Fig. 19

Effect of polymeric foam thickness on acoustic pressure inside the inner cavity under resonance conditions at 450 Hz, 1000 Hz, and 4000 Hz. Thin polymeric foam: \({h}_{4}\) = 1 cm. Thick polymeric foam: \({h}_{4}\) = 3 cm.

Effect of polymeric foam thickness on acoustic pressure inside the inner cavity under resonance conditions at 450 Hz, 1000 Hz, and 4000 Hz. Thin polymeric foam: \({h}_{4}\) = 1 cm. Thick polymeric foam: \({h}_{4}\) = 3 cm.