Numerical Simulation of Unsteady Compressible Flow in Convergent Channel: Pressure Spectral Analysis

Figure 6

Three vibration periods of the gap width oscillations and the acoustic pressure signals 𝑝_ac computed in the gap and at the outlet on the axis of the channel.

(a) The prescribed oscillation of gap width 𝑓=100 Hz.

(b) The acoustic pressure in the gap and DFT spectrum—𝑓₀=100Hz.

(c) The acoustic pressure at the outlet and DFT spectrum—𝑓₀=100, 𝑓₁=550, 𝑓₂=1150, 𝑓₃=1950Hz.