Hydrodynamic and hydromagnetic stability

Thermal-diffusion and diffusion-thermo effects on mixed free-forced convective and mass transfer boundary layer flow with temperature dependent viscosity

This work is focused on the numerical solution of steady natural convection boundary-layer flow of a nanofluid consisting of a pure fluid with nanoparticles along a permeable vertical plate in the presence of magnetic field, heat generation or absorption, and suction or injection effects The model used for the nanofluid incorporates the effects of Brownian motion and thermophoresis The governing boundary-layer equations of the problem are formulated and transformed into a non-similar form The obtained equations are then solved numerically by an efficient, iterative, tri-diagonal, implicit finite-difference method Comparisons with previously published work are performed and are found to be in excellent agreement Representative results for the longitudinal velocity, temperature, and nanoparticle volume fraction profiles as well as the local heat transfer rates for various values of the physical parameters are displayed in both graphical and tabular forms

Mhd free convection flow of a nanofluid past a vertical plate in the presence of heat generation or absorption effects

Non-uniform heat source/sink and Soret effects on MHD non-Darcian convective flow past a stretching sheet in a micropolar fluid with radiation

The problem of combined free-forced convection and mass transfer flow over a vertical porous flat plate, in presence of heat gene ration and thermal- diffusion, is studied numerically. The non-linear partial differential equations and their boundary conditions, describing the problem under consideration, are transformed into a system of ordinary differential equatio ns by using usual similarity transformations. This system is solved numerically by applying Nachtsheim-Swigert shooting iteration technique together with Runge-Kutta sixth order integration scheme. The effects of suction parameter, heat generation parameter and Soret number are examined on the flow field of a hy drogen-air mixture as a non-chemical reacting fluid pair. The analysis o f the obtained results showed that the flow field is significantly influenced b y these parameters.

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Numerical Study of the Combined Free-Forced Convection and Mass Transfer Flow Past a Vertical Porous Plate in a Porous Medium with Heat Generation and Thermal Diffusion

An analytical study is performed to examine the free-convection and mass transfer flow for the Sokes problem for an infinite vertical plate on taking into account the Soret effect (thermal diffusion effect). The Laplace transform technique is used to obtain the expressions for velocity and skin-friction. The effect of Soret numberS on velocity field and skin-friction is extensively discussed with the help of graphs and table.

Soret effects on free-convection and mass transfer flow in the stokes problem for a infinite vertical plate

The paper is based on the ionospheric variations in terms of vertical total electron content (VTEC) for the low solar activity period from May 2007 to April 2009 based on the analysis of dual frequency signals from the Global Positioning System (GPS) satellites recorded at ground stations Varanasi (Geographic latitude 25°16′ N, Longitude 82°59′ E), situated near the equatorial ionization anomaly crest and other two International GNSS Service (IGS) stations Hyderabad (Geographic latitude 17°20′ N, longitude 78°30′ E) and Bangalore (Geographic latitude 12°58′ N, longitude 77°33′ E) in India. We describe the diurnal and seasonal variations of total electron content (TEC), and the effects of a space weather related event i.e. a geomagnetic storm on TEC. The mean diurnal variation during different seasons is brought out. It is found that TEC at all the three stations is maximum during equinoctial months (March, April, September and October), and minimum during the winter months (November, December, January and February), while obtaining intermediate values during summer months (May, June, July and August). TEC shows a semi-annual variation. TEC variation during geomagnetic quiet as well as disturbed days of each month and hence for each season from May 2007 to April 2008 at Varanasi is examined and is found to be more during disturbed period compared to that in the quiet period. Monthly, seasonal and annual variability of GPS-TEC has been compared with those derived from International Reference Ionosphere (IRI)-2007 with three different options of topside electron density, NeQuick, IRI01-corr and IRI 2001. A good agreement is found between the GPS-TEC and IRI model TEC at all the three stations.

https://www.tpbin.com/Uploads/Subjects/1f62debb-05f5-4eca-aa3a-9d9bbf98c645.pdf

GPS-TEC variations during low solar activity period (2007–2009) at Indian low latitude stations

The flow past an infinite vertical isothermal plate started impulsively in its own plane in a viscous incompressible and electricalfy conducting fluid has been presented in a rotating system. The magnetic Reynolds number is assumed small so that the induced magnetic field can be neglected. The governing equations of the flow are solved by defining a complex variable with the help of the Laplace transform technique. The influence of the various parameters, occurring into the problem, on the axial and transverse components of the velocity and skin-friction is extensively discussed with the help of graphs and table.

MHD free-convection flow in the stokes problem for a vertical porous plate in a rotating system

The effect of a uniform transverse magnetic field on the free-convection flow of an electrically conducting fluid past a uniformly accelerated infinite vertical porous plate is discussed. Finite-difference method has been used to obtain the solution of the governing equations when the Prandtl number is not equal to unity. The velocity profiles have been shown graphically for both cases, cooling and heating of the porous plate. The numerical values of the skin-friction are entered in table and the effects of the various parameter are discussed on the flow field.

Finite difference analysis of MHD free-convection flow past an accelerated vertical porous plate

Hall effects on the hydromagnetic free convection flow of an electrically conducting incompressible viscous fluid past a steadily moving vertical porous plate has been analysed when the free stream oscillates in magnitude. The flow is subjected to a constant suction, through the porous plate, and the difference between wall temperature and the free-stream is moderately large causing the free convection currents. The mathematical analysis is presented for the hydromagnetic boundary layer flow without taking into account the induced magnetic field. This is a valid assumption for small magnetic Reynolds number. Approximate solutions for the components of velocity field and temperature field and their related quantities are obtained. The influence of various parameters entering into the problem is extensively discussed with the help of graphs and tables.

A. K. Singh

Papers

Soret effects on free-convection and mass transfer flow in the stokes problem for a infinite vertical plate

GPS-TEC variations during low solar activity period (2007–2009) at Indian low latitude stations

MHD free-convection flow in the stokes problem for a vertical porous plate in a rotating system

Finite difference analysis of MHD free-convection flow past an accelerated vertical porous plate

Hall effects on the oscillatory MHD flow in the stokes problem past an infinite vertical porous plate, II