Near-surface simulations Near-surface simulations of the acoustic fieldof the acoustic field

Konstantin ParchevskyKonstantin Parchevsky

Stanford University, HEPLStanford University, HEPL

Brief description of the codeBrief description of the code

1.1. Equations: linearized 3D Euler equations with force or Equations: linearized 3D Euler equations with force or pressure sources.pressure sources.

2.2. Background model: convectively stabilized JCD + Background model: convectively stabilized JCD + Vernazza & Avrett chromosphere (NVernazza & Avrett chromosphere (N22 >0). >0).

3.3. Numerical scheme: Semidiscrete, strong-stability-Numerical scheme: Semidiscrete, strong-stability-preserving Runge-Kutta time advancing scheme with preserving Runge-Kutta time advancing scheme with spatial filtering.spatial filtering.

4.4. Spatial discretization: dispersion-relation-preserving high-Spatial discretization: dispersion-relation-preserving high-order scheme with stable consistent boundary conditions order scheme with stable consistent boundary conditions with summation-by-parts properties.with summation-by-parts properties.

5.5. Boundary conditions: non-reflecting boundary conditions Boundary conditions: non-reflecting boundary conditions based on perfectly matching (PML) layer .based on perfectly matching (PML) layer .

Power maps (observations)Power maps (observations)

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frequency = 4.9342 mHz

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frequency = 3.2895 mHz

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Power maps (simulations)Power maps (simulations)

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frequency = 2.8202 mHz

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frequency = 4.9897 mHz

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Future plansFuture plans

1.1. Produce artificial data for estimation of accuracy of the Produce artificial data for estimation of accuracy of the inversion procedure of helioseismic data.inversion procedure of helioseismic data.

2.2. Simulate interaction of acoustic field from multiple Simulate interaction of acoustic field from multiple sources with a sunspot (change the background sources with a sunspot (change the background model).model).

3.3. Calculate the Green’s functions for point dipole source Calculate the Green’s functions for point dipole source and sensitivity kernels for multiple sources and and sensitivity kernels for multiple sources and compare them with Aaron’s ones.compare them with Aaron’s ones.

4.4. Include magnetic field and background flows.Include magnetic field and background flows.