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arXiv · 1401.3642

Radial Stellar Pulsation and Three-Dimensional Convection. III. Comparison of Two-Dimensional and Three-Dimensional Convection Effects on Radial Pulsation

Christopher M. Geroux·Robert G. Deupree
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Abstract

We have developed a multidimensional radiation hydrodynamics code to simulate the interaction of radial stellar pulsation and convection for full amplitude pulsating models. Convection is computed using large eddy simulations. Here we perform three-dimensional simulations of RR Lyrae stars for comparison with previously reported two-dimensional simulations. We find that the time dependent behavior of the peak convective flux on pulsation phase is very similar in both the two-dimensional and three-dimensional calculations. The growth rates of the pulsation in the two-dimensional calculations are about $0.1\%$ higher than in the three-dimensional calculations.The amplitude of the light curve for a 6500 K RR Lyrae model is essentially the same for our 2D and 3D calculations, as is the rising light curve. There are differences in slope at various times during falling light.

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Christopher M. Geroux, Robert G. Deupree. 2014-01-15. Radial Stellar Pulsation and Three-Dimensional Convection. III. Comparison of Two-Dimensional and Three-Dimensional Convection Effects on Radial Pulsation. https://doi.org/10.1088/0004-637x%2F783%2F2%2F107

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