Sound Speed in a Random Flow and Turbulent Shifts of the Solar Eigenfrequencies
نویسنده
چکیده
Perturbation theory is used to calculate the frequency shift of acoustic modes of an homogeneous turbulent fluid and the frequency shifts of solar modes due to turbulent convection. For sound waves in a random flow, the fractional frequency shift is +(11/30)M in the long-wavelength limit, and the shift at short wavelengths is −(2/3)M2, where M is the average Mach number of the flow. In our model of the solar convection, the low-degree f-mode shift is positive and unobservably small, whereas the fractional frequency shift at high degrees (l ≫ 500) is −M2, where M is the Mach number of convection near the solar surface. Subject headings: turbulence − Sun:oscillations
منابع مشابه
Numerical analysis of thermal-hydraulic properties of turbulent aerosol-carbon black nanofluid flow in corrugated solar collectors with double application
In this study the effects of corrugated absorber plate and using aerosol-carbon black nanofluid on heat transfer and turbulent flow in solar collectors with double application and air heating collectors, were numerically investigated. The two-dimensional continuity, momentum and energy equation were solved by finite volume and SIMPLE algorithm. In the present investigation all the simulations w...
متن کاملWaves in structured media: non-radial solar p modes
For non-radial solar p modes we calculate corrections to the eigenfrequencies arising from the sound speed and velocity inhomogeneity of the convection zone. We use a simple periodic model, and obtain the frequency corrections by solving a Hill determinant. The frequency shifts are significant, and in most cases negative; they increase in magnitude with increasing frequency and harmonic degree ...
متن کاملUse of Stochastic Turbulence Models in Jet Acoustics
There are many approaches to determine the sound propagated from turbulent flows. In hybrid methods, the turbulent noise source field is computed or modeled separately from the far-field calculations. To have an initial and quick estimation of the sound propagation, less computationally intensive methods can be developed using stochastic models of the turbulent fluctuations. In this paper, ...
متن کاملProbing Solar Convection
In the solar convection zone acoustic waves are scattered by turbulent sound speed fluctuations. In this paper the scattering of waves by convective cells is treated using Rytov’s technique. Particular care is taken to include diffraction effects which are important especially for high-degree modes that are confined to the surface layers of the Sun. The scattering leads to damping of the waves ...
متن کاملLaminar and Turbulent Aero Heating Predictions over Blunt Body in Hypersonic Flow
In the present work, an engineering method is developed to predict laminar and turbulent heating-rate solutions for blunt reentry spacecraft at hypersonic conditions. The calculation of aerodynamic heating around blunt bodies requires alternative solution of inviscid flow field around the hypersonic bodies. In this paper, the procedure is of an inverse nature, that is, a shock wave is assumed a...
متن کامل