Date post: | 20-Dec-2015 |
Category: |
Documents |
View: | 214 times |
Download: | 0 times |
Objectives
• Understand supergranulation & the magnetic network
• Find signatures of emerging magnetic flux
• Validate and refine local helioseismic methods
Competed Simulations
• Hydrodynamic solar surface convection 96 Mm wide x 20 Mm deepDuration: 20.9 hours (bootstrapped from 48 Mm wide)Resolution: 100 km horizontal, 12-75 km vertical
• 48 Mm wide x 20 Mm deepDuration: 60 hours (boostrapped from 24 Mm wide)Resolution: 100 km horizontal, 12-75 km vertical
Numerical Method• Spatial differencing
– 6th-order f.d.– staggered
• Time advancement– 3rd order Runga-Kutta
• Equation of state– tabular – including ionization– H, He + abundant elements
• Radiative transfer– 3D, LTE– 4 bin opacity distrib. fxn
• Quenching
Computational Domain
20 M
m
Computational Domain for the CFD Simulations of Solar Convection
96 Mm
96 Mm
Vertical velocity: scan from
temperature minimum to 20 Mm
depth
size of cellular
structures increases with depth
QuickTime™ and aPhoto - JPEG decompressor
are needed to see this picture.
QuickTime™ and aPhoto - JPEG decompressor
are needed to see this picture.
Streamlines: red down, blue up;15 hours; 48 x 20 Mm, vertical scale is depth
some downflows are halted, others merge into larger structures
QuickTime™ and aYUV420 codec decompressor
are needed to see this picture.
QuickTime™ and aYUV420 codec decompressor
are needed to see this picture.
Tracer particles: 48 x 20 Mm, 15 hours, vertical scale is grid not depth
(white is fastest, dark is slowest)
QuickTime™ and aYUV420 codec decompressor
are needed to see this picture.
QuickTime™ and aYUV420 codec decompressor
are needed to see this picture.
Upflows at surface come from small area at bottom (left)Downflows at surface converge to supergranule boundaries (right)
Upflows at surface come from small area at bottom (left)Downflows at surface converge to supergranule boundaries (right)
QuickTime™ and aYUV420 codec decompressor
are needed to see this picture.
QuickTime™ and aYUV420 codec decompressor
are needed to see this picture.
Streamlinesseeded
at bottom
QuickTime™ and aYUV420 codec decompressor
are needed to see this picture.
Streamlines:red=downblue=
up.Seededin the
middle
Mass Conservation
Rising fluidmust turn over and descend
within about ascale height toconserve mass.
The actualmixing
(entrainment) length in the simulation is
1.8 HP.
Vorticity:
11.75 hours, Finite Time Lyapunov Exponent
Field, subdomain 21 Mm wide
x 19 Mm high x 0.5 Mm thick,
(from 48x 20 Mm simulation)
QuickTime™ and aYUV420 codec decompressor
are needed to see this picture.
QuickTime™ and aYUV420 codec decompressor
are needed to see this picture.
Wave generation & propagation
Courtesy Junwei Zhao
QuickTime™ and aGIF decompressor
are needed to see this picture.
QuickTime™ and aGIF decompressor
are needed to see this picture.
6x6x3 Mmstreamlines seeded near bottom
QuickTime™ and aYUV420 codec decompressor
are needed to see this picture.
QuickTime™ and aYUV420 codec decompressor
are needed to see this picture.
6x6x3 Mmfieldines seeded near bottom
QuickTime™ and aYUV420 codec decompressor
are needed to see this picture.
QuickTime™ and aYUV420 codec decompressor
are needed to see this picture.