Ramana Murthy Josyula

• M.Sc (App. Mathematics), Ph.D
• National Institute of Technology Warangal

The investigativestudy of continuousflow of micro-polar fluid past a spherical porous ballsaturated with viscous fluidis considered. The velocity field within as well as outside the sphere is referred in terms of stream function. The flow pattern is obtained under regularity condition at infinity and normal velocity continuity on the sphere's surfa...

This study assesses the dynamics of electromagnetohydrodynamic (EMHD) flow of couple stress fluid through a circular cylinder. The flow is assumed to be driven by electromagnetic force and applied pressure gradient. A comprehensive theoretical framework is developed to solve the Poisson–Boltzmann equation (under the Debye–Hückel approximation) for...

The exact solution for the unsteady magnetohydrodynamic flow of dusty fluid through a circular cylinder is investigated. We assume that the dust particles are uniformly scattered throughout the flow field. An external magnetic force is imposed across the cylinder surface, normal to the flow direction. The equations governing the flow of fluid and d...

The present article discusses the solute transport process in steady laminar blood flow through a non-Darcy porous medium, as a model for drug movement in blood vessels containing deposits. The Darcy–Brinkman–Forchheimer drag force formulation is adopted to mimic a sparsely packed porous domain, and the vessel is approximated as an impermeable cyli...

The study of oscillating flow of a Couple Stress fluid past a permeable sphere is considered. Analytical solution for the flow field in terms of stream function is obtained using modified Bessel functions. The formula for Drag acting on the sphere due external flow is evaluated. Pressure field for the flow region past and inside the sphere is obtai...

In this paper, couple stress fluid flow in a rectangular channel generated due to applied transverse magnetic field. Since the magnetic parameter is very small, the induced magnetic field is neglected. The 4th order PDE for axial velocity w is solved under i) the no slip and ii) hyper stick boundary conditions. The velocity w is obtained in Fourier...

In this paper, an attempt is made to study the flow generated by rotary oscillations of a permeable sphere in an infinite expanse of an incompressible couple stress fluid. The flow generated is solved under Stokesian assumption for velocity field in the form of modified Bessel functions. The couple acting on the sphere due to external flow as well...

The laminar viscous fluid flow past a circular cylinder placed in a square cavity of a uniform cross‐section is generated by applying injection/suction at the adjacent sidewalls. The temperature on the side walls without suction and on the boundary of the cylinder is kept constant, and constant heat flux is maintained on the walls with suction. The...

In this paper, we study laminar viscous fluid flow about a circular cylinder placed in a square cavity of uniform cross-section generated by applying injection/suction at the opposite-side walls. Constant temperature is maintained on the walls without suction and on the boundary of the cylinder and constant heat flux is maintained on the walls with...

The flow of an incompressible viscous fluid under the influence of an applied uniform magnetic field in a rectangular channel with suction at the adjacent two side walls is studied by considering Hall current and Joule heating effects. The rectangular channel is subjected to a uniform suction from top wall and injection from right wall. An external...

The purpose for this paper is to study heat transfer in a rectangular channel with suction applied at the adjacent two side walls. A two‐dimensional laminar viscous fluid flow is generated due to the application of suction/injection. The other two opposite sides are kept at a constant temperatures, and the walls with suction are maintained at a con...

The problem of the longitudinal oscillations of a circular cylinder along its axis of symmetry in an incompressible micro-polar fluid and the flow generated due to these oscillations in the fluid is considered. The Stokes flow is considered by neglecting nonlinear convective terms in the equations of motion on the assumption that the flow is so slo...

The flow due to a circular cylinder oscillating rectilinearly, about its axis of symmetry in a couple-stress fluid is considered. There occurs a rare but an important special case referred to as resonance flow. The material constants satisfy a specific relation called resonance condition. In this case, the flow is analyzed under Stokesian approxima...

Uniform flow of a viscous fluid past a permeable circular cylinder is considered. The flow across the surface of permeable cylinder is possible due to jump in the pressure at the surface. The flow pattern for the outer and inner regions of the cylinder is obtained in terms of stream function. The bounds for the permeability parameter are estimated....

Steady-state temperature distribution in a rectangular plane sheet with nonhomogeneous boundary conditions is solved using Fourier series. The results are compared with the numerical results. For different values of geometric ratio, the isothermal curves are obtained.

The present paper investigates analytically the two-dimensional heat transfer and entropy generation characteristics of axisymmetric, incompressible viscous fluid flow in a horizontal circular pipe. The flow is subjected to an externally applied uniform suction across the wall in the normal direction and a constant magnetic field. Constant wall tem...

An analysis is carried out to study the influence of thermal radiation on the unsteady MHD flow, heat and mass transfer on a radially stretching sheet immersed in a chemically reactive Jeffrey nanofluid. Using Homotopy Analysis Method (HAM) analytical solutions are obtained for the flow variables. The h-curves for the velocity, temperature and nano...

A theoretical model of time-dependent peristaltic viscous fluid flow through a curved channel in the presence of an applied magnetic field is investigated. The results for stream function, pressure distribution and mechanical efficiency are obtained under the assumptions of long wavelength and low Reynolds number approximation. Pressure fluctuation...

An analysis is presented to investigate the effects of radiative heat transfer on entropy generation in flow of two immiscible non-Newtonian fluids between two horizontal parallel plates. Both the plates are maintained at constant temperatures higher than that of the fluid. The Stokes’ couple stress flow model is employed. The flow region consists...

The analytical study of the flow generated by the slow steady rotation of a permeable sphere in an incompressible micro-polar fluid is considered. Both the flows internal and external to the sphere are coupled. The result will degenerate to independent equations for the case of viscous fluids for the inner and external flows. The flow field in the...

An analytical study of the entropy generation rate and heat transfer in a flow of immiscible couple stress fluids between two horizontal parallel plates under a constant pressure gradient is performed. Both plates are kept at different and constant temperatures higher than that of the fluid. The Stokes couple stress flow model is employed. The clas...

The purpose of this paper is to examine the flow, heat transfer and entropy generation characteristics for an inclined channel of two immiscible micropolar fluids. Design/methodology/approach – The flow region consists of two zones, the flow of the heavier fluid taking place in the lower zone. The flow is assumed to be governed by Eringen's micropo...

Purpose – The purpose of this paper is to examine the flow, heat transfer and entropy generation characteristics for an inclined channel of two immiscible micropolar fluids. Design/methodology/approach – The flow region consists of two zones, the flow of the heavier fluid taking place in the lower zone. The flow is assumed to be governed by Eringe...

In this paper, the flow generated by the slow steady rotation of a permeable sphere with thin surface about its axis of symmetry in an incompressible couple stress fluid which is otherwise at rest is studied. Expressions for the velocity and couple stress tensor components are obtained in terms of modified Bessel functions and Gagenbauer’s polynomi...

The present investigation extends a consideration of peristaltic flow in curved channels through the second-law analysis. The lubrication approximation is employed to linearize the momentum, energy, and entropy generation rate equations. The stream function and temperature distribution are used to calculate the entropy generation number and the Bej...

This work investigates the effect of entropy generation rate within the flow of two immiscible micropolar fluids in a horizontal channel bounded by two porous beds at the bottom and top. The flow is considered in four zones. Zone IV contains the flow of viscous fluid in the large porous bed at the bottom, zone I and zone II contain the free flow of...

An attempt has been made to study the entropy generation analysis of couple stress fluid flow in an annulus between two concentric rotating vertical cylinders. There is a porous lining attached to the inside of an outer cylinder. The flow is under the influence of a radial magnetic field. The flow in the annular gap is caused by rotation of the cyl...

The paper deals with the flow of two immiscible couple stress fluids between two homogeneous permeable beds. The flow is considered in two zones: zone I and II contain free flow of two immiscible couple stress fluids between two permeable porous beds at the bottom and top. The flow in the free channel bounded by two permeable beds is assumed to be...

The flow of an incompressible micro-polar fluid generated due to rectilinear oscillations of a sphere about a diameter of the sphere is considered. The flow is so slow that oscillations Reynolds number is less than unity and hence nonlinear convective terms in the equations of motion are neglected. A rare but distinct special case in which material...

Stokes viscous flow past a partially contaminated fluid sphere with no slip condition is considered. No mass transfer for the entire sphere, no slip condition on contaminated part, shear stress continuity on clear part and regularity condition at far away from the body are considered for boundary conditions for evaluation of stream function.

This paper investigates the entropy generation analysis in a steady flow of two immiscible couple stress fluids in a horizontal channel bounded by two porous beds at the bottom and top. The flow is considered in four zones: zone IV contains the flow of viscous fluid in the large porous bed with low permeability at the bottom, zones I and II contain...

The paper aims the heat transfer analysis for the flow of two immiscible micropolar fluids inside a horizontal channel, by the first and second laws of thermodynamics under the action of an imposed transverse magnetic field. The plates of the channel are maintained at constant temperatures higher than that of the fluid. The flow region consists of...

In this Paper, the flow generated by the slow steady rotation of a permeable sphere with thin surface about its axis of symmetry in an incompressible couple stress fluid which is otherwise at rest is studied. Expressions for the velocity and couple stress tensor components are obtained in terms of modified Bessel functions and Gagenbauer’s polynomi...

This paper aims to analyze the heat transfer by the first and second laws of thermodynamics for the flow of two immiscible couple stress fluids inside a horizontal channel under the action of an imposed transverse magnetic field. The plates of the channel are maintained at constant and different temperatures higher than that of the fluid. The flow...

The flow generated by a circular cylinder, performing longitudinal and torsional oscillations, in an infinite expanse of a micropolar fluid is studied. Analytical expressions for the velocity and micro rotation components are obtained using no slip and hyper stick conditions at the boundaries. The effects of coupling number; Reynolds number and gyr...

The article deals with the flow of two immiscible incompressible micropolar fluids between two homogeneous porous beds at the bottom and top when the beds are of (A) infinite thickness and (B) finite thickness. The flow of two immiscible micropolar fluids is considered in two zones (zone II and zone III). This flow is bounded by zone I at the botto...

In this paper we consider the incompressible micropolar fluid flow between two parallel plates, generated due to periodic suction and injection at the plates. The flow field and pressure are considered as periodic functions expanded in terms of Reynolds number of the flow and exp(iwnt). The problem is analyzed up to first order flow. The case of co...

The flow of a couple stress fluid generated by performing longitudinal and torsional oscillations of a porous circular cylinder subjected to constant suction at the surface of the cylinder is studied. A finite difference method is proposed to analyze the velocity components, in an infinite expanse of an incompressible couple stress fluid under vani...

In this paper, the problem of steady Poiseuille flow of two immiscible incompressible micropolar fluids between two horizontal parallel plates of a channel with constant wall temperatures is studied in terms of entropy generation. The flow is assumed to be governed by Eringen’s micropolar fluid flow equations. The flow region is divided into two zo...

The flow generated by performing longitudinal and torsional oscillations of a porous circular cylinder which is subjected to constant suction/injection at the surface of the porous cylinder is studied. A finite difference method is proposed to analyse the velocity components and micro-rotation components, in an infinite expanse of an incompressible...

The flow generated by performing longitudinal and torsional oscillations of a porous circular cylinder which is subjected to constant suction/injection at the surface of the porous cylinder is studied. A finite difference method is proposed to analyse the velocity components and micro-rotation components, in an infinite expanse of an incompressible...

The flow generated by performing longitudinal and torsional oscillations of a porous circular cylinder which is subjected to constant suction/injection at the surface of the porous cylinder is studied. A finite difference method is proposed to analyze the velocity components and micro-rotation components, in an infinite expanse of an incompressible...

In this paper, the steady flow of an incompressible conducting micropolar fluid through a rectangular channel with uniform cross-section in the presence of a transverse magnetic field with suction and injection at the side walls is considered. Neglecting the induced magnetic and electric fields, velocity and micro-rotation vectors are obtained in t...

The flow of micropolar fluid inside a circular cylinder that is subjected to longitudinal and torsional oscillations with different frequencies is investigated. Analytical expressions for the velocity components and microrotation components are obtained in terms of modified Bessel's functions. The drag force acting on the wall of the cylinder is de...

In this paper, we consider the flow of an incompressible micropolar fluid past a permeable sphere. The flow pattern for the outer and inner regions is obtained in terms of stream function under the boundary conditions: (i) continuity of normal velocity on the sphere, (ii) vanishing of tangential velocity on the sphere and (iii) zero micro-rotati...

The steady flow of incompressible micropolar fluid flow through a rectangular channel is considered assuming a constant pressure gradient. The governing partial differential equations are solved numerically using finite difference method. The effects of geometric and micropolar parameters on the velocity and microrotation are discussed.

In this paper, we consider the unsteady flow of an incompressible electrically conducting micropolar fluid through a circular porous pipe subjected to periodic suction/injection at the walls of the tube and in the presence of a transverse magnetic field. Under the Stokesian assumption and using the similarity transformations, the stream function an...

The flow generated by a circular cylinder, performing longitudinal and torsional oscillations, in an infinite expanse of couple stress fluid is studied. Analytical expressions for the velocity components are obtained under vanishing couple stresses of type A condition or super adherence condition of type B on the boundary. The effects of couple str...

We study the slow steady flow of an incompressible couple stress fluid past a permeable sphere with thin surface. The flow pattern (stream function) for the outer and inner regions is obtained. The effects of permeability parameter and geometric parameter on the drag are studied numerically. The corresponding results are presented in the form of gr...

We study an incompressible viscous fluid flow and temperature distribution between two parallel plates, generated due to periodic suction suction and injection at the plates. The flow field, pressure and temperature are assumed to be periodic functions and are expanded in terms of suction Reynolds number. The problem is analyzed up to second order....

In this paper we consider the incompressible viscous fluid flow between two parallel plates, generated due to periodic suction and injection at the plates. The flow field and pressure are considered as periodic functions expanded in terms of Reynolds number of the flow and exp(iwnt). The problem is analyzed up to second order flow. Various cases li...

A mathematical model to describe the drying characteristics of solids in a continuous fluidized bed dryer has been developed. The RTD model proposed by Pydi Setty et al. 1 is used to obtain the required drying model. Experimental data in a continuous fluidized bed dryer are satisfactorily matched with the model developed. Using the model, one can p...

The problem of viscous fluid past an axisymmetric body embedded in a fluid saturated porous medium is studied using the Brinkman's extension. A general formula for the drag on the body is derived in the form of a limit of an expression involving the stream function characterizing the flow. The flow past an axisymmetric approximate sphere is also co...

In this paper, we consider the unsteady flow of incompressible micropolar fluid between two parallel porous plates when there is a periodic suction at the lower plate and injection at the upper plate. Stream function for the flow is obtained and the effects of microrotation parameter and frequency parameter on skin friction at the lower and upper p...

The slow steady rotation of a viscous liquid bounded by concentric spheroid (of small ellipticity) and sphere rotating with different angular velocities about two different axes has been studied. Due to the linear nature of the problem, the complete solution is obtained as a superposition of two motions: in each of which one body is rotating while...

An elliptic cylinder is performing oscillations parallel to either of the principal axes of the cross-sectional ellipse in a fluid particle suspension. The stream function governing the flow and the velocity components are determined in terms of Mathieu functions. The drag on the cylinder is evaluated and expressed in terms of two parametersK andK....