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Wyszukujesz frazę "Gorla, R. S. R." wg kryterium: Autor


Tytuł:
A numerical study of coupled non-linear equations of thermo-viscous fluid flow in cylindrical geometry
Autorzy:
Pothanna, N.
Aparna, P.
Gorla, R. S. R.
Powiązania:
https://bibliotekanauki.pl/articles/265510.pdf
Data publikacji:
2017
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
Reiner Rivlin Cross viscosity
thermal conductivity
thermo-stress viscosity
Prandtl number
lepkość
przenoszenie ciepła
liczba Prandtla
Opis:
In this paper we present numerical solutions to coupled non-linear governing equations of thermo-viscous fluid flow in cylindrical geometry using MATHEMATICA software solver. The numerical results are presented in terms of velocity, temperature and pressure distribution for various values of the material parameters such as the thermo-mechanical stress coefficient, thermal conductivity coefficient, Reiner Rivlin cross viscosity coefficient and the Prandtl number in the form of tables and graphs. Also, the solutions to governing equations for slow steady motion of a fluid have been obtained numerically and compared with the existing analytical results and are found to be in excellent agreement. The results of the present study will hopefully enable a better understanding applications of the flow under consideration.
Źródło:
International Journal of Applied Mechanics and Engineering; 2017, 22, 4; 965-979
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An intial-value technique for self-adjoint singularly perturbed two-point boundary value problems
Autorzy:
Padmaja, P.
Aparna, P.
Gorla, R. S. R.
Powiązania:
https://bibliotekanauki.pl/articles/264933.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
wartość początkowa
wartość brzegowa
perturbacja procesu
initial value technique
boundary value problem
singular perturbation problem
Opis:
In this paper, we present an initial value technique for solving self-adjoint singularly perturbed linearvboundary value problems. The original problem is reduced to its normal form and the reduced problem is converted to first order initial value problems. This replacement is significant from the computational point of view. The classical fourth order Runge-Kutta method is used to solve these initial value problems. This approach to solve singularly perturbed boundary-value problems is numerically very appealing. To demonstrate the applicability of this method, we have applied it on several linear examples with left-end boundary layer and rightend layer. From the numerical results, the method seems accurate and solutions to problems with extremely thin boundary layers are obtained.
Źródło:
International Journal of Applied Mechanics and Engineering; 2020, 25, 1; 106-126
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Bidirectionally stretched flow of Jeffrey liquid with nanoparticles, Rosseland radiation and variable thermal conductivity
Autorzy:
Archana, M.
Gireesha, B. J.
Rashidi, M. M.
Prasannakumara, B. C.
Gorla, R. S. R.
Powiązania:
https://bibliotekanauki.pl/articles/240409.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
heat mass transfer
jeffrey nanofluid
variable thermal conductivity
rosseland approximation
suction
ciepło
masa
zmienna przewodność cieplna
aproksymacja
ssanie
Opis:
Heat and mass transfer stretched flow of an incompressible, electrically conducting Jeffrey fluid has been studied numerically. Nanoparticles are suspended in the base fluid and it has many applications such as cooling of engines, thermal absorption systems, lubricants fuel cell, nanodrug delivery system and so on. Temperature dependent variable thermal conductivity with Rosseland approximation is taken into account and suction effect is employed in the boundary conditions. The governing partial differential equations are first transformed into set of ordinary differential equations using selected similarity transformations, which are then solved numerically using Runge-Kutta-Felhberg fourth-fifth order method along with shooting technique. The flow, heat and mass transfer characteristics with local Nusselt number for various physical parameters are presented graphically and a detailed discussion regarding the effect of flow parameters on velocity and temperature profiles are provided. It is found that, increase of variable thermal conductivity, radiation, Brownian motion and thermophoresis parameter increases the rate of heat transfer. Local Nusselt number has been computed for various parameters and it is observed that, in the presence of variable thermal conductivity and Rosseland approximation, heat transfer characteristics are higher as compared to the constant thermal conductivity and linear thermal radiation.
Źródło:
Archives of Thermodynamics; 2018, 39, 4; 33--57
1231-0956
2083-6023
Pojawia się w:
Archives of Thermodynamics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Boundary layer flow and heat transfer over a permeable shrinking cylinder with surface mass transfer
Autorzy:
Bhattacharyya, K.
Gorla, R. S. R.
Powiązania:
https://bibliotekanauki.pl/articles/955265.pdf
Data publikacji:
2013
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
warstwa graniczna
wymiana ciepła
wymiana masy
boundary layer
heat transfer
shrinking cylinder
mass suction
Opis:
In the present paper, the axisymmetric boundary layer flow and heat transfer past a permeable shrinking cylinder subject to surface mass transfer is studied. The similarity transformations are adopted to convert the governing partial differential equations for the flow and heat transfer into the nonlinear self-similar ordinary differential equations and then solved by a finite difference method using the quasilinearization technique. From the current investigation, it is found that the velocity in the boundary layer region decreases with the curvature parameter and increases with suction mass transfer. Moreover, with the increase of the curvature parameter, the suction parameter and Prandtl number, the heat transfer is enhanced.
Źródło:
International Journal of Applied Mechanics and Engineering; 2013, 18, 4; 1003-1012
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dual solutions for boundary layer flow of moving fluid over a moving surface with power-law surface temperature
Autorzy:
Mukhopadhyay, S.
Gorla, R. S. R.
Powiązania:
https://bibliotekanauki.pl/articles/265215.pdf
Data publikacji:
2013
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
przepływ konwekcyjny
przepływ płynu
temperatura powierzchni
forced convective flow
moving fluid
flat surface
power-law surface temperature
dual solutions
Opis:
An analysis of heat transfer for boundary layer forced convective flow past a moving flat surface parallel to a moving stream is presented. The power-law surface temperature at the boundary is prescribed. The surface temperature varying directly (or inversely) with power-law exponent is considered. The similarity solutions for the problem are obtained and the reduced ordinary differential equations are solved numerically. To support the validity of the numerical results, a comparison is made with known results from the open literature for some particular cases of the present study. When the surface and the fluid move in the opposite directions, dual solutions exist.
Źródło:
International Journal of Applied Mechanics and Engineering; 2013, 18, 1; 113-124
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of electric field on dispersion of a solute in an MHD flow through a vertical channel with and without chemical reaction
Autorzy:
Umavathi, J. C.
Kumar, J. P.
Gorla, R. S. R.
Gireesha, B. J.
Powiązania:
https://bibliotekanauki.pl/articles/265686.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
dyspersja Taylora
magnetohydrodynamika
reakcja chemiczna
Taylor dispersion
immiscible fluids
conducting fluid
MHD
chemical reaction
Opis:
The longitudinal dispersion of a solute between two parallel plates filled with two immiscible electrically conducting fluids is analyzed using Taylor’s model. The fluids in both the regions are incompressible and the transport properties are assumed to be constant. The channel walls are assumed to be electrically insulating. Separate solutions are matched at the interface using suitable matching conditions. The flow is accompanied by an irreversible first-order chemical reaction. The effects of the viscosity ratio, pressure gradient and Hartman number on the effective Taylor dispersion coefficient and volumetric flow rate for an open and short circuit are drawn in the absence and in the presence of chemical reactions. As the Hartman number increases the effective Taylor diffusion coefficient decreases for both open and short circuits. When the magnetic field remains constant, the numerical results show that for homogeneous and heterogeneous reactions, the effective Taylor diffusion coefficient decreases with an increase in the reaction rate constant for both open and short circuits.
Źródło:
International Journal of Applied Mechanics and Engineering; 2016, 21, 3; 683-711
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of heat source/sink and chemical reaction on MHD Maxwell nanofluid flow over a convectively heated exponentially stretching sheet using homotopy analysis method
Autorzy:
Sravanthi, C. S.
Gorla, R. S. R.
Powiązania:
https://bibliotekanauki.pl/articles/265865.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
reakcja chemiczna
źródło ciepła
materiały porowate
HAM
chemical reaction
heat source/sink
Maxwell nanofluid
porous exponentially stretching sheet
convective boundary conditions
Opis:
The aim of this paper is to study the effects of chemical reaction and heat source/sink on a steady MHD (magnetohydrodynamic) two-dimensional mixed convective boundary layer flow of a Maxwell nanofluid over a porous exponentially stretching sheet in the presence of suction/blowing. Convective boundary conditions of temperature and nanoparticle concentration are employed in the formulation. Similarity transformations are used to convert the governing partial differential equations into non-linear ordinary differential equations. The resulting non-linear system has been solved analytically using an efficient technique, namely: the homotopy analysis method (HAM). Expressions for velocity, temperature and nanoparticle concentration fields are developed in series form. Convergence of the constructed solution is verified. A comparison is made with the available results in the literature and our results are in very good agreement with the known results. The obtained results are presented through graphs for several sets of values of the parameters and salient features of the solutions are analyzed. Numerical values of the local skin-friction, Nusselt number and nanoparticle Sherwood number are computed and analyzed.
Źródło:
International Journal of Applied Mechanics and Engineering; 2018, 23, 1; 137-159
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Homotopy simulation of non-Newtonian Spriggs fluid flow over a flat plate with oscillating motion
Autorzy:
Ray, A. K.
Vasu, B.
Gorla, R. S. R.
Powiązania:
https://bibliotekanauki.pl/articles/265238.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
przepływ nieściśliwy
przepływy Stokes'a
płyn nienewtonowski
incompressible flow
oscillatory plate
Stokes second problem
HAM
non-Newtonian Spriggs fluid
Opis:
An incompressible flow of a non-Newtonian Spriggs fluid over an unsteady oscillating plate is investigated using the Homotopy Analysis Method (HAM). An analytic solution of sine and cosine oscillations of the plate has been obtained. The similarity transformation is introduced to reduce the governing partial differentia equations into a single non-linear dimensionless partial differential equation. The effects of the power index of Spriggs fluid and convergence control parameter of HAM for the flow are studied extensively. The range of the convergence control parameter for convergence of series solution for different values of the power index of Spriggs fluid is obtained. The solution for a Spriggs fluid is noticeably different from the solution obtained for a Newtonian fluid. The influences of the shear thinning and shear thickening fluid on the velocity profile are shown graphically. The transient flow effect is higher for non-Newtonian Spriggs fluid than that of a Newtonian fluid. It is also observed that the interval to reach the steady state for the cosine case is less than the sine case. The applications of Stokes’ second problem have been widely found in the variety of fields of biomedical, medical, chemical, micro and nanotechnology.
Źródło:
International Journal of Applied Mechanics and Engineering; 2019, 24, 2; 359-385
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
MHD free convection-radiation interaction in a porous medium - part I: numerical investigation
Autorzy:
Vasu, B.
Gorla, R. S. R.
Murthy, P. V. S. N.
Prasad, V. R.
Bég, O. Anwar
Siddiqa, S.
Powiązania:
https://bibliotekanauki.pl/articles/266199.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
pole magnetyczne
metoda Keller-Box
nośnik porowaty
implicit finite difference scheme
Keller-Box method
magnetic field
horizontal circular cylinder
Opis:
A numerical investigation of two dimensional steady magnetohydrodynamics heat and mass transfer by laminar free convection from a radiative horizontal circular cylinder in a non-Darcy porous medium is presented by taking into account the Soret/Dufour effects. The boundary layer conservation equations, which are parabolic in nature, are normalized into non-similar form and then solved numerically with the well-tested, efficient, implicit, stable Keller–Box finite-difference scheme. We use simple central difference derivatives and averages at the mid points of net rectangles to get finite difference equations with a second order truncation error. We have conducted a grid sensitivity and time calculation of the solution execution. Numerical results are obtained for the velocity, temperature and concentration distributions, as well as the local skin friction, Nusselt number and Sherwood number for several values of the parameters. The dependency of the thermophysical properties has been discussed on the parameters and shown graphically. The Darcy number accelerates the flow due to a corresponding rise in permeability of the regime and concomitant decrease in Darcian impedance. A comparative study between the previously published and present results in a limiting sense is found in an excellent agreement.
Źródło:
International Journal of Applied Mechanics and Engineering; 2020, 25, 1; 198-218
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
MHD free convection-radiation interaction in a porous medium - part II: soret/dufour effects
Autorzy:
Vasu, B.
Gorla, Rama Subba Reddy
Murthy, P. V. S. N.
Prasad, V. R.
Beg, O. A.
Siddiqa, S.
Powiązania:
https://bibliotekanauki.pl/articles/266156.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
materiały porowate
pole magnetyczne
magnetohydrodynamika
non-Darcy porous media transport
magnetic field
horizontal circular cylinder
Soret number
Dufour number
Opis:
This paper is focused on the study of two dimensional steady magnetohydrodynamics heat and mass transfer by laminar free convection from a radiative horizontal circular cylinder in a non-Darcy porous medium by taking into account of the Soret/Dufour effects. The boundary layer equations, which are parabolic in nature, are normalized into non-similar form and then solved numerically with the well-tested, efficient, implicit, stable Keller–Box finite-difference scheme. Numerical results are obtained for the velocity, temperature and concentration distributions, as well as the local skin friction, Nusselt number and Sherwood number for several values of the parameters, namely the buoyancy ratio parameter, Prandtl number, Forchheimer number, magnetohydrodynamic body force parameter, Soret and Dufour numbers. The dependency of the thermophysical properties has been discussed on the parameters and shown graphically. Increasing the Forchheimer inertial drag parameter reduces velocity but elevates temperature and concentration. Increasing the Soret number and simultaneously reducing the Dufour number greatly boosts the local heat transfer rate at the cylinder surface. A comparative study of the previously published and present results in a limiting sense is made and an excellent agreement is found between the results.
Źródło:
International Journal of Applied Mechanics and Engineering; 2020, 25, 2; 157-175
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
MHD mixed convection in copper-water nanofluid filled lid-driven square cavity containing multiple adiabatic obstacles with discrete heating
Autorzy:
Gorla, R. S. R.
Siddiqa, S.
Hasan, A. A.
Salah, T.
Rashad, A. M.
Powiązania:
https://bibliotekanauki.pl/articles/265383.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
nanociecze
konwekcja mieszana
magnetohydrodynamika
nanofluid
mixed convection
magnetohydrodynamics
square cavity
adiabatic obstacles
Opis:
The objective of the present work is to investigate the influence of nanoparticles of copper within the base fluid (water) on magneto-hydrodynamic mixed-convection flow in a square cavity with internal generation. A control finite volume method and SIMPLER algorithm are used in the numerical calculations. The geometry is a lid-driven square cavity with four interior square adiabatic obstacles. A uniform heat source is located in a part of the left wall and a part of the right wall of the enclosure is maintained at cooler temperature while the remaining parts of the two walls are thermally insulated. Both the upper and bottom walls of the cavity are considered to be adiabatic. A comparison with previously published works shows a very good agreement. It is observed that the Richardson number, Ri, significantly alters the behavior of streamlines when increased from 0.1 to 100.0. Also, the heat source position parameter, D, significantly changes the pattern of isotherms and its strength shifted when D moves from 0.3 to 0.7.
Źródło:
International Journal of Applied Mechanics and Engineering; 2020, 25, 2; 57-74
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Natural convection and radiation in a radial porous fin with variable thermal conductivity
Autorzy:
Darvishi, M. T.
Kani, F.
Gorla, R. S. R.
Powiązania:
https://bibliotekanauki.pl/articles/955178.pdf
Data publikacji:
2014
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
konwekcja naturalna
promieniowanie
wydajność cieplna
metoda kolokacji
porous radial fin
natural convection
radiation
thermal performance
spectral collocation method
Opis:
In this study, the effects of radiation and convection heat transfer in a radial porous fin are considered. The geometry considered is that of a rectangular profile fin. The porous fin allows the flow to infiltrate through it and solid-fluid interaction takes place. This study is performed using Darcy’s model to formulate the heat transfer equation. The thermal conductivity is assumed to be a function of temperature. The effects of the natural convection parameter Nc , radiation parameter Nr and thermal conductivity parameter m on the dimensionless temperature distribution and heat transfer rate are discussed. The results suggest that the radiation transfers more heat than a similar model without radiation.
Źródło:
International Journal of Applied Mechanics and Engineering; 2014, 19, 1; 27-37
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical solutions by EFGM of MHD convective fluid flow past a vertical plate immersed in a porous medium in the presence of cross diffusion effects via biot number and convective boundary condition
Autorzy:
Raju, R. S.
Reddy, B. M.
Rashidi, M. M.
Gorla, R. S. R.
Powiązania:
https://bibliotekanauki.pl/articles/265443.pdf
Data publikacji:
2017
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
thermal diffusion
diffusion thermo
MHD
porous medium
EFGM
dyfuzja termiczna
magnetohydrodynamika
porowatość
Opis:
In this investigation, the numerical results of a mixed convective MHD chemically reacting flow past a vertical plate embedded in a porous medium are presented in the presence of cross diffusion effects and convective boundary condition. Instead of the commonly used conditions of constant surface temperature or constant heat flux, a convective boundary condition is employed which makes this study unique and the results more realistic and practically useful. The momentum, energy, and concentration equations derived as coupled second-order, ordinary differential equations are solved numerically using a highly accurate and thoroughly tested element free Galerkin method (EFGM). The effects of the Soret number, Dufour number, Grashof number for heat and mass transfer, the viscous dissipation parameter, Schmidt number, chemical reaction parameter, permeability parameter and Biot number on the dimensionless velocity, temperature and concentration profiles are presented graphically. In addition, numerical results for the local skin-friction coefficient, the local Nusselt number, and the local Sherwood number are discussed through tabular forms. The discussion focuses on the physical interpretation of the results as well as their comparison with the results of previous studies.
Źródło:
International Journal of Applied Mechanics and Engineering; 2017, 22, 3; 613-636
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Probabilistic study of bone remodeling using finite element analysis
Autorzy:
Werner, C.
Gorla, R. S. R.
Powiązania:
https://bibliotekanauki.pl/articles/265649.pdf
Data publikacji:
2013
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
analiza probabilistyczna
przebudowa kości
analiza elementów skończonych
probabilistic analysis
bone remodeling
finite element analysis
Opis:
The dynamic bone remodeling process is a computationally challenging research area that struggles to understand the actual mechanisms. It has been observed that a mechanical stimulus in the bone greatly affects the remodeling process. A 3D finite element model of a femur is created and a probabilistic analysis is performed on the model. The probabilistic analysis measures the sensitivities of various parameters related to the material properties, geometric properties, and the three load cases defined as Single Leg Stance, Abduction, and Adduction. The sensitivity of each parameter is based on the calculated maximum mechanical stimulus and analyzed at various values of probabilities ranging from 0.001 to 0.999. The analysis showed that the parameters associated with the Single Leg Stance load case had the highest sensitivity with a probability of 0.99 and the angle of the force applied to the joint of the proximal femur had the overall highest sensitivity.
Źródło:
International Journal of Applied Mechanics and Engineering; 2013, 18, 3; 911-921
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Radiation absorption and chemical reaction effects on Rivlin-Ericksen flow past a vertical moving porous plate
Autorzy:
Sravanthi, C. S.
Gorla, R. S. R.
Powiązania:
https://bibliotekanauki.pl/articles/264592.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
płyn Rivlina-Ericksena
absorpcja promieniowania
reakcja chemiczna
ssanie
Rivlin-Ericksen fluid
radiation absorption
chemical reaction
variable temperature
concentration
suction
Opis:
An analysis has been carried out to study the combined effects of radiation absorption and chemical reaction on an incompressible, electrically conducting and radiating flow of a Rivlin-Ericksen fluid along a semi-infinite vertical permeable moving plate in the presence of a transverse applied magnetic field. It is assumed that the suction velocity, the temperature and the concentration at the wall are exponentially varying with time. The dimensionless governing equations for this investigation are solved analytically using two-term harmonic and non-harmonic functions. A comparison is made with the available results in the literature for a special case and our results are in very good agreement with the known results. A parametric study of the physical parameters is made and results are presented through graphs and tables. The results indicate that the fluid velocity and temperature could be controlled by varying the radiation absorption.
Źródło:
International Journal of Applied Mechanics and Engineering; 2019, 24, 3; 675-689
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł

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