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Öğe Determination of the particle capture radius in magnetic filters with velocity distribution profile in pores(Taylor & Francis Inc, 2002) Abbasov, T; Altunbas, ASThe determination of the liquid velocity profile in packed bed pores is a well-known problem in the practical applications and the theory of filtration and separation processes. Because the pore sizes are very small, the measurement of the liquid velocity in these areas is very difficult or impossible. By using the modified Kuwabara-Happel cell model, the liquid velocity profile in the pores of packed bed consisting of solid spheres and cylindrical wires was determined. The variation of the liquid velocity with the packed bed porosity and pore geometry has been investigated. By using these results, the expressions for drag force affecting the small particles in the pores and particle capture radius in magnetic filter have been obtained. The effect of the variation of some parameters of filtration system on the particle capture radius has been investigated. Comparisons of the theoretical and experimental results were found to be in good agreement.Öğe Effect of operating parameters on magnetic filtration processes(Amer Chemical Soc, 2004) Künkül, A; Ekmekyapar, A; Akmil, C; Abbasov, TThe effect of operating parameters and the effect of the pH of the liquids to be cleaned on the magnetic filter performance in the filtration processes were investigated. The pH of aqueous suspensions containing ferromagnetic particulates was changed in the range of 3-10. The suspensions were prepared in our laboratory. The effect of the size of filter matrix elements (diameter of the ferromagnetic spheres) and filtration velocity on the filter performance was determined. The filter performance of the filter matrix composed of a mixture of different size spheres was also investigated. A magnetic filter performance above 60% was obtained with a filtration velocity of 0.07 m/s. It was observed that if the size of particles and the fraction of ferromagnetic particles in the suspension are varied in a short range, the effect of the initial concentration of corrosion products on the magnetic filter performance is negligible. The experimental results were compared with theoretical calculations and the data in the literature. Suggestions are given about choosing optimum values of the operating parameters for effective filtration of industrial fluids in magnetic filters.Öğe Estimation of optimum fluid velocity in high gradient magnetic filtration(Taylor & Francis Inc, 1998) Abbasov, T; Ceylan, KA high gradient magnetic cleaning process is favored by several branches of industry for the high purification of various technological fluids involving magnetic(ferro, para, or diamagnetic) particles. This paper presents a theoretical study about the effects of the parameters of a magnetic filtration system on the fluid velocity to be chosen. A model is presented to estimate the optimum filtration velocity needed to satisfy a predefined filter performance. The model is applicable for magnetic filter systems with packing fractions of up to 0.62 and for fluids containing magnetic particles. It is essentially based on the balance of moments acting on particles captured and accumulated in the magnetic filter. The boundary layer approach is used in the development of the model. The results indicate that the optimum filtration velocity depends on the properties of the fluid and on the parameters of the filter system. Model predictions and experimental data given in the literature are in a good agreement.Öğe Filter performance and velocity distribution relation in magnetic filtration of non-Newtonian liquids(Marcel Dekker Inc, 1999) Abbasov, T; Ceylan, KFluid flow regime and the velocity distribution are effective parameters for systems in which various transport phenomena take place. Besides the properties of the contaminating particles and filter system in the case of high gradient magnetic filtration, the theological properties of the fluid are also important for both design and efficiency of the process. This paper presents a theoretical study about estimation of the velocity distribution in a magnetic filter and the dependence of filter performance on this distribution. A model is presented to estimate the velocity distribution and filter performance in magnetic filtration of Newtonian or weak non-Newtonian liquids. The model is essentially based on the balance of forces acting on particles captured and accumulated in the filter. Model predictions and experimental data given in the literature for Newtonian liquids are in a good agreement.Öğe Filtration model of high gradient magnetic filters with granular matrix(Elsevier Science Sa, 1999) Herdem, S; Abbasov, T; Köksal, MConsidering the flow regime of the fluid through the pores of a magnetic filter having a granular matrix composed of ferromagnetic spheres and the accumulation process of the captured particles. the filtration mechanism is investigated. The effect of the different parameters of the filtration system on the efficiency of the magnetic filter is identified. New mathematical expressions are obtained to explain some events which take place in the filtration mechanism and which have not been described completely in the literature so far. The efficiency of the magnetic filter is expressed in terms of the ratios of the magnetic and static pressures which can be measured or identified easily. The theoretical results are compared with the experimental data and it is concluded that they are in good agreement. (C) 1999 Elsevier Science S.A. All rights reserved.Öğe The investigation of the transient regimes in the nonlinear systems by the generalized classical method(Hindawi Publishing Corporation, 2005) Abbasov, T; Bahadir, ARThis paper presents the use of the generalized classical method (GCM) for solving linear and nonlinear differential equations. This method is based on the differential transformation (DT) technique. In the GCM, the solution of the nonlinear transient regimes in the physical processes can be written as a functional series with unknown coefficients. The series can be chosen to satisfy the initial and boundary conditions which represent the properties of the physical process. The unknown coefficients of the series are determined from the differential transformation of the nonlinear differential equation of the system. Therefore, the approximate solution of the nonlinear differential equation can be obtained as a closed-form series. The validity and efficiency of the GCM is shown using some transient regime problems in the electromechanics processes. The numerical results obtained by the present method are compared with the analytical solutions of the equations. It is shown that the results are found to be in good agreement with each other.Öğe Investigations on high gradient magnetic separation processes in rheological media(A A Balkema Publishers, 2000) Sarikaya, M; Erdemoglu, M; Abbasov, TOne of the problems encountered during the separation of suspensions which have various physical and chemical properties in High Gradient Magnetic Separators (HGMS) is the difference of their rheological properties. In the theory and practice of high gradient magnetic separation, the results obtained by the investigation of this problem are seldom and not enough. On the other hand, rheological properties of suspensions used in separation processes affect the efficiency of magnetic separation. Therefore, in order to get automation, improve the control of separation processes and determine the technological and economical parameters of the magnetic separators, it is necessary to take into consideration the rheological properties of the separated mediums. In this paper, by considering the rheological properties of suspensions, the investigation of the trajectory modelling of the particles in the magnetic separators has been presented. Ferromagnetic wires were used as matrix elements. In order to calculate the efficiency of the separator, analytical expressions were obtained by means of the fact that magnetic particles are collected on a magnetised wire. An integral expression of overall separator efficiency was determined by explaining the movement of a particle on a single magnetised wire. The obtained results have been illustrated by using appropriate graphics.Öğe Mathematical modeling of the magnetic filtration processes(Ios Press, 2003) Köksal, M; Abbasov, T; Herdem, SA mathematical model is proposed for the determination of non-stationary characteristics of the cleaning process of industrial liquids in magnetic filters. The theoretical investigation which provides the determination of the variation of the captured particles both with time and along the filter matrix is based on the general filtration equations. Considering the properties of the magnetic filtration process, non-stationary filtration equations involve the capturing and detachment coefficients of the particles in the filter matrix. The effect of the filter length on the magnetic filter performance is also presented. The obtained expressions make possible to compare the experimental and the expected theoretical results.Öğe Model for predicting filtration efficiency and pressure drop in axial magnetic filters(Taylor & Francis Inc, 2000) Herdem, S; Köksal, M; Abbasov, TThe theory of filtration efficiency and filter impedance in axially ordered magnetic filters in conditions of laminar flow is described. The now profile of the suspension that flows axially along the longitudinally ordered wires is determined by the Kuwabara-Happel cell model. Expressions for both filter impedance and filtration efficiency are obtained. In general, they are different from those predicted by previous filtration theories in ideal flow conditions. The derived theoretical formulas are simplified so they can be used easily in engineering applications. The results are compared with the experimental ones presented in the literature, and it is seen that they are consistent with each other.Öğe Modelling of distributed parameter nonlinear systems by differential Taylor method(Polish Acad Sciences Systems Research Inst, 1999) Abbasov, T; Herdem, S; Köksal, MModelling, solution, control and even design of many ecological and engineering systems involve dealing with nonlinear partial differential equations of which analytic solutions are rarely available and numerical approach with or without linearization, or approximation is inevitable most of the time. ill this paper the possibility of analysing such systems by using a fairly new method known as Differential Taylor (DT) Transform and its advantages are proved. The results obtained by this method are compared with the experimental results and shown to be within good agreement with them. It is emphasised that DT Transform is not effective for only filtration systems, but can also be used equally well for absorption, heat and mass transfer, convective diffusion and similar systems.Öğe Modelling of the buildup process of particles in pores of high-gradient magnetic filters using the Fokker-Planck education(Iop Publishing Ltd, 1999) Herdem, S; Abbasov, T; Köksal, MThe stochastic model of the accumulation of particles in a filter matrix composed of magnetized ferromagnetic spheres is considered. The distribution function, which gives the time dependence of the saturation radius that is characterized by both the capturing and detachment events occurring in the capture region, is determined. Taking into account the motional properties of the particles in the capture region, the distribution is evaluated from the solution of the Fokker-Planck equation. The results obtained are compared with, and shown to be similar to, the results of the other methods and some experiments reported in the literature.Öğe A numerical investigation of the liquid flow velocity over an infinity plate which is taking place in a magnetic field(Ios Press, 2005) Bahadir, AR; Abbasov, TIn this paper the change of the magnetchydrodynamic flow velocity of the infinite plate in the non stationary motion of the incompressible viscous liquid has been studied numerically. Outer magnetic field has been directed perpendicular to the plate and assumed moving with the plate. For the different dynamical motion of the plate, the evolution of the velocity has been investigated numerically. The magnetic field induction and the changing of the parameters of the dynamical system on a large range effect to the velocity has been investigated. At a specific point increasing of the magnetic field induction causes decreasing in the velocity. By the increasing the parameters of the manyetohydrodinamic system, the problem becomes more difficult to solve analytically. Therefore, a numerical solution technique is resorted to solve the problem approximately.Öğe Particle capture in axial magnetic filters with power law flow model(Iop Publishing Ltd, 1999) Abbasov, T; Herdem, S; Köksal, MA theory of capture of magnetic particle carried by laminar flow of viscous non-Newtonian (power law) fluid in axially ordered filters is presented. The velocity profile of the fluid flow is determined by the Kuwabara-Happel cell model. For the trajectory of the particle, the capture area and the filter performance simple analytical expressions are obtained. These expressions are valid for particle capture processes from both Newtonian and non-Newtonian fluids. For this reason the obtained theoretical results make it possible to widen the application of high-gradient magnetic filtration (HGMF) to other industrial areas. For Newtonian fluids the theoretical results are shown to be in good agreement with the experimental ones reported in the literature.Öğe Performance of high gradient magnetic filters with granular matrix(Marcel Dekker Inc, 1999) Abbasov, T; Herdem, S; Köksal, MThe performance characteristics of high gradient magnetic filters composed of spherical ferromagnetic granules are determined in terms of dimensionless parameters for a wide range of system parameters. The results obtained are used to overcome some contradictions seen in the literature related to magnetic filters. They are in a good agreement with the experimental data given in the literature for the filters used in laboratories and industry.Öğe Removal of corrosion products from viscous aqueous suspensions by magnetic filtration(Elsevier Science Sa, 2004) Künkül, A; Abbasov, TThe removal of micron-sized corrosion products, which may occur during industrial processing by magnetic filtration, has been theoretically and experimentally investigated. The effect of alterations in theological properties of suspensions carrying particles on magnetic filter performance was determined. Magnetic filter dimensions were 0.03x0.04x0.09 in. The filter was filled with 6.35 X 10(-3) in diameter ferromagnetic spheres. Magnetic fields ranging from B=0 to B=1.4 T perpendicular to the flow direction were applied. The suspension flow rate through the magnetic filter was 0.4 m/s. It was determined that 85% of corrosion products show magnetic properties. The magnetic filtration of suspensions composed of water, corrosion products and glycerine at different concentrations was studied. The effects of initial concentration of corrosion products, viscosity of aqueous suspension, magnetic field intensity and the number of filtration cycles on magnetic filter performance were determined. Theoretical and experimental results were in good agreement. (C) 2004 Elsevier B.V. All rights reserved.Öğe Simulation of the magnetic filtration process of technological liquids and gases by a nonlinear electrical circuit(Iop Publishing Ltd, 2001) Herdem, S; Köksal, M; Abbasov, TA general model that explains the mechanisms of the cleaning process of technological liquids and gases, and that estimates and controls the results of these processes, has not yet been found. It is possible to simulate the magnetic filtration of a technological medium by using electrical circuit theory. Characteristics of filtration processes under different regimes can be easily obtained by an appropriate change of nonlinearity parameters of the circuit, Furthermore, the presented model seems to be promising for non-magnetic filtration and other processes similar to filtration, such as separation, absorption, flotation and classification.Öğe Some aspects of magnetic filtration theory for removal of fine particles from aqueous suspensions(Taylor & Francis Inc, 2006) Sarikaya, M; Abbasov, T; Erdemoglu, MThe magnetic filtration theory was evaluated to intensify the filtration of industrial fluids by magnetic filters. Effects of filtration velocity and external magnetic field intensity on filter performance were investigated and the dependence of the logarithmic efficiency coefficient on filtration velocity was questioned. It was concluded that change in the magnetic susceptibility of the dispersion particles, caused by external magnetic field, and change in the flow rate properties of the liquid alongside the filter pores are the most essential factors to be considered in the design, development, and modeling of magnetic filtration systems in various industrial areas.Öğe Theoretical interpretation of the filtration process in magnetized packed beds(Elsevier Science Sa, 2001) Abbasov, TThe purity of industrial liquids and gases is effected by particles having micron and submicron sizes. Many of the particles in those streams are ferro- or paramagnetic substances. Because of the low concentration of these particles, classical filters (mechanical, separator, etc.) do not perform significant filtration process, and magnetic filters (MFs) which have magnetized packed bed show greater capacity of capturing these particles. Also, MFs show different properties of non-stationary performance characteristics compared to the other type filters. The variation of the MF performance with time is initially constant for some period of the filtration process but falls after that filtration time. A magnetic filtration equation which takes these properties into account has been developed. This equation includes magnetic, hydrodynamic and geometric parameters of the filtration system. The equation obtained is a linear partial-differential equation, which must be solved analytically. The theoretical results obtained from the analytical solution have been compared with the experimental results obtained from various industrial areas using MFs. It can be concluded that a good agreement was found. (C) 2001 Elsevier Science B.V. All rights reserved.Öğe A theoretical model for estimation of drag force in the flow of non-newtonian fluids around spherical solid particles(Elsevier Science Sa, 1999) Ceylan, K; Herdem, S; Abbasov, TA theoretical approach for estimation of the drag correlation coefficients in the flow of Newtonian or weak non-Newtonian liquids around spherical solid particles is presented. Some new analytical relations are derived by using a stream function and the energy dissipation equation to approximate the drag coefficients to the experimental data. It is shown that these relationships can be applicable in a wide range of Reynolds number, Re, up to Re < 1000 for the liquids with a flow behavior index, n, in the range of 0.5 < n < 1. The predicted coefficients from these relationships are in very good agreement with the experimental data given in the literature. (C) 1999 Elsevier Science S.A. All rights reserved.Öğe Theory of high-gradient magnetic filter performance(Ieee-Inst Electrical Electronics Engineers Inc, 1999) Abbasov, T; Koksal, M; Herdem, SA unique general model for high-gradient magnetic filters is presented. The functional dependence of the filter performance on the system's physical and geometrical parameters is derived. The derived theoretical expression makes it possible to explain both of the two different, apparently opposite, experimental results reported in the literature. The new quality factor does not include the suspension viscosity, but instead depends on the suspension density, which leads to the application of the formula for a larger class of filtration media including liquids, gases, and vapors.
