Open Access Journals (Sweden)
Przemysław Korohoda
2013-01-01
Full Text Available Objective. To provide an exact solution for variable-volume multicompartment kinetic models with linear volume change, and to apply this solution to a 4-compartment diffusion-adjusted regional blood flow model for both urea and creatinine kinetics in hemodialysis. Methods. A matrix-based approach applicable to linear models encompassing any number of compartments is presented. The procedure requires the inversion of a square matrix and the computation of its eigenvalues λ, assuming they are all distinct. This novel approach bypasses the evaluation of the definite integral to solve the inhomogeneous ordinary differential equation. Results. For urea two out of four eigenvalues describing the changes of concentrations in time are about 105 times larger than the other eigenvalues indicating that the 4-compartment model essentially reduces to the 2-compartment regional blood flow model. In case of creatinine, however, the distribution of eigenvalues is more balanced (a factor of 102 between the largest and the smallest eigenvalue indicating that all four compartments contribute to creatinine kinetics in hemodialysis. Interpretation. Apart from providing an exact analytic solution for practical applications such as the identification of relevant model and treatment parameters, the matrix-based approach reveals characteristic details on model symmetry and complexity for different solutes.
Solution chemistry and separation of metal ions in leached solution
International Nuclear Information System (INIS)
Shibata, J.
1991-01-01
The method to presume a dissolved state of metal ions in an aqueous solution and the technology to separate and concentrate metal ions in a leached solution are described in this paper. It is very important for the separation of metal ions to know the dissolved state of metal ions. If we know the composition of an aqueous solution and the stability constants of metal-ligand complexes, we can calculate and estimate the concentration of each species in the solution. Then, we can decide the policy to separate and concentrate metal ions. There are several methods for separation and purification; hydroxide precipitation method, sulfide precipitation method, solvent extraction method and ion exchange resin method. Solvent extraction has been used in purification processes of copper refinery, uranium refinery, platinum metal refinery and rare earth metal refinery. Fundamental process of solvent extraction, a kind of commercial extractants, a way of determining a suitable extractant and an equipment are discussed. Finally, it will be emphasized how the separation of rare earths is improved in solvent extraction. (author) 21 figs., 8 tabs., 8 refs
Fundamental solutions of singular SPDEs
International Nuclear Information System (INIS)
Selesi, Dora
2011-01-01
Highlights: → Fundamental solutions of linear SPDEs are constructed. → Wick-convolution product is introduced for the first time. → Fourier transformation maps Wick-convolution into Wick product. → Solutions of linear SPDEs are expressed via Wick-convolution with fundamental solutions. → Stochastic Helmholtz equation is solved. - Abstract: This paper deals with some models of mathematical physics, where random fluctuations are modeled by white noise or other singular Gaussian generalized processes. White noise, as the distributional derivative od Brownian motion, which is the most important case of a Levy process, is defined in the framework of Hida distribution spaces. The Fourier transformation in the framework of singular generalized stochastic processes is introduced and its applications to solving stochastic differential equations involving Wick products and singularities such as the Dirac delta distribution are presented. Explicit solutions are obtained in form of a chaos expansion in the Kondratiev white noise space, while the coefficients of the expansion are tempered distributions. Stochastic differential equations of the form P(ω, D) ◊ u(x, ω) = A(x, ω) are considered, where A is a singular generalized stochastic process and P(ω, D) is a partial differential operator with random coefficients. We introduce the Wick-convolution operator * which enables us to express the solution as u = s*A ◊ I ◊(-1) , where s denotes the fundamental solution and I is the unit random variable. In particular, the stochastic Helmholtz equation is solved, which in physical interpretation describes waves propagating with a random speed from randomly appearing point sources.
Study of liquids and solutions
International Nuclear Information System (INIS)
Bellissent-Funel, M.C.
1994-01-01
A critical review of what has been achieved on the structure of liquids and solutions and the capabilities and developments of neutron scattering in this domain, are presented. A great variety of simple to complex systems has been investigated with the aim of obtaining a full microscopic description of the structure. Selected examples demonstrate the neutron scattering determination of interaction potentials, intermolecular structures and partial structure factors of complex systems. The isotopic substitution method is illustrated by the application to the study of the solvation of ions in aqueous and non aqueous solutions. (author). 9 figs., 32 refs
Schwarzschild Solution: A Historical Perspective
Bartusiak, Marcia
2016-03-01
While eighteenth-century Newtonians had imagined a precursor to the black hole, the modern version has its roots in the first full solution to Einstein's equations of general relativity, derived by the German astronomer Karl Schwarzschild on a World War I battlefront just weeks after Einstein introduced his completed theory in November 1915. This talk will demonstrate how Schwarzschild's solution is linked to the black hole and how it took more than half a century for the physics community to accept that such a bizarre celestial object could exist in the universe.
Electrodialysis operation with buffer solution
Hryn, John N [Naperville, IL; Daniels, Edward J [Orland Park, IL; Krumdick, Greg K [Crete, IL
2009-12-15
A new method for improving the efficiency of electrodialysis (ED) cells and stacks, in particular those used in chemical synthesis. The process entails adding a buffer solution to the stack for subsequent depletion in the stack during electrolysis. The buffer solution is regenerated continuously after depletion. This buffer process serves to control the hydrogen ion or hydroxide ion concentration so as to protect the active sites of electrodialysis membranes. The process enables electrodialysis processing options for products that are sensitive to pH changes.
Magnetic Half-Monopole Solutions
International Nuclear Information System (INIS)
Teh, Rosy; Lim, Kok-Geng; Koh, Pin-Wai
2009-01-01
We present exact SU(2) Yang-Mills-Higgs monopole solutions of one half topological charge. These non-Abelian solutions possess gauge potentials which are singular along either the positive or the negative z-axis and common magnetic fields that are singular only at the origin where the half-monopole is located. These half-monopoles are actually a half Wu-Yang monopole and they can possess a finite point electric charge and become half-dyons. They do not necessarily satisfy the first order Bogomol'nyi equations and they possess infinite energy density at r = 0.
Teaching sustainable solutions in engineering
DEFF Research Database (Denmark)
Olsen, Stig Irving; Nielsen, Susanne Balslev; Ejlertsen, Marina
2015-01-01
's study lines. The objectives of the course 'Sustainability in engineering solutions', is for the participants to understand the basic concept of sustainability and its three dimensions (people, profit, planet), as well as to analyse problems and synthesise solutions that are sustainable throughout...... their life cycle. The course runs over a full time 3-week period and employs project-based learning with several sub-projects/-problems. This paper takes an in-depth discussion of the considerations concerning how to teach such a complicated subject to students of widely differing backgrounds, and reflects...
Fluid mechanics problems and solutions
Spurk, Joseph H
1997-01-01
his collection of over 200 detailed worked exercises adds to and complements the textbook Fluid Mechanics by the same author, and illustrates the teaching material through examples. In the exercises the fundamental concepts of Fluid Mechanics are applied to obtaining the solution of diverse concrete problems, and in doing this the student's skill in the mathematical modeling of practical problems is developed. In addition, 30 challenging questions without detailed solutions have been included, and while lecturers will find these questions suitable for examinations and tests, the student himself can use them to check his understanding of the subject.
Zeglinski, Jacek; Kuhs, Manuel; Khamar, Dikshitkumar; Hegarty, Avril C; Devi, Renuka K; Rasmuson, Åke C
2018-04-03
The influence of the solvent in nucleation of tolbutamide, a medium-sized, flexible and polymorphic organic molecule, has been explored by measuring nucleation induction times, estimating solvent-solute interaction enthalpies using molecular modelling and calorimetric data, probing interactions and clustering with spectroscopy, and modelling solvent-dependence of molecular conformation in solution. The nucleation driving force required to reach the same induction time is strongly solvent-dependent, increasing in the order: acetonitrilenucleation difficulty is a function of the strength of solvent-solute interaction, with emphasis on the interaction with specific H-bonding polar sites of importance in the crystal structure. A clear exception from this rule is the most difficult nucleation in toluene despite the weakest solvent-solute interactions. However molecular dynamics modelling predicts that tolbutamide assumes an intramolecularly H-bonded conformation in toluene, substantially different from and more stable than the conformation in the crystal structure, and thus presenting an additional barrier to nucleation. This explains why nucleation in toluene is the most difficult and why the relatively higher propensity for aggregation of tolbutamide molecules in toluene solution, as observed with FTIR spectroscopy, does not translate into easier nucleation. Thus, our combined experimental and molecular modelling study suggests that the solvent can influence on the nucleation not only via differences in the desolvation but also through the influence on molecular conformation. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Numerical Asymptotic Solutions Of Differential Equations
Thurston, Gaylen A.
1992-01-01
Numerical algorithms derived and compared with classical analytical methods. In method, expansions replaced with integrals evaluated numerically. Resulting numerical solutions retain linear independence, main advantage of asymptotic solutions.
Some new radiating Kerr-Newman solutions
International Nuclear Information System (INIS)
Patel, L.K.; Singh, Tajinder; Koppar, S.S.
1991-01-01
Three exact non-static solutions of Einstein-Maxwell equations corresponding to a field of flowing null radiation plus an electromagnetic field are presented. These solutions are non-static generalizations of the well known Kerr-Newman solution. The current vector is null in all the three solutions. These solutions are the electromagnetic generalizations of the three generalized radiating Kerr solutions discussed by Vaidya and Patel. The solutions discussed here describe the exterior gravitational fields of rotating radiating charged bodies. Many known solutions are derived as particular cases. (author). 12 refs
Siemens IT solutions for power sector
International Nuclear Information System (INIS)
Lunter, P.
2004-01-01
The cost reduction, flexibility and revenue increase, potential exploitation, productivity increase, and business opportunities exploitation - that is all what can be required in the races for the promonent positioning on the electricity power market. These requirements can be realized by the sophisticated IT solutions hand-tailored to the special requirements of the electric power producers and tradesmen. This approach makes it possible to achieve greater profit. Our solutions 'PROFIT Solutions', that are symbiosis of the most progressive information technologies and the power plant techniques of the company Siemens, satisfy submitted specifications in substantial measure. The system solutions 'PROFIT Solutions' comprise three solution groups: process, operation a business. The solutions of the group 'IT Process Solutions' increase flexibility and manoeuvrability of equipment, improve the efficiency and contribute to more economical operation of the power generation. Solutions 'IT Process Solutions' simplify and shorten the period of power cycles and conduce to higher labour productivity. Solutions group 'IT Process Solutions' approaches equipment to the market - supports the profit strategies, helps quickly and expertly to determine and predict hazards. The extension PROFIT Cockpit means the nuance to the solutions world 'PROFIT Solutions'. The survey about the whole installation is within reach at the simple touch of a button. It is possible to compile the total system part by part from single solutions 'PROFIT Solutions'. As a matter of fact all single parts can be interconnected with already existing solutions. Routines 'PROFIT Solutions' cooperate with all modern control systems. (author)
Business value of solution architecture
Slot, R.; Dedene, G.; Maes, R.; Proper, E.; Harmsen, F.; Dietz, J.L.G.
2009-01-01
The theory and especially the practice of IT architecture have been developed quite vigorously the last years. However, hardly any quantitative data about the value of IT architecture is available. This paper presents the results of a study, which measures the value of IT solution architecture for
COMPOSITE SOLUTIONS IN RAILROAD ENGINEERING
Directory of Open Access Journals (Sweden)
Panfilova Marina Ivanovna
2012-10-01
Full Text Available Present-day methods of recovery of used wooden railway ties, including burial, chemical neutralization, gasification and subsequent burning, utilization in the capacity of composite materials, are expensive and unsafe for the environment. The authors propose a new method of their utilization. Ash generated in the course of their burning may replace a portion of cement in composite solutions and act as an additive to grouting mortars designated for the filling of the annulus space of manifold tunnels. The chemical composition of the ash was identified by the x-ray method applied to three samples taken during various periods of time from out of a dry-type dust collector. The level of human health/environmental hazard of the ash is based on its chemical composition. Changes in the rheological properties of composite solutions that contained concrete fractions, various ratios of ash, and 5% of liquid glass were studied in the course of the research. The experiments have proven that in the event of replacement of 20% of cement by ash, the strength of the composite solution is approximately the same as the one of the benchmark sample; therefore, this ash content ratio is deemed acceptable. The finding demonstrate that the ash has no toxic effect, and the ecological safety of this solution is thus confirmed. The authors have proven that 20% of cement may be replaced by the ash generated in the course of burning of waste railway ties.
Aqueous Solution Chemistry of Plutonium
Energy Technology Data Exchange (ETDEWEB)
Clark, David L. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2014-01-28
Things I have learned working with plutonium: Chemistry of plutonium is complex; Redox equilibria make Pu solution chemistry particularly challenging in the absence of complexing ligands; Understanding this behavior is key to successful Pu chemistry experiments; There is no suitable chemical analog for plutonium.
Negative energy solutions and symmetries
International Nuclear Information System (INIS)
Sidharth, B.G.
2011-01-01
We revisit the negative energy solutions of the Dirac (and Klein–Gordon) equation, which become relevant at very high energies in the context of the Feshbach–Villars formulation, and study several symmetries which follow therefrom. Significant consequences are briefly examined. (author)
Scorpion toxins prefer salt solutions
Czech Academy of Sciences Publication Activity Database
Nikouee, A.; Khabiri, Morteza; Cwiklik, Lukasz
2015-01-01
Roč. 21, č. 11 (2015), 287/1-287/14 ISSN 1610-2940 R&D Projects: GA ČR GA13-06181S Institutional support: RVO:61388963 ; RVO:61388955 Keywords : ionic solutions * molecular dynamics * nonaqueous media * secondary structure Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.438, year: 2015
In situ solution mining technique
International Nuclear Information System (INIS)
Learmont, R.P.
1978-01-01
A method of in situ solution mining is disclosed in which a primary leaching process employing an array of 5-spot leaching patterns of production and injection wells is converted to a different pattern by converting to injection wells all the production wells in alternate rows
A pyramid solution at Chernobyl
International Nuclear Information System (INIS)
Anon.
1994-01-01
In the Kiev '92 competition to find a solution to the problem of containing the stricken Chernobyl unit 4, the PPROTECTOR proposal, put forward by a British-led international consortium, ranked fifth after the first round of judging. It made extensive use of advanced CAD techniques. (Author)
Solution chemistry of lanthanide complexes
International Nuclear Information System (INIS)
Brittain, H.G.
1979-01-01
Intermolecular energy transfer from Tb 3+ to Eu 3+ , luminescence intensity measurements, potentiometric titrations, differential absorption spectroscopy, and spectroscopic titrations were all used to study the binding of lanthanide ions by serine and threonine. At low pH (3.0 to 6.0) the complexes are mononuclear and ligand is only weakly bound. In the pH interval of 6.0 to 8.5 stronger interaction takes place between the ligand and the metal (with possible coordination of the undissociated hydroxyl group), and self-association of complexes becomes important. Above pH 8.5, base hydrolysis of the complexes leads to highly associated species in solution and shortly above this pH an insoluble precipitate is formed. It was found that energy could be transferred from Tb 3+ to Eu 3+ more efficiently among complexes prepared from racemic ligands than in complexes made from resolved ligand, but this stereoselectivity was only observed at pH values greater than 6.5 and in solutions having a 1:10 ratio of metal-to-ligand. No stereoselectivity was found in solutions having 1:5 ratios, and this observation was explained by the existence of 1:2 metal-ligand complexes existing in solutions having the higher ratio of metal-to-ligand (only 1:1 complexes are then found at lower ratios of metal-to-ligand). (author)
Hospitality lighting solutions communication framework
Blanch, Anna
2014-01-01
Hospitality customers are looking for systems that involve more than just turning the light on and off. They want lighting solutions that are energy-efficient, flexible and that will help enhance the guest experience. Based on on-going research about the impact that light can have in different
Looking to nature for solutions
Turner, Will R.
2018-01-01
Completely stopping fossil fuel use may not be enough to avoid dangerous climate change. Recent research on the mitigation potential of conservation, restoration, and improved land management demonstrates that natural solutions can reduce emissions and remove atmospheric CO2 while safeguarding food security and biodiversity.
Decomposition of metal nitrate solutions
International Nuclear Information System (INIS)
Haas, P.A.; Stines, W.B.
1982-01-01
Oxides in powder form are obtained from aqueous solutions of one or more heavy metal nitrates (e.g. U, Pu, Th, Ce) by thermal decomposition at 300 to 800 deg C in the presence of about 50 to 500% molar concentration of ammonium nitrate to total metal. (author)
Statistical mechanics of protein solutions
Prinsen, P.
2007-01-01
We study theoretically thermodynamic properties of spherical globular proteins in aqueous solution with added monovalent salt. We show how one can determine an effective interaction potential between the proteins from experimental data as a function of salt concentration and we apply this to the
International Nuclear Information System (INIS)
Ormancey, E
2008-01-01
The need for Single Sign On has always been restricted by the absence of cross platform solutions: a single sign on working only on one platform or technology is nearly useless. The recent improvements in Web Services Federation (WS-Federation) standard enabling federation of identity, attribute, authentication and authorization information can now provide real extended Single Sign On solutions. Various solutions have been investigated at CERN and now, a Web SSO solution using some parts of WS-Federation technology is available. Using the Shibboleth Service Provider module for Apache hosted web sites and Microsoft ADFS as the identity provider linked to Active Directory user, users can now authenticate on any web application using a single authentication platform, providing identity, user information (building, phone...) as well as group membership enabling authorization possibilities. A typical scenario: a CERN user can now authenticate on a Linux/Apache website using Windows Integrated credentials, and his Active Directory group membership can be checked before allowing access to a specific web page
Grover, Saurabh
2015-01-01
This book is aimed at IT admins, consultants, and architects alike who wish to deploy, manage, and maintain Hyper-V solutions in organizations of various sizes. You are expected to have a working knowledge of managing Windows Server and a fair understanding of networking and storage concepts.
Climate Change. Solutions for Australia
Energy Technology Data Exchange (ETDEWEB)
Coleman, T.; Hoegh-Guldberg, O.; Karoly, D.; Lowe, I.; McMichael, T.; Mitchell, C.; Pearman, G.; Scaife, P.; Reynolds, A. (eds.)
2004-06-01
The Australian Climate Group was convened in late 2003 by WWF Australia and the Insurance Australia Group (IAG) in response to the increasing need for action on climate change in Australia. This group proposes a set of solutions to lower the risk that climate change will reach a dangerous level.
Archival storage solutions for PACS
Chunn, Timothy
1997-05-01
While they are many, one of the inhibitors to the wide spread diffusion of PACS systems has been robust, cost effective digital archive storage solutions. Moreover, an automated Nearline solution is key to a central, sharable data repository, enabling many applications such as PACS, telemedicine and teleradiology, and information warehousing and data mining for research such as patient outcome analysis. Selecting the right solution depends on a number of factors: capacity requirements, write and retrieval performance requirements, scaleability in capacity and performance, configuration architecture and flexibility, subsystem availability and reliability, security requirements, system cost, achievable benefits and cost savings, investment protection, strategic fit and more.This paper addresses many of these issues. It compares and positions optical disk and magnetic tape technologies, which are the predominant archive mediums today. Price and performance comparisons will be made at different archive capacities, plus the effect of file size on storage system throughput will be analyzed. The concept of automated migration of images from high performance, high cost storage devices to high capacity, low cost storage devices will be introduced as a viable way to minimize overall storage costs for an archive. The concept of access density will also be introduced and applied to the selection of the most cost effective archive solution.
Solution properties of hydrophobically modified
Directory of Open Access Journals (Sweden)
A.M. Al-Sabagh
2016-12-01
Full Text Available We tested nine hydrophobically modified polyacrylamides with molecular weights situated between 1.58 and 0.89 × 106 g/mol for enhanced oil recovery applications. Their solution properties were investigated in the distilled water, brine solution, formation water and sea water. Their critical association concentrations were determined from the relationship between their concentrations and the corresponding apparent viscosities (ηapp at 30 °C at shear rate 6 s−1. They were between 0.4 and 0.5 g/dl. The brine solutions of 0.5 g/dl of HM-PAMs were investigated at different conditions regarding their apparent viscosities. Such conditions were mono and divalent cations, temperature ranging from 30 to 90 °C, the shear rate ranging from 6 to 30 s−1 and the aging time for 45 days. The surface and interfacial tensions for the HM-PAMs were measured for concentration range from 0.01 to 1 g/dl brine solutions at 30 °C and their emulsification efficiencies were investigated for 7 days. The discrepancy in the properties and efficiencies of the tested copolymers was discussed in the light of their chemical structure.
Solutions of Einstein's field equations
Energy Technology Data Exchange (ETDEWEB)
Tomonaga, Y [Utsunomiya Univ. (Japan). Faculty of Education
1978-12-01
In this paper the author investigates the Einstein's field equations of the non-vacuum case and generalizes the solution of Robertson-Walker by the three dimensional Einstein spaces. In Section 2 the author shortly generalizes the dynamic space-time of G. Lemetre and A. Friedmann by a simple transformation.
Fundamental solutions in piezoelectricity. Penny-shaped crack solution
International Nuclear Information System (INIS)
Dyka, Ewa; Rogowski, Bogdan
2006-01-01
The problem of electroelasticity for piezoelectric materials is considered. For axially symmetric states three potentials are introduced, which determine the displacements, the electric potentials, the stresses, the components of the electric field vector and the electric displacements in a piezoelectric body. These fundamental solutions are utilized to solve the penny-shaped crack problem. Two cases of boundary-value problems are considered, namely the permeable and impermeable crack boundary conditions. Exact solutions are obtained for elastic and electric fields. The main results are the stress intensity factor for singular stress and the electric displacement intensity factor. The numerical results are presented graphically to show the influence of applied mechanical and electrical loading on the analyzed quantities and to clarify the effect of anisotropy of piezoelectric materials. It is show that the influence of anisotropy of the materials on these fields is significant
Compacton solutions and multiple compacton solutions for a continuum Toda lattice model
International Nuclear Information System (INIS)
Fan Xinghua; Tian Lixin
2006-01-01
Some special solutions of the Toda lattice model with a transversal degree of freedom are obtained. With the aid of Mathematica and Wu elimination method, more explicit solitary wave solutions, including compacton solutions, multiple compacton solutions, peakon solutions, as well as periodic solutions are found in this paper
Directory of Open Access Journals (Sweden)
I.L. Animasaun
2017-12-01
Full Text Available Geometrically, the upper pointed surface of an aircraft and bonnet of a car are examples of upper horizontal surfaces of a paraboloid of revolution (uhspr. The motion of these objects strongly depends on the boundary layer that is formed within the immediate space on it. However, each of these surfaces is neither a horizontal/vertical nor cone/wedge and neither a cone nor a wedge. This article presents the motion of 2-dimensional Blasius flow of Carreau fluid on the surface of such object. The case in which the reaction between the Carreau fluid and catalyst at the surface produces significant temperature differences which consequently set up buoyancy-driven flows within the boundary layer is investigated. Single first-order Arrhenius kinetics is adopted to model the reaction on the surface of the catalyst situated on uhspr which initiates the free convection. Suitable similarity variables are applied to non-dimensionalized, parameterized and reduce the governing partial differential equations to a coupled ordinary differential equations (BVP. The BVP is solved numerically using the shooting technique. Temperature distribution in the flow of viscoelastic Carreau fluid is greater than that of a Newtonian fluid. Local heat transfer rate decreases faster when the Carreau fluid is characterized as shear-thinning. Maximum concentration is guaranteed at a small value of power-law index n and large value of thickness parameter. Keywords: Viscoelastic-Carreau fluid, Catalitic surface, Paraboloid of revolution, Numerical method, Uhspr, Boundary layer analysis
Fissile solution dynamics: Student research
Energy Technology Data Exchange (ETDEWEB)
Hetrick, D.L.
1994-09-01
There are two research projects in criticality safety at the University of Arizona: one in dynamic simulation of hypothetical criticality accidents in fissile solutions, and one in criticality benchmarks using transport theory. We have used the data from nuclear excursions in KEWB, CRAC, and SILENE to help in building models for solution excursions. An equation of state for liquids containing gas bubbles has been developed and coupled to point-reactor dynamics in an attempt to predict fission rate, yield, pressure, and kinetic energy. It appears that radiolytic gas is unimportant until after the first peak, but that it does strongly affect the shape of the subsequent power decrease and also the dynamic pressure.
Automatic validation of numerical solutions
DEFF Research Database (Denmark)
Stauning, Ole
1997-01-01
This thesis is concerned with ``Automatic Validation of Numerical Solutions''. The basic theory of interval analysis and self-validating methods is introduced. The mean value enclosure is applied to discrete mappings for obtaining narrow enclosures of the iterates when applying these mappings...... differential equations, but in this thesis, we describe how to use the methods for enclosing iterates of discrete mappings, and then later use them for discretizing solutions of ordinary differential equations. The theory of automatic differentiation is introduced, and three methods for obtaining derivatives...... are described: The forward, the backward, and the Taylor expansion methods. The three methods have been implemented in the C++ program packages FADBAD/TADIFF. Some examples showing how to use the three metho ds are presented. A feature of FADBAD/TADIFF not present in other automatic differentiation packages...
Dynamic viscosity of polymer solutions
Energy Technology Data Exchange (ETDEWEB)
Peterlin, A
1982-03-01
The dynamic viscosity investigation of solutions of long chain polymers in very viscous solvents has definitely shown the existence of the low and high frequency plateau with the gradual transition between them. In both extreme cases the extrapolation of the measured Newtonian viscosities of the plateaus to the infinite dilution yields the limiting intrinsic viscosities. Such a behavior is expected from the dynamic intrinsic viscosity of the necklace model of the linear polymer with finite internal viscosity. The plateau at low frequency shows up in any model of polymer solution. This work shows the constant dynamic intrinsic viscosity in both extreme cases is well reproducible by the necklace model with the internal viscosity acting only between the beads on the same link. 20 references.
Solution assay instrument operations manual
International Nuclear Information System (INIS)
Li, T.K.; Marks, T.; Parker, J.L.
1983-09-01
An at-line solution assay instrument (SAI) has been developed and installed in a plutonium purification and americium recovery process area in the Los Alamos Plutonium Processing Facility. The instrument was designed for accurate, timely, and simultaneous nondestructive analysis of plutonium and americium in process solutions that have a wide range of concentrations and americium/plutonium ratios and for routine operation by process technicians who lack instrumentation background. The SAI, based on transmission-corrected, high-resolution gamma-ray spectroscopy, has two measurement stations attached to a single multichannel analyzer/computer system. To ensure the quality of assay results, the SAI has an internal measurement control program, which requires daily and weekly check runs and monitors key aspects of all assay runs. For a 25-ml sample, the assay precision is 5 g/l within a 2000-s count time
Restoration of uranium solution mining deposits
International Nuclear Information System (INIS)
Devries, F.W.; Lawes, B.C.
1982-01-01
A process is provided for restoring an ore deposit after uranium solution mining using ammonium carbonate leaching solutions has ceased. The process involves flushing the deposit with an aqueous solution of a potassium salt during which potassium ions exchange with ammonium ions remaining in the deposit. The ammonium containing flushing solution is withdrawn from the deposit for disposal
Gold and Silver Extraction from Leach Solutions
Bagdaulet K. Kenzhaliyev; Renata R. Iskhakova; Zamzagul D. Dosymbaeva; Esen N. Sulejmenov
2014-01-01
There has been carried out an investigation on the extraction of gold and silver from thiosulfate solutions: standard test and technological solutions of chemical and electrochemical leaching. The influence of related metals on the process of extracting gold from solution was studied. There has been conducted a comparative study of the IR spectra of solutions after the sorption of gold, silver and related metals.
Restoration of uranium solution mining deposits
Energy Technology Data Exchange (ETDEWEB)
Devries, F.W.; Lawes, B.C.
1982-01-19
A process is provided for restoring an ore deposit after uranium solution mining using ammonium carbonate leaching solutions has ceased. The process involves flushing the deposit with an aqueous solution of a potassium salt during which potassium ions exchange with ammonium ions remaining in the deposit. The ammonium containing flushing solution is withdrawn from the deposit for disposal.
Exact solutions to quadratic gravity
Czech Academy of Sciences Publication Activity Database
Pravda, Vojtěch; Pravdová, Alena; Podolský, J.; Švarc, J.
2017-01-01
Roč. 95, č. 8 (2017), č. článku 084025. ISSN 2470-0010 R&D Projects: GA ČR GB14-37086G Institutional support: RVO:67985840 Keywords : quadratic gravity * exact solutions * Kundt spacetimes Subject RIV: BA - General Mathematics OBOR OECD: Applied mathematics Impact factor: 4.568, year: 2016 https://journals.aps.org/prd/abstract/10.1103/PhysRevD.95.084025
Providing solutions to engineering problems
International Nuclear Information System (INIS)
Connop, R.P.P.
1991-01-01
BNFL has acquired unique experience over a period of 40 years in specifying, designing and constructing spent fuel reprocessing and associated waste management plant. This experience is currently used to support a pound 5.5 billion capital investment programme. This paper reviews a number of engineering problems and their solutions to highlight BNFL experience in providing comprehensive specification, design and engineering and project management services. (author)
New regular black hole solutions
International Nuclear Information System (INIS)
Lemos, Jose P. S.; Zanchin, Vilson T.
2011-01-01
In the present work we consider general relativity coupled to Maxwell's electromagnetism and charged matter. Under the assumption of spherical symmetry, there is a particular class of solutions that correspond to regular charged black holes whose interior region is de Sitter, the exterior region is Reissner-Nordstroem and there is a charged thin-layer in-between the two. The main physical and geometrical properties of such charged regular black holes are analyzed.
ATM security via "Stargate" solution
Hensley, Katrina; Ludden, Fredrick
1999-01-01
Approved for public release, distribution unlimited. In today's world of integrating voice, video and data into a single network, Asynchronous Transfer Mode (ATM) networks have become prevalent in the Department of Defense. The Department of Defense's critical data will have to pass through public networks, which causes concern for security. This study presents an efficient solution aimed at authenticating communications over public ATM networks. The authenticating device, Stargate, utiliz...
Clean Energy Solutions Center (Presentation)
Energy Technology Data Exchange (ETDEWEB)
Reategui, S.
2012-07-01
The Clean Energy Ministerial launched the Clean Energy Solutions Center in April, 2011 for major economy countries, led by Australia and U.S. with other CEM partners. Partnership with UN-Energy is extending scope to support all developing countries: 1. Enhance resources on policies relating to energy access, small to medium enterprises (SMEs), and financing programs; 2. Offer expert policy assistance to all countries; 3. Expand peer to peer learning, training, and deployment and policy data for developing countries.
Combinatorial solutions to integrable hierarchies
Kazarian, M. E.; Lando, S. K.
2015-06-01
This paper reviews modern approaches to the construction of formal solutions to integrable hierarchies of mathematical physics whose coefficients are answers to various enumerative problems. The relationship between these approaches and the combinatorics of symmetric groups and their representations is explained. Applications of the results to the construction of efficient computations in problems related to models of quantum field theories are described. Bibliography: 34 titles.
Exact solutions to quadratic gravity
Czech Academy of Sciences Publication Activity Database
Pravda, Vojtěch; Pravdová, Alena; Podolský, J.; Švarc, J.
2017-01-01
Roč. 95, č. 8 (2017), č. článku 084025. ISSN 2470-0010 R&D Projects: GA ČR GB14-37086G Institutional support: RVO:67985840 Keywords : quadratic gravity * exact solutions * Kundt spacetimes Subject RIV: BA - General Mathematics OBOR OECD: Applied mathematics Impact factor: 4.568, year: 2016 https://journals. aps .org/prd/abstract/10.1103/PhysRevD.95.084025
Solution Prototyping with Design Thinking
DEFF Research Database (Denmark)
Efeoglu, Arkin; Møller, Charles; Serie, Michel
2014-01-01
are tried to be broken and Design Thinking advantages are increasingly preferred by man- agement. This case study based paper provides key insights into how DT phases and behavior can be changed for creating synergy across employees, manage- ment and products from which the end-consumer benefits. The Social...... Media for SAP store case study combines a conceptual and product oriented solution deri- vation with Design Thinking....
Solution Prototyping with Design Thinking
DEFF Research Database (Denmark)
Efeoglu, Arkin; Møller, Charles; Serie, Michel
are tried to be broken and Design Thinking advantages are increasingly preferred by man- agement. This case study based paper provides key insights into how DT phases and behavior can be changed for creating synergy across employees, manage- ment and products from which the end-consumer benefits. The Social...... Media for SAP store case study combines a conceptual and product oriented solution deri- vation with Design Thinking....
Renormgroup symmetry for solution functionals
International Nuclear Information System (INIS)
Shirkov, D.V.; Kovalev, V.F.
2004-01-01
The paper contains generalization of the renormgroup algorithm for boundary value problems of mathematical physics and related concept of the renormgroup symmetry, formulated earlier by the authors with reference to models based on differential equations. These algorithm and symmetry are formulated now for models with nonlocal (integral) equations. We discuss in detail and illustrate by examples the applications of the generalized algorithm to models with nonlocal terms which appear as linear functionals of the solution. (author)
Experimental Designs Exercises and Solutions
Kabe, DG
2007-01-01
This volume provides a collection of exercises together with their solutions in design and analysis of experiments. The theoretical results, essential for understanding, are given first. These exercises have been collected during the authors teaching courses over a long period of time. These are particularly helpful to the students studying the design of experiments and instructors and researchers engaged in the teaching and research of design by experiment.
One Monopole-Antimonopole Pair Solutions
International Nuclear Information System (INIS)
Teh, Rosy; Wong, K.-M.
2009-01-01
We present new classical generalized one monopole-antimonopole pair solutions of the SU(2) Yang-Mills-Higgs theory with the Higgs field in the adjoint representation. We show that in general the one monopole-antimonopole solution need not be solved by imposing mθ-winding number to be integer greater than one. We also show that this solution can be solved when m = 1 by transforming the large distance asymptotic solutions to general solutions that depend on a parameter p. Secondly we show that these large distance asymptotic solutions can be further generalized to the Jacobi elliptic functions. We focus our numerical calculation on the Jacobi elliptic functions solution when the nφ-winding number is one and show that this generalized Jacobi elliptic 1-MAP solution possesses lower energy. All these solutions are numerical finite energy non-BPS solutions of the Yang-Mills-Higgs field theory.
Linear superposition solutions to nonlinear wave equations
International Nuclear Information System (INIS)
Liu Yu
2012-01-01
The solutions to a linear wave equation can satisfy the principle of superposition, i.e., the linear superposition of two or more known solutions is still a solution of the linear wave equation. We show in this article that many nonlinear wave equations possess exact traveling wave solutions involving hyperbolic, triangle, and exponential functions, and the suitable linear combinations of these known solutions can also constitute linear superposition solutions to some nonlinear wave equations with special structural characteristics. The linear superposition solutions to the generalized KdV equation K(2,2,1), the Oliver water wave equation, and the k(n, n) equation are given. The structure characteristic of the nonlinear wave equations having linear superposition solutions is analyzed, and the reason why the solutions with the forms of hyperbolic, triangle, and exponential functions can form the linear superposition solutions is also discussed
Exact Solutions for Two Equation Hierarchies
International Nuclear Information System (INIS)
Song-Lin, Zhao; Da-Jun, Zhang; Jie, Ji
2010-01-01
Bilinear forms and double-Wronskian solutions are given for two hierarchies, the (2+1)-dimensional breaking Ablowitz–Kaup–Newell–Segur (AKNS) hierarchy and the negative order AKNS hierarchy. According to some choices of the coefficient matrix in the Wronskian condition equation set, we obtain some kinds of solutions for these two hierarchies, such as solitons, Jordan block solutions, rational solutions, complexitons and mixed solutions. (general)
International Nuclear Information System (INIS)
Tian Lixin; Yin Jiuli
2004-01-01
In this paper, we introduce the fully nonlinear generalized Camassa-Holm equation C(m,n,p) and by using four direct ansatzs, we obtain abundant solutions: compactons (solutions with the absence of infinite wings), solitary patterns solutions having infinite slopes or cups, solitary waves and singular periodic wave solutions and obtain kink compacton solutions and nonsymmetry compacton solutions. We also study other forms of fully nonlinear generalized Camassa-Holm equation, and their compacton solutions are governed by linear equations
Empirical resistive-force theory for slender biological filaments in shear-thinning fluids
Riley, Emily E.; Lauga, Eric
2017-06-01
Many cells exploit the bending or rotation of flagellar filaments in order to self-propel in viscous fluids. While appropriate theoretical modeling is available to capture flagella locomotion in simple, Newtonian fluids, formidable computations are required to address theoretically their locomotion in complex, nonlinear fluids, e.g., mucus. Based on experimental measurements for the motion of rigid rods in non-Newtonian fluids and on the classical Carreau fluid model, we propose empirical extensions of the classical Newtonian resistive-force theory to model the waving of slender filaments in non-Newtonian fluids. By assuming the flow near the flagellum to be locally Newtonian, we propose a self-consistent way to estimate the typical shear rate in the fluid, which we then use to construct correction factors to the Newtonian local drag coefficients. The resulting non-Newtonian resistive-force theory, while empirical, is consistent with the Newtonian limit, and with the experiments. We then use our models to address waving locomotion in non-Newtonian fluids and show that the resulting swimming speeds are systematically lowered, a result which we are able to capture asymptotically and to interpret physically. An application of the models to recent experimental results on the locomotion of Caenorhabditis elegans in polymeric solutions shows reasonable agreement and thus captures the main physics of swimming in shear-thinning fluids.
Commercial Lighting Solutions Webtool Peer Review Report, Office Solutions
Energy Technology Data Exchange (ETDEWEB)
Beeson, Tracy A.; Jones, Carol C.
2010-02-01
The Commercial Lighting Solutions (CLS) project directly supports the U.S. Department of Energy’s Commercial Building Energy Alliance efforts to design high performance buildings. CLS creates energy efficient best practice lighting designs for widespread use, and they are made available to users via an interactive webtool that both educates and guides the end user through the application of the Lighting Solutions. This report summarizes the peer review of the CLS webtool for offices. The methodology for the peer review process included data collection (stakeholder input), analysis of the comments, and organization of the input into categories for prioritization of the comments against a set of criteria. Based on this process, recommendations were developed for the release of version 2.0 of the webtool at the Lightfair conference in Las Vegas in May 2010. The report provides a list of the top ten most significant and relevant improvements that will be made within the webtool for version 2.0 as well as appendices containing the comments and short-term priorities in additional detail. Peer review comments that are considered high priority by the reviewers and the CLS team but cannot be completed for Version 2.0 are listed as long-term recommendations.
Approximate solutions to Mathieu's equation
Wilkinson, Samuel A.; Vogt, Nicolas; Golubev, Dmitry S.; Cole, Jared H.
2018-06-01
Mathieu's equation has many applications throughout theoretical physics. It is especially important to the theory of Josephson junctions, where it is equivalent to Schrödinger's equation. Mathieu's equation can be easily solved numerically, however there exists no closed-form analytic solution. Here we collect various approximations which appear throughout the physics and mathematics literature and examine their accuracy and regimes of applicability. Particular attention is paid to quantities relevant to the physics of Josephson junctions, but the arguments and notation are kept general so as to be of use to the broader physics community.
Fuel cell vehicles: technological solution
International Nuclear Information System (INIS)
Lopez Martinez, J. M.
2004-01-01
Recently it takes a serious look at fuel cell vehicles, a leading candidate for next-generation vehicle propulsion systems. The green house effect and air quality are pressing to the designers of internal combustion engine vehicles, owing to the manufacturers to find out technological solutions in order to increase the efficiency and reduce emissions from the vehicles. On the other hand, energy source used by currently propulsion systems is not renewable, the well are limited and produce CO 2 as a product from the combustion process. In that situation, why fuel cell is an alternative of internal combustion engine?
Greenhouse effect: there are solutions
International Nuclear Information System (INIS)
Anon.
1997-01-01
A review of solutions that may be undertaken in order to reduce the greenhouse effect gas emissions is presented: clean energy generation through municipal, agricultural and industrial waste processing, reducing energy consumption through public transportation promotion, clean fuel buses and vehicles, or using energy efficient boilers, reduction of carbon dioxide emission from industry through process optimization, waste recycling, energy substitution and conservation, diminution of CO 2 emissions in commercial and residential sectors through space heating and air conditioning retrofitting, lighting substitution. Pollution abatement potentials are evaluated in each case, notably in France
Integrated solution for field operations
Energy Technology Data Exchange (ETDEWEB)
Aubin, Renaud; Dionis, Francois [EDF, Chatou (France)
2014-08-15
This document presents our approach to design and to implement mobile applications for field operations. Internal on-field studies yield to the fact that the value added by mobile solutions is correlated with the easiness of their integration with each other and with the underlying information systems. Moreover, the fast-growing mobile market brings new concepts to the mass and industrial applications design can benefit from these. As a consequence, a simple components-based approach has been applied to design and develop mobile applications for field operations and on-site experiments of the resulting applications have been conducted.
Integrated solution for field operations
International Nuclear Information System (INIS)
Aubin, Renaud; Dionis, Francois
2014-01-01
This document presents our approach to design and to implement mobile applications for field operations. Internal on-field studies yield to the fact that the value added by mobile solutions is correlated with the easiness of their integration with each other and with the underlying information systems. Moreover, the fast-growing mobile market brings new concepts to the mass and industrial applications design can benefit from these. As a consequence, a simple components-based approach has been applied to design and develop mobile applications for field operations and on-site experiments of the resulting applications have been conducted
Silverlight 4 Problem - Design - Solution
Lecrenski, Nick
2010-01-01
A hands-on guide to Microsoft's latest rich application development technology: Silverlight 4. Silverlight 4 is the newest version of the rich Internet application toolkit that provides support for .NET capabilities over the Internet. With this latest release of Silverlight, Microsoft has revolutionized the way that Web applications can be created. This book uses the popular Problem – Design – Solution strategy to demonstrate how to harness the power and abilities of Silverlight 4 to add value to the overall user experience of a Web site. Using a Web site created by the author as a reference p
Symmetries and Dirac equation solutions
International Nuclear Information System (INIS)
Souza, Marcio Lima de.
1991-06-01
The purpose of this thesis is the extension to be relativistic case of a method that has proved useful for the solution of various potential problems in non relativistic situation. This method, the method of dynamical symmetries, is based on the Baker-Campbell-Hausdorf formulae and developed first for the particular example of the relativistic Coulomb problem. Here we generalize the method for a Hamiltonian that can be written as a linear combination of generators of the SO(2,1) group. As illustrative examples, we solve the problem of a charged particle in a constant magnetic field and the exponential magnetic field. (author). 21 refs
Integrated solution for field operations
International Nuclear Information System (INIS)
Aubin, Renaud; Dionis, Francois
2014-01-01
This paper presents the authors' approach to design and to implement mobile applications for field operations. Internal on-field studies can yield the fact that the value-added by mobile solutions is correlated with the easiness of their integration with each other and with the underlying information systems. Moreover, the fast-growing mobile market brings new concepts to the mass and industrial applications design can benefit from these. As a consequence, a simple components-based approach has been applied to design and develop mobile applications for field operations and on-site experiments of the resulting applications have been conducted. (author)
MIGRATION – EFFECTS AND SOLUTIONS
Directory of Open Access Journals (Sweden)
Raluca Cruceru
2012-12-01
Full Text Available There are three main flows that influence workforce performance—worker migration, the dissemination of knowledge, and overseas development assistance. For the present paper we decided to deal with the analyses of these three, yet mainly migration. We considered it to be one of the most important phenomenon existent on the market at this hour and with the highest negative impact on the economic and social situation. We presented a case study regarding the situation of migration in Romania and the main candidates to Romanian intelligence imports, the main issues and possible solutions to the problems encountered.
Transition state structures in solution
International Nuclear Information System (INIS)
Bertran, J.; Lluch, J. M.; Gonzalez-Lafont, A.; Dillet, V.; Perez, V.
1995-01-01
In the present paper the location of transition state structures for reactions in solution has been studied. Continuum model calculations have been carried out on the Friedel-Crafts alkylation reaction and a proton transfer through a water molecule between two oxygen atoms in formic acid. In this model the separation between the chemical system and the solvent has been introduced. On the other hand, the discrete Monte Carlo methodology has also been used to simulate the solvent effect on dissociative electron transfer processes. In this model, the hypothesis of separability is not assumed. Finally, the validity of both approaches is discussed
Lanthanide complexation in aqueous solutions
International Nuclear Information System (INIS)
Choppin, G.R.
1984-01-01
The lanthanide elements form an extended series of cations with the same charge, slightly varying radii and useful magnetic and spectroscopic properties. Their use in technology is growing rapidly as their properties are more fully explored. The lanthanides also offer scientists valuable and often unique probes for investigating a variety of chemical and physical phenomena. This review has attempted to call attention to these latter uses without trying to provide a thorough discussion of all the relevant literature. Hopefully, awareness of the more interesting facets of present studies of lanthanide complexes in aqueous solution will spur even more advances in the use of these elements. (Auth.)
Research on cloud computing solutions
Directory of Open Access Journals (Sweden)
Liudvikas Kaklauskas
2015-07-01
Full Text Available Cloud computing can be defined as a new style of computing in which dynamically scala-ble and often virtualized resources are provided as a services over the Internet. Advantages of the cloud computing technology include cost savings, high availability, and easy scalability. Voas and Zhang adapted six phases of computing paradigms, from dummy termi-nals/mainframes, to PCs, networking computing, to grid and cloud computing. There are four types of cloud computing: public cloud, private cloud, hybrid cloud and community. The most common and well-known deployment model is Public Cloud. A Private Cloud is suited for sensitive data, where the customer is dependent on a certain degree of security.According to the different types of services offered, cloud computing can be considered to consist of three layers (services models: IaaS (infrastructure as a service, PaaS (platform as a service, SaaS (software as a service. Main cloud computing solutions: web applications, data hosting, virtualization, database clusters and terminal services. The advantage of cloud com-puting is the ability to virtualize and share resources among different applications with the objective for better server utilization and without a clustering solution, a service may fail at the moment the server crashes.DOI: 10.15181/csat.v2i2.914
Peritoneal solute transport and inflammation.
Davies, Simon J
2014-12-01
The speed with which small solutes cross the peritoneal membrane, termed peritoneal solute transport rate (PSTR), is a key measure of individual membrane performance. PSTR can be quantified easily by using the 4-hour dialysate to plasma creatinine ratio, which, although only an approximation to the diffusive characteristics of the membrane, has been well validated clinically in terms of its relationship to patient survival and changes in longitudinal membrane function. This has led to changes in peritoneal dialysis modality use and dialysis prescription. An important determinant of PSTR is intraperitoneal inflammation, as exemplified by local interleukin 6 production, which is largely independent of systemic inflammation and its relationship to comorbid conditions and increased mortality. There is no strong evidence to support the contention that the peritoneal membrane in some individuals with high PSTR is qualitatively different at the start of treatment; rather, it represents a spectrum that is determined in part by genetic factors. Both clinical and experimental evidence support the view that persistent intraperitoneal inflammation, detected as a continuously high or increasing PSTR, may predispose the membrane to progressive fibrosis. Copyright © 2014 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.
INTERCULTURAL MISUNDERSTANDINGS: CAUSES AND SOLUTIONS
Directory of Open Access Journals (Sweden)
Майкл Б Хиннер
2017-12-01
Full Text Available Intercultural misunderstandings involve a number of complex causes which can easily escalate into conflicts. Since conflicts are also complex, it is not easy to find solutions because there is no one solution for all problems. Systems Theory, transdisciplinarity, and the social ecological model take a holistic approach in investigating complex phenomena. They permit the creation of a theoretical framework based on previous empirical research and theories across scientific disciplines to identify the relevant elements of complex phenomena and to understand the interrelationship of these elements. Intercultural misunderstandings and conflicts are very complex phenomena because they include culture, perception, identity, ethnocentrism, relationships, trust building and conflict management as well as intercultural commu-nication competence which entails cognition, metacognition, and social metacognition. Since most em-pirical studies focus on isolated, individual elements in specific contexts, this article describes the theoretical framework of how the various findings and theories developed in different scientific disciplines can be used to form a cohesive framework to help circumvent intercultural misunderstandings and conflicts. In so doing, it follows the general principles of Systems Theory, transdisciplinarity, and the social ecological model.
Solute-vacancy binding in aluminum
International Nuclear Information System (INIS)
Wolverton, C.
2007-01-01
Previous efforts to understand solute-vacancy binding in aluminum alloys have been hampered by a scarcity of reliable, quantitative experimental measurements. Here, we report a large database of solute-vacancy binding energies determined from first-principles density functional calculations. The calculated binding energies agree well with accurate measurements where available, and provide an accurate predictor of solute-vacancy binding in other systems. We find: (i) some common solutes in commercial Al alloys (e.g., Cu and Mg) possess either very weak (Cu), or even repulsive (Mg), binding energies. Hence, we assert that some previously reported large binding energies for these solutes are erroneous. (ii) Large binding energies are found for Sn, Cd and In, confirming the proposed mechanism for the reduced natural aging in Al-Cu alloys containing microalloying additions of these solutes. (iii) In addition, we predict that similar reduction in natural aging should occur with additions of Si, Ge and Au. (iv) Even larger binding energies are found for other solutes (e.g., Pb, Bi, Sr, Ba), but these solutes possess essentially no solubility in Al. (v) We have explored the physical effects controlling solute-vacancy binding in Al. We find that there is a strong correlation between binding energy and solute size, with larger solute atoms possessing a stronger binding with vacancies. (vi) Most transition-metal 3d solutes do not bind strongly with vacancies, and some are even energetically strongly repelled from vacancies, particularly for the early 3d solutes, Ti and V
A competitive solution for cooperative truckload delivery
Hezarkhani, B.; Slikker, M.; Woensel, van T.
2016-01-01
This paper introduces a solution for gain sharing in consortia of logistic providers where joint planning of truckload deliveries enables the reduction of empty kilometers. The highly competitive nature of freight transport markets necessitates solutions that distinguish among the logistics
Mean-field learning for satisfactory solutions
Tembine, Hamidou; Tempone, Raul; Vilanova, Pedro
2013-01-01
One of the fundamental challenges in distributed interactive systems is to design efficient, accurate, and fair solutions. In such systems, a satisfactory solution is an innovative approach that aims to provide all players with a satisfactory payoff
Perturbation of an exact strong gravity solution
International Nuclear Information System (INIS)
Baran, S.A.
1982-10-01
Perturbations of an exact strong gravity solution are investigated. It is shown, by using the new multipole expansions previously presented, that this exact and static spherically symmetric solution is stable under odd parity perturbations. (author)
Gold and Silver Extraction from Leach Solutions
Directory of Open Access Journals (Sweden)
Bagdaulet K. Kenzhaliyev
2014-03-01
Full Text Available There has been carried out an investigation on the extraction of gold and silver from thiosulfate solutions: standard test and technological solutions of chemical and electrochemical leaching. The influence of related metals on the process of extracting gold from solution was studied. There has been conducted a comparative study of the IR spectra of solutions after the sorption of gold, silver and related metals.
Engineering report (conceptual design) PFP solution stabilization
Energy Technology Data Exchange (ETDEWEB)
Witt, J.B.
1997-07-17
This Engineering Report (Conceptual Design) addresses remediation of the plutonium-bearing solutions currently in inventory at the Plutonium Finishing Plant (PFP). The recommendation from the Environmental Impact Statement (EIS) is that the solutions be treated thermally and stabilized as a solid for long term storage. For solutions which are not discardable, the baseline plan is to utilize a denitration process to stabilize the solutions prior to packaging for storage.
Engineering report (conceptual design) PFP solution stabilization
International Nuclear Information System (INIS)
Witt, J.B.
1997-01-01
This Engineering Report (Conceptual Design) addresses remediation of the plutonium-bearing solutions currently in inventory at the Plutonium Finishing Plant (PFP). The recommendation from the Environmental Impact Statement (EIS) is that the solutions be treated thermally and stabilized as a solid for long term storage. For solutions which are not discardable, the baseline plan is to utilize a denitration process to stabilize the solutions prior to packaging for storage
Exact solutions and singularities in string theory
International Nuclear Information System (INIS)
Horowitz, G.T.; Tseytlin, A.A.
1994-01-01
We construct two new classes of exact solutions to string theory which are not of the standard plane wave of gauged WZW type. Many of these solutions have curvature singularities. The first class includes the fundamental string solution, for which the string coupling vanishes near the singularity. This suggests that the singularity may not be removed by quantum corrections. The second class consists of hybrids of plane wave and gauged WZW solutions. We discuss a four-dimensional example in detail
On polynomial solutions of the Heun equation
International Nuclear Information System (INIS)
Gurappa, N; Panigrahi, Prasanta K
2004-01-01
By making use of a recently developed method to solve linear differential equations of arbitrary order, we find a wide class of polynomial solutions to the Heun equation. We construct the series solution to the Heun equation before identifying the polynomial solutions. The Heun equation extended by the addition of a term, -σ/x, is also amenable for polynomial solutions. (letter to the editor)
Mobility needs and wireless solutions
DEFF Research Database (Denmark)
Saugstrup, Dan; Henten, Anders
The main purpose of this report is to spell out a methodological approach to the analysis of user needs with respect to mobility. Furthermore, this methodological approach is used in an exemplary analysis of the relationship between user needs and technology solutions offered by different wireless...... technologies. The report is based on a research approach, emphasizing important aspects in relation to developing more user oriented mobile services and applications in a heterogeneous network environment. As a staring point, Scandinavian research within the field of social science concerning mobility...... is described and discussed. Furthermore different wireless technologies are briefly described and discussed in relation to possible transmission capacities and coverage areas. In addition to this, a preliminary framework regarding the implications of mobility on the use and development of mobile services...
Multivariate statistics exercises and solutions
Härdle, Wolfgang Karl
2015-01-01
The authors present tools and concepts of multivariate data analysis by means of exercises and their solutions. The first part is devoted to graphical techniques. The second part deals with multivariate random variables and presents the derivation of estimators and tests for various practical situations. The last part introduces a wide variety of exercises in applied multivariate data analysis. The book demonstrates the application of simple calculus and basic multivariate methods in real life situations. It contains altogether more than 250 solved exercises which can assist a university teacher in setting up a modern multivariate analysis course. All computer-based exercises are available in the R language. All R codes and data sets may be downloaded via the quantlet download center www.quantlet.org or via the Springer webpage. For interactive display of low-dimensional projections of a multivariate data set, we recommend GGobi.
Solution synthesis of germanium nanocrystals
Gerung, Henry [Albuquerque, NM; Boyle, Timothy J [Kensington, MD; Bunge, Scott D [Cuyahoga Falls, OH
2009-09-22
A method for providing a route for the synthesis of a Ge(0) nanometer-sized material from. A Ge(II) precursor is dissolved in a ligand heated to a temperature, generally between approximately 100.degree. C. and 400.degree. C., sufficient to thermally reduce the Ge(II) to Ge(0), where the ligand is a compound that can bond to the surface of the germanium nanomaterials to subsequently prevent agglomeration of the nanomaterials. The ligand encapsulates the surface of the Ge(0) material to prevent agglomeration. The resulting solution is cooled for handling, with the cooling characteristics useful in controlling the size and size distribution of the Ge(0) materials. The characteristics of the Ge(II) precursor determine whether the Ge(0) materials that result will be nanocrystals or nanowires.
A solution to nonlinearity problems
International Nuclear Information System (INIS)
Neuffer, D.V.
1989-01-01
New methods of correcting dynamic nonlinearities resulting from the multipole content of a synchrotron or transport line are presented. In a simplest form, correction elements are places at the center (C) of the accelerator half-cells as well as near the focusing (F) and defocusing (D) quadrupoles. In a first approximation, the corrector strengths follow Simpson's Rule, forming an accurate quasi-local canceling approximation to the nonlinearity. The F, C, and D correctors may also be used to obtain precise control of the horizontal, coupled, and vertical motion. Correction by three or more orders of magnitude can be obtained, and simple solutions to a fundamental problem in beam transport have been obtained. 13 refs., 1 fig., 1 tab
Pure energy solutions - pure tomorrows
International Nuclear Information System (INIS)
Allison, J.
2006-01-01
HTC is an energy technology company whose mandate is to deliver 'Carbon Clear Solutions' to address the pending challenges the energy sector is facing in meeting the environmental impact of Greenhouse Gas emissions, and energy security. HTC will speak on its comprehensive suite of technologies including hydrogen production, CO 2 capture and CO 2 sequestration. HTC has patented technologies that produce H 2 from a broad variety of feedstocks such as Natural gas, Diesel, Gasoline, Bio-fuels i.e. ethanol, methanol and Coal Gasification. HTC Hydrogen reformation systems are unique in their method of delivering pure Hydrogen. Dry Reformation Reactor - New catalyst system designed to eliminate contamination problems (i.e. coking) while at the same time operate at a low temperature. Water Gas Shift Reactor - Plus - improved and redesigned catalyst that improves operating temperature and hydrogen production efficiency. Two stage catalyst reactor that provides near balance of the endothermic and exothermic reaction temperatures for efficient energy balance
Regional Transmission Projects: Finding Solutions
Energy Technology Data Exchange (ETDEWEB)
The Keystone Center
2005-06-15
The Keystone Center convened and facilitated a year-long Dialogue on "Regional Transmission Projects: Finding Solutions" to develop recommendations that will help address the difficult and contentious issues related to expansions of regional electric transmission systems that are needed for reliable and economic transmission of power within and across regions. This effort brought together a cross-section of affected stakeholders and thought leaders to address the problem with the collective wisdom of their experience and interests. Transmission owners sat at the table with consumer advocates and environmental organizations. Representatives from regional transmission organizations exchanged ideas with state and federal regulators. Generation developers explored common interests with public power suppliers. Together, the Dialogue participants developed consensus solutions about how to begin unraveling some of the more intractable issues surrounding identification of need, allocation of costs, and reaching consensus on siting issues that can frustrate the development of regional transmission infrastructure. The recommendations fall into three broad categories: 1. Recommendations on appropriate institutional arrangements and processes for achieving regional consensus on the need for new or expanded transmission infrastructure 2. Recommendations on the process for siting of transmission lines 3. Recommendations on the tools needed to support regional planning, cost allocation, and siting efforts. List of Dialogue participants: List of Dialogue Participants: American Electric Power American Transmission Company American Wind Energy Association California ISO Calpine Corporation Cinergy Edison Electric Institute Environmental Defense Federal Energy Regulatory Commission Great River Energy International Transmission Company ISO-New England Iowa Public Utility Board Kanner & Associates Midwest ISO National Association of Regulatory Utility Commissioners National Association
New interior solution describing relativistic fluid sphere
Indian Academy of Sciences (India)
Anewexact solution of embedding class I is presented for a relativistic anisotropicmassive fluid sphere. The new exact solution satisfies Karmarkar condition, is well-behaved in all respects, and therefore is suitable for the modelling of superdense stars. Consequently, using this solution, we have studied in detail two ...
Extremal black holes as exact string solutions
International Nuclear Information System (INIS)
Horowitz, G.T.; Tseytlin, A.A.
1994-01-01
We show that the leading order solution describing an extremal electrically charged black hole in string theory is, in fact, an exact solution to all orders in α' when interpreted in a Kaluza-Klein fashion. This follows from the observation that it can be obtained via dimensional reduction from a five-dimensional background which is proved to be an exact string solution
Homoclinic solutions for Davey-Stewartson equation
International Nuclear Information System (INIS)
Huang Jian; Dai Zhengde
2008-01-01
In this paper, we firstly prove the existence of homoclinic solutions for Davey-Stewartson I equation (DSI) with the periodic boundary condition. Then we obtain a set of exact homoclinic solutions by the novel method-Hirota's method. Moreover, the structure of homoclinic solutions has been investigated. At the same time, we give some numerical simulations which validate these theoretical results
Special solutions of neutral functional differential equations
Directory of Open Access Journals (Sweden)
Győri István
2001-01-01
Full Text Available For a system of nonlinear neutral functional differential equations we prove the existence of an -parameter family of "special solutions" which characterize the asymptotic behavior of all solutions at infinity. For retarded functional differential equations the special solutions used in this paper were introduced by Ryabov.
Requirements elicitation for geo-information solutions
Robbi Sluter, Claudia; van Elzakker, Corné P.J.M.; Ivanova, Ivana
2017-01-01
Geo-information solutions can achieve a higher level of quality if they are developed in accordance with a user-centred design that requires definition of the user requirements in the first step of solution construction. We treat a geo-information solution as a system designed to support human-based
Exact solution of super Liouville model
International Nuclear Information System (INIS)
Yang Zhanying; Zhao Liu; Zhen Yi
2000-01-01
Using Leznov-Saveliev algebraic analysis and Drinfeld-Sokolov construction, the authors obtained the explicit solutions to the super Liouville system in super covariant form and component form. The explicit solution in component form reduces naturally into the Egnchi-Hanson instanton solution of the usual Liouville equation if all the Grassmann odd components are set equal to zero
The stability of the strong gravity solution
International Nuclear Information System (INIS)
Baran, S.A.
1978-01-01
The perturbation of the classical solution to a strong gravity model given by Salam and Strathdee is investigated. Using the Hamiltonian formalism it is shown that this static and spherically symmetric solution is stable under the odd parity perturbations provided some parameters in the solution are suitably restricted
21 CFR 522.900 - Euthanasia solution.
2010-04-01
... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Euthanasia solution. 522.900 Section 522.900 Food... Euthanasia solution. (a) Specifications. Each milliliter (mL) of solution contains: (1) 390 milligrams (mg.... For humane, painless, and rapid euthanasia. (2) Amount. One mL per 10 pounds of body weight. (3...
Unique specification of Yang-Mills solutions
International Nuclear Information System (INIS)
Campbell, W.B.; Joseph, D.W.; Morgan, T.A.
1980-01-01
Screened time-independent cylindrically-symmetric solutions of Yang-Mills equations are given which show that the source does not uniquely determine the field. However, these particular solutions suggest a natural way of uniquely specifying solutions in terms of a physical realization of a symmetry group. (orig.)
Electrochemical regeneration of chrome etching solution
Andel, van Y.; Janssen, L.J.J.
2002-01-01
A metal surface is chromatized with a chromic acid solution to obtain a good adherence of polymer coatings. In this process Cr(VI) is reduced to Cr(III). The oxidation strength of the solution decreases during use. The chrome solution needs to be regenerated and purified. A new anode material,
Classical solutions in lattice gauge theories
International Nuclear Information System (INIS)
Mitrjushkin, V.K.
1996-08-01
The solutions of the classical equations of motion on a periodic lattice are found which correspond to abelian single and double Dirac sheets. These solutions exist also in non-abelian theories. Possible applications of these solutions to the calculation of gauge dependent and gauge invariant observables are discussed. (orig.)
Axisymmetric solution with charge in general relativity
International Nuclear Information System (INIS)
Arutyunyan, G.G.; Papoyan, V.V.
1989-01-01
The possibility of generating solutions to the equations of general relativity from known solutions of the generalized theory of gravitation and vice versa is proved. An electrovac solution to Einstein's equations that describes a static axisymmetric gravitational field is found. 14 refs
Clean Energy Solutions Center Services (Fact Sheet)
Energy Technology Data Exchange (ETDEWEB)
2014-04-01
The Clean Energy Solutions Center (Solutions Center) helps governments, advisors and analysts create policies and programs that advance the deployment of clean energy technologies. The Solutions Center partners with international organizations to provide online training, expert assistance, and technical resources on clean energy policy.
Hyperscaling violating solutions in generalised EMD theory
Directory of Open Access Journals (Sweden)
Li Li
2017-04-01
Full Text Available This short note is devoted to deriving scaling but hyperscaling violating solutions in a generalised Einstein–Maxwell-Dilaton theory with an arbitrary number of scalars and vectors. We obtain analytic solutions in some special case and discuss the physical constraints on the allowed parameter range in order to have a well-defined holographic ground-state solution.
Hyperscaling violating solutions in generalised EMD theory
Energy Technology Data Exchange (ETDEWEB)
Li, Li, E-mail: lil416@lehigh.edu [Crete Center for Theoretical Physics, Institute for Theoretical and Computational Physics, Department of Physics, University of Crete, 71003 Heraklion (Greece); Crete Center for Quantum Complexity and Nanotechnology, Department of Physics, University of Crete, 71003 Heraklion (Greece); Department of Physics, Lehigh University, Bethlehem, PA, 18018 (United States)
2017-04-10
This short note is devoted to deriving scaling but hyperscaling violating solutions in a generalised Einstein–Maxwell-Dilaton theory with an arbitrary number of scalars and vectors. We obtain analytic solutions in some special case and discuss the physical constraints on the allowed parameter range in order to have a well-defined holographic ground-state solution.
Thermodynamic stability of radioactivity standard solutions
International Nuclear Information System (INIS)
Iroulard, M.G.
2007-04-01
The basic requirement when preparing radioactivity standard solutions is to guarantee the concentration of a radionuclide or a radioelement, expressed in the form of activity concentration (Ac = A/m (Bq/g), with A: activity and m: mass of solution). Knowledge of the law of radioactive decay and the half-life of a radionuclide or radioelement makes it possible to determine the activity concentration at any time, and this must be confirmed subsequently by measurement. Furthermore, when radioactivity standard solutions are prepared, it is necessary to establish optimal conditions of thermodynamic stability of the standard solutions. Radioactivity standard solutions are prepared by metrology laboratories from original solutions obtained from a range of suppliers. These radioactivity standard solutions must enable preparation of liquid and/or solid radioactivity standard sources of which measurement by different methods can determine, at a given instant, the activity concentration of the radionuclide or radioelement present in the solution. There are a number of constraints associated with the preparation of such sources. Here only those that relate to the physical and chemical properties of the standard solution are considered, and therefore need to be taken into account when preparing a radioactivity standard solution. These issues are considered in this document in accordance with the following plan: - A first part devoted to the chemical properties of the solutions: - the solubilization media: ultra-pure water and acid media, - the carriers: concentration, oxidation state of the radioactive element and the carrier element. - A second part describing the methodology of the preparation, packaging and storage of standard solutions: - glass ampoules: the structure of glasses, the mechanisms of their dissolution, the sorption phenomenon at the solid-solution interface, - quartz ampoules, - cleaning and packaging: cleaning solutions, internal surface coatings and
Thermodynamic stability of radioactivity standard solutions
Energy Technology Data Exchange (ETDEWEB)
Iroulard, M.G
2007-04-15
The basic requirement when preparing radioactivity standard solutions is to guarantee the concentration of a radionuclide or a radioelement, expressed in the form of activity concentration (Ac = A/m (Bq/g), with A: activity and m: mass of solution). Knowledge of the law of radioactive decay and the half-life of a radionuclide or radioelement makes it possible to determine the activity concentration at any time, and this must be confirmed subsequently by measurement. Furthermore, when radioactivity standard solutions are prepared, it is necessary to establish optimal conditions of thermodynamic stability of the standard solutions. Radioactivity standard solutions are prepared by metrology laboratories from original solutions obtained from a range of suppliers. These radioactivity standard solutions must enable preparation of liquid and/or solid radioactivity standard sources of which measurement by different methods can determine, at a given instant, the activity concentration of the radionuclide or radioelement present in the solution. There are a number of constraints associated with the preparation of such sources. Here only those that relate to the physical and chemical properties of the standard solution are considered, and therefore need to be taken into account when preparing a radioactivity standard solution. These issues are considered in this document in accordance with the following plan: - A first part devoted to the chemical properties of the solutions: - the solubilization media: ultra-pure water and acid media, - the carriers: concentration, oxidation state of the radioactive element and the carrier element. - A second part describing the methodology of the preparation, packaging and storage of standard solutions: - glass ampoules: the structure of glasses, the mechanisms of their dissolution, the sorption phenomenon at the solid-solution interface, - quartz ampoules, - cleaning and packaging: cleaning solutions, internal surface coatings and
Stability studies of oxytetracycline in methanol solution
Wang, Wei; Wu, Nan; Yang, Jinghui; Zeng, Ming; Xu, Chenshan; Li, Lun; Zhang, Meng; Li, Liting
2018-02-01
As one kind of typical tetracycline antibiotics, antibiotic residues of oxytetracycline have been frequently detected in many environmental media. In this study, the stability of oxytetracycline in methanol solution was investigated by high-performance liquid chromatography combined with UV-vis (HPLC-UV). The results show that the stability of oxytetracycline in methanol solution is highly related to its initial concentration and the preserved temperature. Under low temperature condition, the solution was more stable than under room temperature preservation. Under the same temperature preservation condition, high concentrations of stock solutions are more stable than low concentrations. The study provides a foundation for preserving the oxytetracycline-methanol solution.
Solution Focused Approach and Usage of Nursing
Directory of Open Access Journals (Sweden)
Nurcan AKGUL GUNDOGDU
2016-12-01
Full Text Available "Problem talk creates problems; solution talk creates solutions " Steve de Shazer In recent years, concern for solution-oriented approach has increased in nursing practice. In this review it is aimed to give information about nursing application of solution-oriented approach whose efficacy has been proved with many studies. In addition, solution-oriented approach is what how it turned out, the answer to the question of principle, and that is what the management strategy and what the nursing relationship will be sought. [JCBPR 2016; 5(3.000: 145-152
Pollution! Find a STEM solution!
Takač, Danijela; Moćan, Marina
2016-04-01
Primary and secondary school Pantovčak is an innovative school in downtown Zagreb, Croatia. The school is involved in many projects concerning STEM education. Pollution! Find a STEM solution! is a two year long cross-curricular project that grew out of identified need to develop STEM and ICT skills more. Pisa results make evident that students' knowledge is poor and motivation for math and similar subjects is low. Implying priorities of European Commission, like e-learning, raises motivation and also develops basic skills and improves knowledge in science, math, physic, ICT. Main objectives are to increase students' interest in STEM education and careers and introduce them to all available new trends in technology, engineering and science in their region by visiting clean technology industries and strengthening links with them, to introduce some future digital jobs and prepare students for rapid technological changes by integrating ICT into classroom practice more, to highlight the importance of global environmental issues and improve the knowledge in the areas of sustainable development and renewable energy, to develop collaborative partnership between schools and the wider community in formal, non-formal and informal learning, to support multilingualism by publishing Open Educational Resources in 8 different languages and to strengthen the professional profile of the teaching profession. The project brings together 231 teachers and 2729 students from five different European countries in learning to think globally and work on activities that contribute to the community's well-being. There are altogether 33 activities, divided in 4 categories. STEM activities are focused on students building the devices for measuring air, light and noise pollution in their school and homes. They use the scientific method to analyze the data and compare the results with their peers to find a solution. Eskills, digital literacy and digital jobs are focused on introducing career