Trunov O. The wave propagation in the bent waveguides.

The propagation of SH-wave in bent elastic waveguide in the case of free boundaries is considered. Dimensions of the waveguide are proportional to the wave length. The problem was solved by the method of partial regions. Frequency and phase relationships of modes in bent waveguide were constructed. The comparative analysis of modes in bent waveguide and in straight waveguides was done. The infinite system of algebraic equations from matching condition was determined and using method of reduction was solved. Calculation of energy transmission coefficient through the bend and coefficients of excitation of the modes beyond the bend in the waveguide depending on geometrical parameters of the waveguide was done. Obtained result fulfillment of matching condition and law of energy conservation was checked. At certain combinations of these parameters is the dominance of one of the waveguide modes. Two representations of wave mode structure in the bend were used in current article. Calculated fields in the waveguide using both representations are equal. The propagation of the pulse signal in the bent waveguide with constant width was considered. The possibility of saving pulse signal shape was shown. The plane problem of wave propagation in the waveguide with thickened bend was considered. Calculation of energy transmission coefficient through the bend depending on the angle of the bend and size of the waveguide was done. The plane problem of wave propagation in the waveguide with two bends was considered. Two variants of bend were researched: kink and curvature. The results of these variants were compared. Calculation of energy transmission coefficient through the bends and coefficients of excitation of the modes beyond the first and the second bend in the waveguide depending on geometrical parameters of the waveguide was done. Transmission coefficient in curved waveguide almost equals unity unlike the waveguide with kink.