At excitation of oscillations of the spatially distributed systems with the help of a running wave, the amplitude of oscillations depends not only on temporary dependence of stimulating influence, but also from spatial distribution. It is important at excitation of acoustic oscillations of a crate under action of an external electromagnetic wave.
By virtue of equivalence of coordinates the one-dimensional model – string rigidly fixed from both parties was taken. The external influence as a running wave is enclosed to a string. The parameters of a string and external influence are taken in view of construction of experimental installation.
The accounts were produced numerically by methods of grids, Newmark and Wilson and were compared among themselves.
Was received, that the highest amplitude of oscillations arises provided that the frequency of external force is equal to own frequency of fluctuations of a string, and length of a string is less than half of length of a wave. However at equality of frequencies of acoustic and electromagnetic fluctuations of length of waves of electromagnetic fluctuations will accept the very large values (at frequency 106 Hz – length of a wave 300 m).
It was offered two actions. First represents pulse influence – high-frequency signal is included on short time with the period equal to the period of own acoustic fluctuations of a string. The amplitude of fluctuations thus grows. Also it was offered the modulated signal – result is frequency has appeared more good. At phase modulation of