Driving and damping of oscillations
We have simulated the upper 2.5 Mm of the solar convection zone using a realistic, three-dimensional, compressible, hydrodynamic computer code. P-mode oscillations are excited at the eigenfrequencies of the simulation volume. We have calculated the time averages of the work terms in the kinetic energy equation, using the internal energy equation to evaluate the fluctuations in the gas pressure. This calculation shows that the modes are excited near the surface by the divergence of the convective flux and damped by the divergence of the radiative flux. The fundamental mode is also spuriously driven at the lower boundary, by density and turbulent pressure fluctuations induced when downward plunging convective plumes pass through the lower boundary of the simulation.
KeywordsFundamental Mode Solar Surface Convective Flux Boundary Work Solar Convection Zone
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