MOAT FLOW SYSTEM AROUND SUNSPOTS IN SHALLOW SUBSURFACE LAYERS

Flow patterns around old sunspots and flare activity

Newmagnetic flux emerges significantly more probably in already existing solar active regions. Based on the the Debrecen Observatory photographic observations, several active regions are collected, where at least one large, X-class flare was recorded, and emergence of new activity, birth and quick motion of new umbrae was observed in the vicinity of old spots, the new activity emerged in the ce...

Modeling the Subsurface Structure of Sunspots

While sunspots are easily observed at the solar surface, determining their subsurface structure is not trivial. There are two main hypotheses for the subsurface structure of sunspots: the monolithic model and the cluster model. Local helioseismology is the only means by which we can investigate subphotospheric structure. However, as current linear inversion techniques do not yet allow helioseis...

3D Numerical Simulation of the Separated Turbulent Shallow Flow around a Single Side Obstacle

In this paper, the performance of Reynolds Averaged Navier Stokes (RANS) simulations was evaluated to predict the flow structure developed by the presence of a sidewall obstruction in a uniform open-channel shallow flow. The study of these flow structures is important because they present in several real world configurations, such as groynes in rivers, where the erosion processes, mass transpor...

Evershed Clouds as Precursors of Moving Magnetic Features around Sunspots

The relation between the Evershed flow and moving magnetic features (MMFs) is studied using highcadence, simultaneous spectropolarimetric measurements of a sunspot in visible (630.2 nm) and near-infrared (1565 nm) lines. Doppler velocities, magnetograms, and total linear polarization maps are calculated from the observed Stokes profiles. We follow the temporal evolution of two Evershed clouds t...

Investigation of flow features around shallow round cavities subject to subsonic grazing flow