Effect of Piston Size on Resonant Gas Oscillations in a Closed Tube with a Sudden Change in Cross-sectional Area

Numerical modeling was performed to study the effect of piston size on resonant gas oscillations in a closed tube with a sudden change in cross-sectional area. The results show that an increase in the piston radius, R₀ , leads to a decrease in the resonance frequency due to the increase in the tube volume. It also causes an increase in the amplitude of gas pressure oscillations at the closed end across the entire range of R₀ values studied. The maximum amplitude of gas pressure oscillations on the piston surface occurs at a ratio of m=R₀/r₀≈ 3.3 . A further increase in the piston radius ( m 3.3 ) leads to a decrease in this amplitude. The findings of this study can be used to optimize the geometry of cylindrical resonators with a sudden change in cross-sectional area.