Sonam Singh | IIT Roorkee (original) (raw)

Papers by Sonam Singh

In the present study, a numerical analysis is carried out to investigate unsteady MHD (magneto-hy... more In the present study, a numerical analysis is carried out to investigate unsteady MHD (magneto-hydrodynamic) flow and heat transfer of a non-Newtonian second grade viscoelastic fluid over an oscillatory stretching sheet. The flow is induced due to an infinite elastic sheet which is stretched oscillatory (back and forth) in its own plane. Effect of viscous dissipation and joule heating are taken into account. The non-linear differential equations governing the problem are transformed into system of non-dimensional differential equations using similarity transformations. A newly developed meshfree numerical technique Element free Galerkin method (EFGM) is employed to solve the coupled non linear differential equations. The results illustrating the effect of various parameters like viscoelastic parameter, Hartman number, relative frequency amplitude of the oscillatory sheet to the stretching rate and Eckert number on velocity and temperature field are reported in terms of graphs and ta...

In this article we examine numerically the unsteady squeezing hydrodynamics of an electrically-co... more In this article we examine numerically the unsteady squeezing hydrodynamics of an electrically-conducting micropolar lubricant between two parallel plates in the presence of a uniform strength magnetic field. The governing partial differential equations are transformed into non-dimensional, nonlinear coupled ordinary differential equations for translational and angular momentum (micro-inertia). These equations are solved numerically using the Element Free Galerkin Method (EFGM). Excellent accuracy is achieved. The influence of magnetic field parameter (Ha), micropolar spin gradient viscosity parameter (), Eringen vortex viscosity parameter (R) and unsteadiness parameter (S) on linear and angular velocity (microrotation) are presented graphically. The excellent potential of EFGM in bio-lubrication flows is highlighted.

In this paper, the mixed convection magneto-hydrodynamic (MHD) flow along a vertical semi-infinit... more In this paper, the mixed convection magneto-hydrodynamic (MHD) flow along a vertical semi-infinite power-law stretching sheet has been examined. The velocity and temperature of the sheet are assumed to vary in power-law form. A magnetic field of uniform strength is applied normal to the surface. The differential equations governing the problem have been transformed by a similarity transformation into a system of non-dimensional differential equations which are solved numerically by Element Free Galerkin Method (EFGM). The influence of buoyancy parameter, exponent parameter, ratio of free stream velocity to the composite reference velocity, magnetic parameter on the velocity, temperature, local skin friction and local heat transfer are explained and shown graphically. Such type of problems have numerous applications in many engineering manufacturing processes as wire and fiber coating, cooling of metallic sheets or electronic chips, drawing of plastic sheets etc.

The Scientific World Journal, 2014

This paper presents a numerical study of natural convection within a wavy enclosure heated via co... more This paper presents a numerical study of natural convection within a wavy enclosure heated via corner heating. The considered enclosure is a square enclosure with left wavy side wall. The vertical wavy wall of the enclosure and both of the corner heaters are maintained at constant temperature,TcandTh, respectively, withTh>Tcwhile the remaining horizontal, bottom, top and side walls are insulated. A penalty element-free Galerkin approach with reduced gauss integration scheme for penalty terms is used to solve momentum and energy equations over the complex domain with wide range of parameters, namely, Rayleigh number (Ra), Prandtl number (Pr), and range of heaters in thex- andy-direction. Numerical results are represented in terms of isotherms, streamlines, and Nusselt number. It is observed that the rate of heat transfer depends to a great extent on the Rayleigh number, Prandtl number, length of the corner heaters and the shape of the heat transfer surface. The consistent performa...

International Journal of Numerical Methods for Heat & Fluid Flow, 2015

Purpose – The purpose of this paper is to study the flow and heat transfer characteristics of a p... more Purpose – The purpose of this paper is to study the flow and heat transfer characteristics of a phase transition, melting problem. In this problem, phase transition between solid and liquid takes place within a square enclosure in the presence of natural convection. Design/methodology/approach – The physical problem, described with non-linear partial differential equations, is simulated using a hybrid finite element and element free Galerkin method (FEM/EFGM) approach. In energy conservation equation, the fixed-domain, effective heat capacity method is used to take into account the latent heat of phase change. The governing partial differential equations are solved with a meshfree, EFGM near the phase transition front while in the region away from the front with uniform nodal distribution; problem is simulated with traditional FEM. Findings – A sensitivity analysis of characteristic dimensionless numbers Rayleigh number (Ra), Prandtl number (Pr), Stefan number (ste) is presented in ...

Journal of Heat Transfer, 2014

In medical world, the minimally invasive freezing therapy or cryosurgery is an efficacious treatm... more In medical world, the minimally invasive freezing therapy or cryosurgery is an efficacious treatment for complete and controlled eradication of tumor cells. Many difficulties are encountered in cryosurgery process such as inappropriate freezing may not completely destroy the target tumor tissue and excessive freezing may harm the surrounding healthy tissues due to release of high amount of cold from the freezing probe. In present study, the target tumor tissue is loaded with nanoparticles in order to improve the freezing capacity of probe and to regulate the orientation and size of ice-ball formed during cryosurgery. In this process, phase transformation occurs in the undesired tumor tissues. For simulation of phase transition in bio heat transfer equation, the fixed-domain, heat capacity method is used to take into account the latent heat of phase change. In this study, a meshfree numerical technique known as element free Galerkin method (EFGM) is employed to simulate the phase tra...

2013 International Conference on Advances in Computing, Communications and Informatics (ICACCI), 2013

This paper demonstrates the power of one of the recent but strong computing method for solving or... more This paper demonstrates the power of one of the recent but strong computing method for solving ordinary partial differential equations (ODE) & partial differential equations (PDE). Many mathematical models are governed by differential equations and hence due to large data involved, the only possible solution is numerical solution. The basic features of the meshfree methods with special reference to Element free Galerkin method (EFGM) has been presented here. To show its efficiency, one problem as a case study on heat transfer has been solved using this technique. In this problem, unsteady, laminar boundary layer flow of an incompressible, viscous and electrically conducing fluid over a horizontal stretching sheet is considered and governing non-linear partial differential equations are solved with element free galerkin method. The impact of various parameters used in element free galerkin method like penalty parameter, scaling parameter and different weigh functions on obtained velocity and temperature profiles is discussed in detail.

Purpose – The purpose of this paper is to study the flow and heat transfer characteristics of a p... more Purpose – The purpose of this paper is to study the flow and heat transfer characteristics of a phase transition, melting problem. In this problem, phase transition between solid and liquid takes place within a square enclosure in the presence of natural convection.
Design/methodology/approach – The physical problem, described with non-linear partial differential equations, is simulated using a hybrid finite element and element free Galerkin method (FEM/EFGM) approach. In energy conservation equation, the fixed-domain, effective heat capacity method is used to take into account the latent heat of phase change. The governing partial differential equations are solved with a meshfree, EFGM near the phase transition front while in the region away from the front with uniform nodal distribution; problem is simulated with traditional FEM.

In medical world, the minimally invasive freezing therapy or cryosurgery is an efficacious treatm... more In medical world, the minimally invasive freezing therapy or cryosurgery is an efficacious
treatment for complete and controlled eradication of tumor cells. Many difficulties are
encountered in cryosurgery process such as inappropriate freezing may not completely
destroy the target tumor tissue and excessive freezing may harm the surrounding healthy
tissues due to release of high amount of cold from the freezing probe. In present study,
the target tumor tissue is loaded with nanoparticles in order to improve the freezing
capacity of probe and to regulate the orientation and size of ice-ball formed during cryosurgery.
In this process, phase transformation occurs in the undesired tumor tissues. For
simulation of phase transition in bio heat transfer equation, the fixed-domain, heat
capacity method is used to take into account the latent heat of phase change. In this
study, a meshfree numerical technique known as element free Galerkin method (EFGM)
is employed to simulate the phase transition and temperature field for a biological tissue
subjected to nanocryosurgery. The latest nanofluid model which includes the effects of
particles size, concentration, and the interfacial layer at the particle/liquid interface is
utilized and their impact on freezing process is investigated in detail.

This paper presents a numerical study of natural convection within a wavy enclosure heated via co... more This paper presents a numerical study of natural convection within a wavy enclosure heated via corner heating. The considered enclosure is a square enclosure with left wavy side wall. The vertical wavy wall of the enclosure and both of the corner heaters are maintained at constant temperature, and ℎ , respectively, with ℎ > while the remaining horizontal, bottom, top and side walls are insulated. A penalty element-free Galerkin approach with reduced gauss integration scheme for penalty terms is used to solve momentum and energy equations over the complex domain with wide range of parameters, namely, Rayleigh number (Ra), Prandtl number (Pr), and range of heaters in the -and -direction. Numerical results are represented in terms of isotherms, streamlines, and Nusselt number. It is observed that the rate of heat transfer depends to a great extent on the Rayleigh number, Prandtl number, length of the corner heaters and the shape of the heat transfer surface. The consistent performance of the adopted numerical procedure is verified by comparison of the results obtained through the present meshless technique with those existing in the literature.

The unsteady squeezing hydrodynamics of a Micropolar lubricant between two parallel plates is inv... more The unsteady squeezing hydrodynamics of a Micropolar lubricant between two parallel plates is investigated. The partial differential equations describing the two-dimensional flow regime are transformed into non-dimensional, nonlinear coupled ordinary differential equations for linear and angular momentum (micro-inertia). These equations are solved using the robust EFGM (Element Free Galerkin Method). Excellent accuracy is achieved. The influence of micropolar spin gradient viscosity parameter (G), Eringen vortex viscosity parameter (R) and unsteadiness parameter (S) on linear and angular velocity (micro-rotation) and couple stress are presented graphically. The excellent potential of EFGM in bio-lubrication flows is highlighted.

The Scientific World Journal, 2014

International Journal of Numerical Methods for Heat & Fluid Flow, 2015

Journal of Heat Transfer, 2014

2013 International Conference on Advances in Computing, Communications and Informatics (ICACCI), 2013

Purpose – The purpose of this paper is to study the flow and heat transfer characteristics of a p... more Purpose – The purpose of this paper is to study the flow and heat transfer characteristics of a phase transition, melting problem. In this problem, phase transition between solid and liquid takes place within a square enclosure in the presence of natural convection.
Design/methodology/approach – The physical problem, described with non-linear partial differential equations, is simulated using a hybrid finite element and element free Galerkin method (FEM/EFGM) approach. In energy conservation equation, the fixed-domain, effective heat capacity method is used to take into account the latent heat of phase change. The governing partial differential equations are solved with a meshfree, EFGM near the phase transition front while in the region away from the front with uniform nodal distribution; problem is simulated with traditional FEM.

In medical world, the minimally invasive freezing therapy or cryosurgery is an efficacious treatm... more In medical world, the minimally invasive freezing therapy or cryosurgery is an efficacious
treatment for complete and controlled eradication of tumor cells. Many difficulties are
encountered in cryosurgery process such as inappropriate freezing may not completely
destroy the target tumor tissue and excessive freezing may harm the surrounding healthy
tissues due to release of high amount of cold from the freezing probe. In present study,
the target tumor tissue is loaded with nanoparticles in order to improve the freezing
capacity of probe and to regulate the orientation and size of ice-ball formed during cryosurgery.
In this process, phase transformation occurs in the undesired tumor tissues. For
simulation of phase transition in bio heat transfer equation, the fixed-domain, heat
capacity method is used to take into account the latent heat of phase change. In this
study, a meshfree numerical technique known as element free Galerkin method (EFGM)
is employed to simulate the phase transition and temperature field for a biological tissue
subjected to nanocryosurgery. The latest nanofluid model which includes the effects of
particles size, concentration, and the interfacial layer at the particle/liquid interface is
utilized and their impact on freezing process is investigated in detail.

This paper presents a numerical study of natural convection within a wavy enclosure heated via co... more This paper presents a numerical study of natural convection within a wavy enclosure heated via corner heating. The considered enclosure is a square enclosure with left wavy side wall. The vertical wavy wall of the enclosure and both of the corner heaters are maintained at constant temperature, and ℎ , respectively, with ℎ > while the remaining horizontal, bottom, top and side walls are insulated. A penalty element-free Galerkin approach with reduced gauss integration scheme for penalty terms is used to solve momentum and energy equations over the complex domain with wide range of parameters, namely, Rayleigh number (Ra), Prandtl number (Pr), and range of heaters in the -and -direction. Numerical results are represented in terms of isotherms, streamlines, and Nusselt number. It is observed that the rate of heat transfer depends to a great extent on the Rayleigh number, Prandtl number, length of the corner heaters and the shape of the heat transfer surface. The consistent performance of the adopted numerical procedure is verified by comparison of the results obtained through the present meshless technique with those existing in the literature.