MHD

Aqueous extracts, prepared from dried or fresh roots, stems or leaves of Mikania glomerata, a plant found in Mata Atlântica in Southeastern Brazil, were able to efficiently neutralize different toxic, pharmacological, and enzymatic effects induced by venoms from Bothrops and Crotalus snakes. Phospholipase A2 activity and the edema induced by Crotalus durissus terrificus venom were inhibited around 100 and ∼40%, respectively, although this inhibition was only partial for Bothrops venoms. The hemorrhagic activity of Bothrops venoms (Bothrops altenatus, Bothrops moojeni, Bothrops neuwiedi, and Bothrops jararacussu) was significantly inhibited by this vegetal species, while the clotting activity of Crotalus durissus terrificus, Bothrops jararacussu, and Bothrops neuwiedi venoms was totally inhibited. Although, the mechanism of action of Mikania glomerata extract is still unknown, the finding that no visible change was detected in the electrophoretic pattern of snake venom after incubation with the extract excludes proteolytic degradation as a potential mechanism. Since the extract of Mikania glomerata significantly inhibited the studied snake venoms, it may be used as an alternative treatment to serumtherapy and, in addition, as a rich source of potential inhibitors of PLA2s, metalloproteases and serineproteases, enzymes involved in several physiopathological human and animal diseases.

The study of MHD and nano effect on the flow over a moving surface in presence
of thermal radiation, vis
Engineering processes can be modeled as flow over a moving surface. Viscous
nanofluid flows play very important role in chemical engineering. So in this paper the
effect of viscous dissipation and chemi
layer region is studied. The governing equations are solved by HAM by considering
plate movement in both the directions. The effects of non
graphically represented and the results

Abstract
Purpose – The purpose of this study is numerical simulation of magnetohydrodynamics (MHD) water–
Al2O3 nanofluid mixed convection in a grooved channel with internal heat generation in solid cylinders.
Simulations were carried out at Reynolds numbers 50#Re#100, Hartmann numbers 0#Ha#15, Grashof
numbers 5,000#Gr#10
4 and volume fraction 0#w #0.04. The effect of Reynolds number and the
influence of magnetic field and pressure drop on convective heat transfer coefficient were studied in different
volume fractions of nanoparticles at different Reynolds numbers.
Design/methodology/approach – The results show that average Nusselt number increases by
increasing Reynolds and Hartman numbers. Also, when Hartman number increases, velocity profile becomes
asymmetric. Pressure distribution shows that magnetic field applies Lorentz force at opposite direction of the
flow, which causes asymmetric distribution of pressure. As a result, pressure in the upper half of the cylinder
is higher than the lower half. Finally, velocity and temperature contours along the channel for different
Hartmann numbers, volume fraction 3 per cent, Re = 50 and 100 and Gr = 10,000, are presented.
Findings – The effect of Reynolds number and the influence of magnetic field and pressure drop on convective
heat transfer coefficientwere studied in different volume fractions of nanoparticles at different Reynolds numbers.
Originality/value – Effect of MHD on the flow and heat transfer characteristics of Water–Al2O3 nanofluid
in a grooved channel with internal heat generation in solid cylinders.

The steady two-dimensional flow of an incompressible non-Newtonian Molybdenum Disulfide nanofluid in the presence of source or sink between two stretchable or shrinkable walls under the influence of thermal radiation is investigated numerically. A generalized transformation is applied to convert the constructed set of partial differential equations (PDEs) into the system of non-linear coupled ordinary differential equations (ODEs). The obtained system of ODEs is solved by using Runge-Kutta 4 th and 5 th order. The influence of physical parameters, shrinking/ stretching parameter, Casson parameter, Hartmann number, Reynolds number, solid volume fraction, opening angle of the channel and radiation parameter on the velocity and temperature distribution are observed for converging and diverging channels. It is noticed that thermal boundary layer thickness is diminished for increased thermal radiation resulting in gradual temperature fall. The results also reveal that velocity and temperature profile both are elevated on raising the stretching parameter and Hartmann number. A comparative analysis is made out to validate the present results.

Numerical investigation is carried out to analyze the flow, heat and mass transfer characteristics of gyrotactic microorganisms contained magneto hydrodynamic Casson fluid flow towards a vertical rotating cone/plate in porous medium. In the presence of thermo diffusion and diffusion thermo effects we have presented dual solutions for the flow over a rotating cone and a rotating flat plate. Further, the numerical solutions are elucidated by using Runge–Kutta–Felhberg integration Scheme. Obtained results are validated with open literature and found an excellent agreement. The influence of non-dimensional governing parameters on velocity, temperature, concentration and density of the motile microorganisms along with the friction factor, local Nusselt, Sherwood numbers and the local density of the motile microorganisms was determined and discussed with the help of graphs and tables. Results proved that there is a significant variation of heat and mass transfer in the flow over a rotating cone and a plate. It is also found that the heat and mass transfer performance of the flow over a rotating cone is significantly high while compared with the flow over a rotating plate.

In this paper the problem of two dimensional, unsteady, laminar, magneto hydro
dynamic free convective flow through a porous medium past a vertical plate in the
presence of heat absorption and chemical reaction is considered. The Dufour effect is
taken into account. The free stream velocity is supposed to follow the exponentially
increasing small perturbation law. The non-dimensional governing equations are
solved analytically by two-term harmonic and non-harmonic functions. The velocity,
temperature and concentration distributions are analyzed for different values of
parameters

This paper presents an analysis of combined heat and mass transfer MHD flow past an oscillating vertical porous plate under the action of radiation effects and chemical reaction when heat is supplied to the plate at constant rate. The governing equations are solved in two term perturbation method. The results are obtained for velocity, temperature, concentration, skin friction, Nusselt number and Sherwood number. The effects of various parameters on flow variables are illustrated graphically, and the physical aspects of the problem are discussed qualitatively.

This research article explores on the steady of the two-dimensional buoyancy effects on MHD Casson fluid flow over a stretching of permeable sheet through a porous medium in the occurrence of suction/injection. The central PDEs are changed into ODEs by applying similarity transformations and the changed equations’ solutions are got by Runge-Kutta fourth order along with a shooting technique. The working fluid flow is considered for numerous different parameters graphically. It has been observed that velocity decreases, temperature and concentration increase when magnetic field and permeability of porous parameter increases

In this paper the problem of two dimensional, unsteady, laminar, magneto hydro
dynamic free convective flow through a porous medium past a vertical plate in the
presence of heat absorption and chemical reaction is considered. The Dufour effect is
taken into account. The free stream velocity is supposed to follow the exponentially
increasing small perturbation law. The non-dimensional governing equations are
solved analytically by two-term harmonic and non-harmonic functions. The velocity,
temperature and concentration distributions are analyzed for different values of
parameters.

In this paper, the unsteady magneto hydrodynamic flow past an oscillating vertical plate under the influence of Soret and Dufour effects has been investigated. The nonlinear partial differential equations governing the flow are solved by an iterative technique based on finite difference scheme. The flow phenomenon is characterized with the help of velocity, temperature and concentration profiles for different parameters.

ABSTRACT In this paper we analyzed the effect of magnetic field on stagnation point flow and heat transfer due to nanofluid towards a stretching sheet. The transport equations employed in the analysis include the effect of Brownian motion and thermophoresis. The solution for the temperature and nanoparticle concentration depends on six parameters viz. velocity ratio parameter A, Prandtl number Pr, Lewis number Le, Brownian motion Nb, and the thermophoresis parameter Nt. Similarity transformation is used to convert the governing nonlinear boundary-layer equations to coupled higher order nonlinear ordinary differential equation. These equations were numerically solved using Runge–Kutta fourth order method with shooting technique. Numerical results are obtained for velocity, temperature and concentration distribution, as well as the skin friction coefficient, local Nusselt number and Sherwood number. The results indicate that the skin friction coefficient Cf and local Nusselt number increases with an increase in velocity ratio parameter A. Likewise, the local Sherwood number increases with an increase in both velocity ratio A and Lewis number Le. Besides, it is found that the heat transfer rate at the surface increases with the magnetic parameter when the free stream velocity exceeds the stretching velocity, i.e. A > 1, and it decreases when A < 1. A comparison with a previous study available in the literature has been done and we found an excellent agreement with them.

The effects of heat and mass transfer on MHD mixed convection flow of a vertical surface with radiation, heat source/absorption and chemical reaction has been is discussed. The resulting set of coupled non-linear ordinary differential equations is solved by perturbation technique and for graphs we used MATLAB software. Approximate solutions have been derived for the velocity, temperature, concentration profiles, skin friction and Nusselt number. The obtained results are discussed with the help of the graphs to observe the effect of various parameters like Grashof number, modified Grashof number, Schmidt number, Prandtl number, Magnetic parameter, Radiation parameter, Chemical reaction, Heat source parameter, Radiation absorption parameter.

Helicity and \alpha effect driven by the nonaxisymmetric Tayler instability of toroidal magnetic fields in stellar radiation zones are computed. In the linear approximation a purely toroidal field always excites pairs of modes with identical growth rates but with opposite helicity so that the net helicity vanishes. If the magnetic background field has a helical structure by an extra (weak)

We present a five-wave Riemann solver for the equations of ideal relativistic magneto-hydrodynamics. Our solver can be regarded as a relativistic extension of the five-wave HLLD Riemann solver initially developed by Miyoshi & Kusano for the equations of ideal magnetohydrodynamics. The solution to the Riemann problem is approximated by a five-wave pattern, comprising two outermost fast shocks, two rotational discontinuities and a contact surface in the middle. The proposed scheme is considerably more elaborate than in the classical case since the normal velocity is no longer constant across the rotational modes. Still, proper closure to the Rankine-Hugoniot jump conditions can be attained by solving a non-linear scalar equation in the total pressure variable which, for the chosen configuration, has to be constant over the whole Riemann fan. The accuracy of the new Riemann solver is validated against one-dimensional tests and multidimensional applications. It is shown that our new solver considerably improves over the popular Harten-Lax-van Leer solver or the recently proposed HLLC schemes.