Fig 1.
The schematic diagram of the model.
Fig 2.
Pressure is plotted versus duct height for ,
,
p = q = μ = κ = r = s = 1 and N = 120, where (A) the real parts and (B) the imaginary parts.
Fig 3.
Normal velocity is plotted versus duct height for ,
,
p = q = μ = κ = r = s = 1 and N = 120, where (A) the real parts and (B) the imaginary parts.
Fig 4.
Energies versus frequency with ,
, r = s = p = q = 1 for (A)
(B)
.
Fig 5.
Energies versus a with f = 230Hz, r = s = p = q = 1 for (A) (B)
.
Fig 6.
Reflected energies against frequency for rigid, soft and impedance conditions; (A) with step-discontinuities () (B) without-discontinuities (
), where
.
Fig 7.
Reflected energies against frequency for rigid, soft and impedance conditions; (A) with step-discontinuities () (B) without-discontinuities (
), where
.
Fig 8.
Reflected energies against for rigid, soft and impedance conditions; (A) with step-discontinuities (
) (B) without-discontinuities (
), where
.
Fig 9.
Reflected energies against for rigid, soft and impedance conditions; (A) with step-discontinuities (
) (B) without-discontinuities (
), where
.
Fig 10.
Transmitted powers against frequency with absorbent linings (A) with step-discontinuities () (B) without-discontinuities (
).
Fig 11.
Transmitted powers against a with absorbent linings (A) with step-discontinuities () (B) without-discontinuities (
).