In this paper, the problem of unsteady mixed convection boundary layer flow of a viscous incompressible fluid near the stagnation-point on a vertical permeable plate with both cases of prescribed wall temperature and prescribed wall heat flux is investigated numerically. Here, both assisting and opposing buoyancy forces are considered and studied. The non-linear coupled partial differential equ...

We present results from numerical modeling of emerging flux regions on the solar surface. The modeling was carried out by means of 3D radiative MHD simulations of the rise of buoyant magnetic flux tubes through the convection zone and into the photosphere. Due to the strong stratification of the convection zone, the rise results in a lateral expansion of the tube into a magnetic sheet, which ac...

Spherical (nonrotating) accretion flows with small-scale magnetic fields have been investigated using three-dimensional, time-dependent MHD simulations. These simulations have been designed to model high-resolution (quasi) steady accretion flows in a wedge computational domain that represents a small fraction of the full spherical domain. Subsonic and supersonic (super-fast-magnetosonic) accret...

In this work, a stabilized formulation to solve the inductionless magnetohydrodynamic (MHD) problem using the finite element (FE) method is presented. The MHD problem couples the Navier-Stokes and a Darcy-type problem for the electric potential via Lorentz’s force in the momentum equation of the Navier-Stokes equations and the currents generated by the moving fluid in Ohm’s law. The key feature...

Interstellar scintillation and angular radio wave broadening measurements show that interstellar and solar wind (electron) density fluctuations exhibit a Kolmogorovlike k−5/3 power spectrum extending over many decades in wavenumber space. The ubiquity of the Kolmogorov-like interstellar medium (ISM) density spectrum led to an explanation based on coupling incompressible magnetohydrodynamic (MHD...