Civil Engineering Reference
In-Depth Information
This method of determining
K
holds for all cylindrical tubes. The bulk modulus
K
,
for cylindrical tubes having a circular cross-section, and slits, is represented in Figures 4.6
and 4.7 as a function of
s
and
s
, respectively. It is seen that its real part is equal to
P
0
at low frequencies (isothermal limit) and to
γP
0
at high frequencies (adiabatic limit).
These limits are detailed in Sections 4.5 and 4.6.
1.4
1.3
1.2
1.1
1
0
2
4
6
8
10
12
14
16
s
0.2
0.15
0.1
0.05
0
0
2
4
6
8
10
12
14
16
s
Figure 4.6
The bulk modulus
K
of air in a cylindrical tube having a circular cross-
section, as a function of
s
. The unit is the atmospheric pressure
P
0
.
1.4
1.3
1.2
1.1
1
02468 0 2 4 6
s
′
0.2
0.15
0.1
0.05
0
0 2 4 6 8 0 2 4 6
s
′
Figure 4.7
The bulk modulus
K
of air in a slit as a function of
s
. The unit is the
atmospheric pressure
P
0
.
