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Joao N N Quaresma - One of the best experts on this subject based on the ideXlab platform.
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a review of hybrid Integral Transform solutions in fluid flow problems with heat or mass transfer and under navier stokes equations formulation
Numerical Heat Transfer Part B-fundamentals, 2019Co-Authors: R M Cotta, Kleber Marques Lisboa, Emanuel Negrao Macedo, Joao N N Quaresma, Marcos Filardy Curi, Stavroula Balabani, Jesus S Perezguerrero, Nelson S AmorimAbstract:The Generalized Integral Transform Technique (GITT) is reviewed as a hybrid numerical–analytical approach for fluid flow problems, with or without heat and mass transfer, here with emphasis on the ...
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Integral Transform solution of micropolar magnetohydrodynamic oscillatory flow with heat and mass transfer over a plate in a porous medium subjected to chemical reactions
Elsevier, 2019Co-Authors: Fabio A. Pontes, Helder K. Miyagawa, Péricles C. Pontes, Emanuel N. Macêdo, Joao N N QuaresmaAbstract:The main goal of the present work is to show the procedure, application and main features of the hybrid numerical-analytical approach known as GITT (Generalized Integral Transform Technique) by solving an unsteady, one-dimensional magnetohydrodynamic (MHD) oscillatory flow of a micropolar and incompressible fluid with heat and mass transfer through a permeable vertical plate embedded in a porous medium in the presence of chemical reaction. The mathematical formulation of the studied model was obtained from the equation of motion and the mass and energy balances by considering laminar and incompressible flow subjected to a constant transverse magnetic field with constant physical properties. Convergence analysis was performed and presented to illustrate the consistency of the Integral Transform technique. Linear and angular velocities distribution, temperature and concentration profiles were generated and numerically verified with an approximate solution found in the literature and with the results of the method of lines (MOL) with good agreement. The effects of some governing parameters, namely, dimensionless time, magnetic field parameter, Schmidt and Prandtl numbers, permeability and chemical reaction parameters, on these fields were presented. The effects of these parameters on the local skin friction coefficient, the couple stress coefficient, the local Nusselt number and the local Sherwood number were also critically evaluated. Therefore, results show that the linear velocity decreases with increasing magnetic field parameter, while the angular velocity increases with increasing the same and the linear and angular velocities and the concentration field decrease as the Schmidt number increases while the temperature field decreases with increasing Prandtl number. Keywords: Generalized Integral Transform Technique (GITT), Equations of Motion, Magnetohydrodynamic (MHD), Heat and mass transfer, Porous Medium, Chemical reactio
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Integral Transform solution of micropolar magnetohydrodynamic oscillatory flow with heat and mass transfer over a plate in a porous medium subjected to chemical reactions
Journal of King Saud University - Science, 2017Co-Authors: Fabio De Andrade Pontes, Emanuel Negrao Macedo, Helder K. Miyagawa, Péricles C. Pontes, Joao N N QuaresmaAbstract:Abstract The main goal of the present work is to show the procedure, application and main features of the hybrid numerical-analytical approach known as GITT (Generalized Integral Transform Technique) by solving an unsteady, one-dimensional magnetohydrodynamic (MHD) oscillatory flow of a micropolar and incompressible fluid with heat and mass transfer through a permeable vertical plate embedded in a porous medium in the presence of chemical reaction. The mathematical formulation of the studied model was obtained from the equation of motion and the mass and energy balances by considering laminar and incompressible flow subjected to a constant transverse magnetic field with constant physical properties. Convergence analysis was performed and presented to illustrate the consistency of the Integral Transform technique. Linear and angular velocities distribution, temperature and concentration profiles were generated and numerically verified with an approximate solution found in the literature and with the results of the method of lines (MOL) with good agreement. The effects of some governing parameters, namely, dimensionless time, magnetic field parameter, Schmidt and Prandtl numbers, permeability and chemical reaction parameters, on these fields were presented. The effects of these parameters on the local skin friction coefficient, the couple stress coefficient, the local Nusselt number and the local Sherwood number were also critically evaluated. Therefore, results show that the linear velocity decreases with increasing magnetic field parameter, while the angular velocity increases with increasing the same and the linear and angular velocities and the concentration field decrease as the Schmidt number increases while the temperature field decreases with increasing Prandtl number.
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Integral Transform solutions for the analysis of hydrodynamic lubrication of journal bearings
Tribology International, 2012Co-Authors: E N Santos, Claudio Jose Cavalcante Blanco, Emanuel Negrao Macedo, C E Maneschy, Joao N N QuaresmaAbstract:Abstract This work deals with analysis of hydrodynamic lubrication of radial journal bearings. The Reynolds equation was treated in order to obtain a hybrid numerical–analytical solution through the Generalized Integral Transform Technique (GITT) for the problem. A parametric analysis is done to investigate the influence of typical governing parameters for such a physical situation. Numerical results for engineering parameters such as pressure field, friction coefficient, axial flow rate and dimensionless load capacity were thus produced as functions of such parameters. Comparisons with results presented in the literature were also performed in order to verify the present results, as well as to demonstrate the consistency of the final results and the capacity of the GITT approach in handling journal bearing problems.
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thermal entry region analysis through the finite Integral Transform technique in laminar flow of bingham fluids within concentric annular ducts
International Journal of Heat and Mass Transfer, 2002Co-Authors: U C S Nascimento, Emanuel Negrao Macedo, Joao N N QuaresmaAbstract:Abstract The heat transfer characteristics of Bingham plastics fluids within concentric annular ducts are analytically studied through the classical finite Integral Transform technique. In the analysis of the thermal entry region, four types of boundary conditions are adopted and prescribed either at the inner or outer duct wall, and the flow is considered to be laminar and fully developed. Local Nusselt numbers are computed along the channel length with high accuracy for different values of aspect ratios and yield numbers, which are systematically tabulated and graphically presented. Comparisons with previous works in the literature are also performed for typical situations, in order to validate the numerical codes developed in this work, as well as to demonstrate that consistent results were produced.
R M Cotta - One of the best experts on this subject based on the ideXlab platform.
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vector eigenfunction expansion in the Integral Transform solution of transient natural convection
International Journal of Numerical Methods for Heat & Fluid Flow, 2019Co-Authors: Kleber Marques Lisboa, R M CottaAbstract:The purpose of this work is to revisit the Integral Transform solution of transient natural convection in differentially heated cavities considering a novel vector eigenfunction expansion for handling the Navier-Stokes equations on the primitive variables formulation.,The proposed expansion base automatically satisfies the continuity equation and, upon Integral Transformation, eliminates the pressure field and reduces the momentum conservation equations to a single set of ordinary differential equations for the Transformed time-variable potentials. The resulting eigenvalue problem for the velocity field expansion is readily solved by the Integral Transform method itself, while a traditional Sturm–Liouville base is chosen for expanding the temperature field. The coupled Transformed initial value problem is numerically solved with a well-established solver based on a backward differentiation scheme.,A thorough convergence analysis is undertaken, in terms of truncation orders of the expansions for the vector eigenfunction and for the velocity and temperature fields. Finally, numerical results for selected quantities are critically compared to available benchmarks in both steady and transient states, and the overall physical behavior of the transient solution is examined for further verification.,A novel vector eigenfunction expansion is proposed for the Integral Transform solution of the Navier–Stokes equations in transient regime. The new physically inspired eigenvalue problem with the associated integmaral Transformation fully shares the advantages of the previously obtained Integral Transform solutions based on the streamfunction-only formulation of the Navier–Stokes equations, while offering a direct and formal extension to three-dimensional flows.
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a review of hybrid Integral Transform solutions in fluid flow problems with heat or mass transfer and under navier stokes equations formulation
Numerical Heat Transfer Part B-fundamentals, 2019Co-Authors: R M Cotta, Kleber Marques Lisboa, Emanuel Negrao Macedo, Joao N N Quaresma, Marcos Filardy Curi, Stavroula Balabani, Jesus S Perezguerrero, Nelson S AmorimAbstract:The Generalized Integral Transform Technique (GITT) is reviewed as a hybrid numerical–analytical approach for fluid flow problems, with or without heat and mass transfer, here with emphasis on the ...
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Integral Transform solution of internal flow problems based on navier stokes equations and primitive variables formulation
International Journal for Numerical Methods in Engineering, 2007Co-Authors: G G C De Lima, Carlos Antonio Cabral Dos Santos, A Haag, R M CottaAbstract:The generalized Integral Transform technique (GITT) is employed in the solution of incompressible laminar channel flows as formulated by the steady-state Navier–Stokes and continuity equations under the primitive variables mathematical representation. A hybrid numerical–analytical solution is developed based on eigenfunction expansions in one space co-ordinate and error-controlled numerical solution of the resulting system of coupled ordinary differential equations in the remaining space direction. The approach is illustrated for developing flow between parallel-plates with uniform and irrotational inlet flow condition. The conventional Poisson-type equation for the pressure field with appropriate boundary conditions is also Transformed and simultaneously solved with the momentum equation along the longitudinal direction, by considering eigenvalue problems for each of the two potentials, defined in the transversal direction. The transversal velocity component is then explicitly determined from the continuity equation. Numerical results of the longitudinal velocity component and friction factor fields are reported to illustrate the convergence behaviour and user prescribed error control inherent to the proposed hybrid approach. Critical comparisons with previous contributions on the same method that made use of the streamfunction-only formulation are also provided. Copyright © 2006 John Wiley & Sons, Ltd.
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Integral Transform solution of a two dimensional model for contaminant dispersion in rivers and channels with spatially variable coefficients
Environmental Modelling and Software, 2006Co-Authors: F P J De Barros, W B Mills, R M CottaAbstract:The Generalized Integral Transform Technique (GITT) is employed to obtain numerical-analytical solutions for mathematical models that predict the dispersion of dissolved pollutants in rivers, streams and channels with either symmetric or asymmetric flow. The two-dimensional steady-state model presented allows for the use of variable coefficients represented by non-uniform velocity profiles and turbulent diffusion coefficients, in any general functional form. The proposed model is then applied to an example of biocides contamination downstream of thermohydroelectric power stations, originated from the cleaning of cooling water systems undergoing biofouling.
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Integral Transform solutions of transient natural convection in enclosures with variable fluid properties
International Journal of Heat and Mass Transfer, 2000Co-Authors: M A Leal, H A Machado, R M CottaAbstract:Abstract This paper is aimed at the application of the Generalized Integral Transform Technique to the transient version of the classical differentially heated square cavity problem, considering both constant and variable fluid properties. The streamfunction-only formulation of the flow equations and the associated energy equation under laminar flow regime are employed in seeking a hybrid numerical–analytical solution to this natural convection problem. The computational procedure is carefully validated and a thorough convergence analysis is undertaken, yielding sets of reference results. The computed transient behavior of the coupled heat and fluid flow phenomena is compared to some previously reported results. The solution for variable fluid properties with partial Boussinesq approximation (density variation in the body force term only) is presented and compared with the constant properties results. Both models are investigated for different values of the Rayleigh number, from 103 to 105, and Prandtl number equal to 0.71.
Emanuel Negrao Macedo - One of the best experts on this subject based on the ideXlab platform.
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a review of hybrid Integral Transform solutions in fluid flow problems with heat or mass transfer and under navier stokes equations formulation
Numerical Heat Transfer Part B-fundamentals, 2019Co-Authors: R M Cotta, Kleber Marques Lisboa, Emanuel Negrao Macedo, Joao N N Quaresma, Marcos Filardy Curi, Stavroula Balabani, Jesus S Perezguerrero, Nelson S AmorimAbstract:The Generalized Integral Transform Technique (GITT) is reviewed as a hybrid numerical–analytical approach for fluid flow problems, with or without heat and mass transfer, here with emphasis on the ...
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Integral Transform solution of micropolar magnetohydrodynamic oscillatory flow with heat and mass transfer over a plate in a porous medium subjected to chemical reactions
Journal of King Saud University - Science, 2017Co-Authors: Fabio De Andrade Pontes, Emanuel Negrao Macedo, Helder K. Miyagawa, Péricles C. Pontes, Joao N N QuaresmaAbstract:Abstract The main goal of the present work is to show the procedure, application and main features of the hybrid numerical-analytical approach known as GITT (Generalized Integral Transform Technique) by solving an unsteady, one-dimensional magnetohydrodynamic (MHD) oscillatory flow of a micropolar and incompressible fluid with heat and mass transfer through a permeable vertical plate embedded in a porous medium in the presence of chemical reaction. The mathematical formulation of the studied model was obtained from the equation of motion and the mass and energy balances by considering laminar and incompressible flow subjected to a constant transverse magnetic field with constant physical properties. Convergence analysis was performed and presented to illustrate the consistency of the Integral Transform technique. Linear and angular velocities distribution, temperature and concentration profiles were generated and numerically verified with an approximate solution found in the literature and with the results of the method of lines (MOL) with good agreement. The effects of some governing parameters, namely, dimensionless time, magnetic field parameter, Schmidt and Prandtl numbers, permeability and chemical reaction parameters, on these fields were presented. The effects of these parameters on the local skin friction coefficient, the couple stress coefficient, the local Nusselt number and the local Sherwood number were also critically evaluated. Therefore, results show that the linear velocity decreases with increasing magnetic field parameter, while the angular velocity increases with increasing the same and the linear and angular velocities and the concentration field decrease as the Schmidt number increases while the temperature field decreases with increasing Prandtl number.
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Integral Transform solutions for the analysis of hydrodynamic lubrication of journal bearings
Tribology International, 2012Co-Authors: E N Santos, Claudio Jose Cavalcante Blanco, Emanuel Negrao Macedo, C E Maneschy, Joao N N QuaresmaAbstract:Abstract This work deals with analysis of hydrodynamic lubrication of radial journal bearings. The Reynolds equation was treated in order to obtain a hybrid numerical–analytical solution through the Generalized Integral Transform Technique (GITT) for the problem. A parametric analysis is done to investigate the influence of typical governing parameters for such a physical situation. Numerical results for engineering parameters such as pressure field, friction coefficient, axial flow rate and dimensionless load capacity were thus produced as functions of such parameters. Comparisons with results presented in the literature were also performed in order to verify the present results, as well as to demonstrate the consistency of the final results and the capacity of the GITT approach in handling journal bearing problems.
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thermal entry region analysis through the finite Integral Transform technique in laminar flow of bingham fluids within concentric annular ducts
International Journal of Heat and Mass Transfer, 2002Co-Authors: U C S Nascimento, Emanuel Negrao Macedo, Joao N N QuaresmaAbstract:Abstract The heat transfer characteristics of Bingham plastics fluids within concentric annular ducts are analytically studied through the classical finite Integral Transform technique. In the analysis of the thermal entry region, four types of boundary conditions are adopted and prescribed either at the inner or outer duct wall, and the flow is considered to be laminar and fully developed. Local Nusselt numbers are computed along the channel length with high accuracy for different values of aspect ratios and yield numbers, which are systematically tabulated and graphically presented. Comparisons with previous works in the literature are also performed for typical situations, in order to validate the numerical codes developed in this work, as well as to demonstrate that consistent results were produced.
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forced convection in thermally developing turbulent flow of drag reducing fluids within circular tubes
International Journal of Heat and Mass Transfer, 2000Co-Authors: Emanuel Negrao Macedo, C E Maneschy, Joao N N QuaresmaAbstract:Abstract The Integral Transform Technique is used to solve the turbulent forced convection problem for drag-reducing fluids in the thermal developing and fully developed regions within circular tubes. Turbulent effects are taken into account through an algebraic model corresponding to the minimum-drag asymptotic case for viscoelastic fluids. The well-established Sign-Count Method and the Generalized Integral Transform Technique (GITT) are both employed in order to compute the eigenvalues and the respective eigenfunctions of the associated Sturm–Liouville problem. The Nusselt numbers calculated with the present approach are then compared with those obtained from experimental works available in the literature.
J N Salunke - One of the best experts on this subject based on the ideXlab platform.
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The Double Bi Lateral Laplace Transform is used to find the Bi-Lateral Laplace- Mellin Integral Transform in the range [- ∞,0] to [ ∞, ∞ ].We have derived the different
2014Co-Authors: S M Khairnar, R M Pise, J N SalunkeAbstract:Abstract: In this paper we discuss Bi-lateral Laplace–Mellin Integral Transform technique for solving boundary and initial value problems. This Transform is studied in the infinite region [- ∞ , 0] to [ ∞, ∞]. We investigate the properties and theorems like inversion theorem, convolution theorem, Parseval’s theorem and some properties by using Ramanujan’s formula. To illustrate the advantages and use of this Transformation Cauchy’s differential equation have been solved. This work gives us an insight to understand how this Transform can be used for finding the relations with other Integral Transforms. We have also studied graphical representation of Bi-lateral Laplace–Mellin Integral Transfor
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relation of finite mellin Integral Transform with laplace and fourier Transforms
2011Co-Authors: S M Khairnar, R M Pise, J N SalunkeAbstract:The aim of this paper is to derive the relation between the Finite Mellin Integral Transform with the Laplace Transform by using the double Laplace and Fourier – Finite Mellin Integral. Properties like linearity property, scaling roperty, power property and f(ax)g(by) are also derived. The shifting and inversion theorems for Laplace-Finite Mellin Integral ransform and Fourier-Finite Mellin Integral Transforms are also discussed.
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applications of the mellin type Integral Transform in the range 1 a
2011Co-Authors: S M Khairnar, R M Pise, J N SalunkeAbstract:In this paper Laplace operators are used to solve the Mellin Type Integral Transform which can be a technique for solving boundary and initial value problems .This Transforms is applicable in the infinite interval. This work intends to understand how Laplce operators leads to properties and relations with the Mellin Type Integral Transform .The main objective of this work is to find the relation between Laplace Transform and the Mellin Type Integral Transform in(1/a, ). The results have been modified by applying suitable functions which leads to the results of Mellin Type Integral Transform in the interval t a / 1 .We illustrate the use of this Transformation by solving the Cauchy differential equation with the help of Matlab.
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bilateral laplace mellin Integral Transform and its applications
2010Co-Authors: S M Khairnar, J N SalunkeAbstract:In this paper we discuss Bi-lateral Laplace-Mellin Integral Transform technique for solving boundary and initial value pr oblems. This Transform is studied in the infinite region (-∞ , 0) to ( ∞ ∞, ). We investigate the properties and theorems li ke inversion theorem, convolution theorem, Parseval's theorem and some properties by using Ramanujan's formula. To illustrate the advantages aof this Transformation Cauchy's differential equation have been solved. This work g ives us an insight to understand how this Transform can be used for finding the relations wit h other Integral Transforms. We have also studied graphical representation of Bi-lateral Laplace-Mellin Integral Transform using Matlab.
Virginia Kiryakova - One of the best experts on this subject based on the ideXlab platform.
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the mellin Integral Transform in fractional calculus
Fractional Calculus and Applied Analysis, 2013Co-Authors: Yuri Luchko, Virginia KiryakovaAbstract:In Fractional Calculus (FC), the Laplace and the Fourier Integral Transforms are traditionally employed for solving different problems. In this paper, we demonstrate the role of the Mellin Integral Transform in FC. We note that the Laplace Integral Transform, the sin- and cos-Fourier Transforms, and the FC operators can all be represented as Mellin convolution type Integral Transforms. Moreover, the special functions of FC are all particular cases of the Fox H-function that is defined as an inverse Mellin Transform of a quotient of some products of the Gamma functions.
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the obrechkoff Integral Transform properties and relation to a generalized fractional calculus
Numerical Functional Analysis and Optimization, 2000Co-Authors: I Dimovski, Virginia KiryakovaAbstract:This survey is devoted to one of the most general Laplace-type Integral Transforms, the so-called Obrechkoff Integral Transform, introduced and studied for the first time by Obrechkoff[25]. It has been modified by Dimovski [5],[6] and used as a basis of a Mikusinski-type operational calculus for the hyper-Bessel differential operators of arbitrary order. Later, in a series of papers Dimovski and Kiryakova [8],[9],[10] have found operational properties, complex and real inversion formulas, Abel-type theorems for the Obrechkoff Transform. This theory has been further developed by Kiryakova [16],[17],[18] using the tools of the Meijer's G-functions and of the fractional calculus. Namely, a new definition as a G-Transform has been given for the Obrechkoff Transform. The hyper-Bessel operators themselves, have given rise to a new generalized fractional calculus and further extensive use of the G-functions. Many other generalized differentiation and integration operators happen to be special cases in this calcu...