Vol.3, No 15, 2003 pp.1077-1082
UDC 531
Invited Paper
DISCRETE FOURIER TRANSFORM
IN THE PROBLEM OF THE WAVE PACKET DYNAMICS
V.A. Zharov
Moskow Institute of Physics and Technology, Russia
Gagarin Str. 16 Zhukovsky Moscow Region 140180 Russia
e-mail: zha iv@nikoil.ru
Abstract. The method of the wave packet dynamic description for
Tollmien-Schlichting waves in boundary layer flow of incompressible fluid
is suggested. The method is based on combined using of the one-mode spectral
wave components equation and the wave packet envelope equation. This approach
is available when splitting of nonlinear equations is used for linear and
nonlinear parts at each time step. The linear part can be solved with the
use of the wave packet spectral component equation and then we transform
the field from the wave number space to the physical space. In the physical
space we solve the system of ordinary differential equations with the subsequent
inverse Fourier transformation in the wave number space. As a procedure
of discrete Fourier transformation a standard FFT is used.
DISKRETNA FOURIER-OVA TRANSFORMACIJA
U PROBLEMIMA DINAMIKE SKUPA (SVEŽNJA) TALASA
Metoda dinamike talasnog paketa opisana za Tolmien –Schlichting-ove talese
u struji graničnog sloja u nestišljivom fluidu je predložena. Metoda se
bazira na kombinovanom korišćenju jednačina za jedno-modne spektralne talasne
komponente i jednačine obvojnice svežnja talasa. Taj pristup je pogodan
za razdvajanje nelinearnih jednačina i koristi se za linearne i nelinearne
delove u svakom stepenu vremena.
U proceduri je korišćena diskretna Fourier-va trasformacija u obliku
brze Fourier-ve transformacije.
