Repozytorium publikacji - Politechnika Gdańska

Standing acoustic waves in one-dimensional resonator filled with vibrationally relaxing gas, are studied. Two regimes of excitation of molecular vibrational degrees of freedom are considered, equilibrium and nonequilibrium. The acoustic energy enlarges with time in the non-equilibrium regime and decreases otherwise before formation of discontinuity. After that, it decreases due to nonlinear absorption and tends to zero in equilibrium regime and to some positive quantity otherwise. This quantity may exceed the initial acoustic energy. The nonlinear transfer of acoustic energy into the energy of non-acoustic modes is followed by slow variations of temperature with time. These variations differ from zero on average, unlike acoustic ones, they are negative in the non-equilibrium regime, responsible for acoustic cooling. The high-frequency sound (as compared with the inverse time of vibrational relaxation) and relative nonlinear phenomena in a resonator are considered.

Autorzy

• prof. dr hab. Anna Perelomova link otwiera się w nowej karcie