### Abstract

An initial-value problem is formulated for a threedimensional wave packet in a hypersonic boundary layer flow. The problem is solved using a Laplace transform with respect to time and Fourier transforms with respect to the streamwise and spanwise coordinates. The solution can be presented as a sum of modes consisting of continuous and discrete spectra of temporal stability theory. Two discrete modes, known as Mode S and Mode F, are of interest since they may be involved in a laminar-turbulent transition scenario. The continuous and discrete spectrum are analyzed numerically, and the following features are revealed: (1) the synchronism of Mode S with acoustic waves at low wave number is primarily twodimensional; (2) at high angles of dis turbance propagation, Mode F is no longer synchronized with entropy and vorticity waves; (3) at high angles of disturbance propagation, the synchronism between Mode S and Mode F no longer leads to a Mode S instability, and at even higher angles of disturbance propagation, Mode S and Mode F are not synchronized.

Original language | English (US) |
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Title of host publication | 34th AIAA Fluid Dynamics Conference and Exhibit |

State | Published - 2004 |

Event | 34th AIAA Fluid Dynamics Conference and Exhibit 2004 - Portland, OR, United States Duration: Jun 28 2004 → Jul 1 2004 |

### Other

Other | 34th AIAA Fluid Dynamics Conference and Exhibit 2004 |
---|---|

Country | United States |

City | Portland, OR |

Period | 6/28/04 → 7/1/04 |

### Fingerprint

### ASJC Scopus subject areas

- Engineering (miscellaneous)
- Aerospace Engineering

### Cite this

*34th AIAA Fluid Dynamics Conference and Exhibit*

**Initial-value problem for three-dimensional disturbances in a hypersonic boundary layer.** / Forgoston, Eric; Tumin, Anatoli.

Research output: Chapter in Book/Report/Conference proceeding › Conference contribution

*34th AIAA Fluid Dynamics Conference and Exhibit.*34th AIAA Fluid Dynamics Conference and Exhibit 2004, Portland, OR, United States, 6/28/04.

}

TY - GEN

T1 - Initial-value problem for three-dimensional disturbances in a hypersonic boundary layer

AU - Forgoston, Eric

AU - Tumin, Anatoli

PY - 2004

Y1 - 2004

N2 - An initial-value problem is formulated for a threedimensional wave packet in a hypersonic boundary layer flow. The problem is solved using a Laplace transform with respect to time and Fourier transforms with respect to the streamwise and spanwise coordinates. The solution can be presented as a sum of modes consisting of continuous and discrete spectra of temporal stability theory. Two discrete modes, known as Mode S and Mode F, are of interest since they may be involved in a laminar-turbulent transition scenario. The continuous and discrete spectrum are analyzed numerically, and the following features are revealed: (1) the synchronism of Mode S with acoustic waves at low wave number is primarily twodimensional; (2) at high angles of dis turbance propagation, Mode F is no longer synchronized with entropy and vorticity waves; (3) at high angles of disturbance propagation, the synchronism between Mode S and Mode F no longer leads to a Mode S instability, and at even higher angles of disturbance propagation, Mode S and Mode F are not synchronized.

AB - An initial-value problem is formulated for a threedimensional wave packet in a hypersonic boundary layer flow. The problem is solved using a Laplace transform with respect to time and Fourier transforms with respect to the streamwise and spanwise coordinates. The solution can be presented as a sum of modes consisting of continuous and discrete spectra of temporal stability theory. Two discrete modes, known as Mode S and Mode F, are of interest since they may be involved in a laminar-turbulent transition scenario. The continuous and discrete spectrum are analyzed numerically, and the following features are revealed: (1) the synchronism of Mode S with acoustic waves at low wave number is primarily twodimensional; (2) at high angles of dis turbance propagation, Mode F is no longer synchronized with entropy and vorticity waves; (3) at high angles of disturbance propagation, the synchronism between Mode S and Mode F no longer leads to a Mode S instability, and at even higher angles of disturbance propagation, Mode S and Mode F are not synchronized.

UR - http://www.scopus.com/inward/record.url?scp=84896795104&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84896795104&partnerID=8YFLogxK

M3 - Conference contribution

AN - SCOPUS:84896795104

SN - 9781624100314

BT - 34th AIAA Fluid Dynamics Conference and Exhibit

ER -