The thermodynamic second law analysis is utilized to investigate the inherent irreversibility in an unsteady hydromagnetic generalized Couette flow with variable electrical conductivity in the presence of induced electric field. Based on some simplified assumption, the model nonlinear governing equations are obtained and solved numerically using semidiscretization finite difference techniques. ...

We prove that smooth solutions of non-ideal (viscous and resistive) incompressible magnetohydrodynamic equations satisfy a stochastic law of flux conservation. This property involves an ensemble of surfaces obtained from a given, fixed surface by advecting it backward in time under the plasma velocity perturbed with a random white-noise. It is shown that the magnetic flux through the fixed surf...

A review is made of recent magnetohydrodynamic (MHD) theory and simulations of origin of jets from accretion disks. Many compact astrophysical objects emit powerful, highly-collimated, oppositely directed jets. Included are the extra galactic radio jets of active galaxies and quasars, and old compact stars in binaries, and emission line jets in young stellar objects. It is widely thought that t...

A modified version of Chandrasekhar's equation is derived with the aid of Karman 's energy transfer process for the decay of hydromagnetic turbulence in the limiting case of zero viscosity and infinite electrical conductivity. I t is found that the asymptotic behaviour of self-preserving solutions of the aforesaid equations leads to F(k, t) m k4, (c = 2/7), G(k, t) fa k6, (c = 2/9) as and F(k,t...

Direct evidence for the presence of an inertial energy cascade, the most characteristic signature of hydromagnetic turbulence (MHD), is observed in the solar wind by the Ulysses spacecraft. After a brief rederivation of the equivalent of Yaglom's law for MHD turbulence, a linear relation is indeed observed for the scaling of mixed third-order structure functions involving Elsässer variables. Th...

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This paper investigates the steady hydromagnetic three-dimensional boundary layer flow of Maxwell fluid over a bidirectional stretching surface. Both cases of prescribed surface temperature (PST) and prescribed surface heat flux (PHF) are considered. Computations are made for the velocities and temperatures. Results are plotted and analyzed for PST and PHF cases. Convergence analysis is present...

Time-dependent hydromagnetic phenomena in a rotating spherical cavity are investigated in the framework of an interior boundary-layer expansion. The interior problem is shown to contain waves whose frequencies are of order o, A o and A2u, where w is the rotation rate of the cavity and A2 = B2/4npu2R2 < 1 is the Alfven number. B is an imposed magnetic field, p the fluid density and R the radius ...

Evidence accumulated over the past several decades indicates that a large-scale applied (dc) magnetic field imposes a preferred direction on turbulence, and thus plays an important role in plasma diffusion [1], energetic particle scattering [2], and plasma heating [3–5]. Each of these in turn may significantly influence large-scale flows and structure [6–8]. The interplay between turbulence and...

The stability properties of newly born neutron stars, or proto–neutron stars (PNSs), are considered. We take into account dissipative processes, such as neutrino transport and viscosity, in the presence of a magnetic field. In order to find the regions of the star subject to different sorts of instability, we derive the general instability criteria and apply it to evolutionary models of PNSs. T...