# RESONANT AMPLIFICATION OF TURBULENCE BY THE BLAST WAVES

## Abstract

We discuss the idea of whether spherical blast waves can amplify by a nonlocal resonant hydrodynamic mechanism inhomogeneities formed by turbulence or phase segregation in the interstellar medium. We consider the problem of a blast-wave-turbulence interaction in the Linear Interaction Approximation. Mathematically, this is an eigenvalue problem for finding the structure and amplitude of eigenfunctions describing the response of the shock-wave flow to forced oscillations by external perturbations in the ambient interstellar medium. Linear analysis shows that the blast wave can amplify density and vorticity perturbations for a wide range of length scales with amplification coefficients of up to 20, with increasing amplification the larger the length. There also exist resonant harmonics for which the gain becomes formally infinite in the linear approximation. Their orbital wavenumbers are within the range of macro- (l ∼ 1), meso- (l ∼ 20), and microscopic (l > 200) scales. Since the resonance width is narrow (typically, Δl < 1), resonance should select and amplify discrete isolated harmonics. We speculate on a possible explanation of an observed regular filamentary structure of regularly shaped round supernova remnants such as SNR 1572, 1006, or 0509-67.5. Resonant mesoscales found (l ≈ 18) are surprisingly close to the observedmore »

- Authors:

- Physicotechnical Institute, Volgograd State University, Volgograd 400062 (Russian Federation)

- Publication Date:

- OSTI Identifier:
- 22364245

- Resource Type:
- Journal Article

- Resource Relation:
- Journal Name: Astrophysical Journal; Journal Volume: 800; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; APPROXIMATIONS; DENSITY; DISTURBANCES; EIGENFUNCTIONS; EIGENVALUES; GAIN; HARMONICS; HYDRODYNAMICS; INTERSTELLAR SPACE; RESONANCE; SHOCK WAVES; SPHERICAL CONFIGURATION; SUPERNOVA REMNANTS; TURBULENCE

### Citation Formats

```
Zankovich, A. M., and Kovalenko, I. G., E-mail: ilya.g.kovalenko@gmail.com.
```*RESONANT AMPLIFICATION OF TURBULENCE BY THE BLAST WAVES*. United States: N. p., 2015.
Web. doi:10.1088/0004-637X/800/1/28.

```
Zankovich, A. M., & Kovalenko, I. G., E-mail: ilya.g.kovalenko@gmail.com.
```*RESONANT AMPLIFICATION OF TURBULENCE BY THE BLAST WAVES*. United States. doi:10.1088/0004-637X/800/1/28.

```
Zankovich, A. M., and Kovalenko, I. G., E-mail: ilya.g.kovalenko@gmail.com. Tue .
"RESONANT AMPLIFICATION OF TURBULENCE BY THE BLAST WAVES". United States.
doi:10.1088/0004-637X/800/1/28.
```

```
@article{osti_22364245,
```

title = {RESONANT AMPLIFICATION OF TURBULENCE BY THE BLAST WAVES},

author = {Zankovich, A. M. and Kovalenko, I. G., E-mail: ilya.g.kovalenko@gmail.com},

abstractNote = {We discuss the idea of whether spherical blast waves can amplify by a nonlocal resonant hydrodynamic mechanism inhomogeneities formed by turbulence or phase segregation in the interstellar medium. We consider the problem of a blast-wave-turbulence interaction in the Linear Interaction Approximation. Mathematically, this is an eigenvalue problem for finding the structure and amplitude of eigenfunctions describing the response of the shock-wave flow to forced oscillations by external perturbations in the ambient interstellar medium. Linear analysis shows that the blast wave can amplify density and vorticity perturbations for a wide range of length scales with amplification coefficients of up to 20, with increasing amplification the larger the length. There also exist resonant harmonics for which the gain becomes formally infinite in the linear approximation. Their orbital wavenumbers are within the range of macro- (l ∼ 1), meso- (l ∼ 20), and microscopic (l > 200) scales. Since the resonance width is narrow (typically, Δl < 1), resonance should select and amplify discrete isolated harmonics. We speculate on a possible explanation of an observed regular filamentary structure of regularly shaped round supernova remnants such as SNR 1572, 1006, or 0509-67.5. Resonant mesoscales found (l ≈ 18) are surprisingly close to the observed scales (l ≈ 15) of ripples in the shell's surface of SNR 0509-67.5.},

doi = {10.1088/0004-637X/800/1/28},

journal = {Astrophysical Journal},

number = 1,

volume = 800,

place = {United States},

year = {Tue Feb 10 00:00:00 EST 2015},

month = {Tue Feb 10 00:00:00 EST 2015}

}