dispersed gas phase and varies within the limits of P
0
changes.
The ratio of thermodynamic parameters of the dispersed gas phase with pressure
changes P
0
depends on the velocity of the processes. The changes in P
0
are close to an
isothermal process at limited speeds and adiabatic process at fast speeds. Assuming that
the form of gas bubbles is close to a sphere with some variety in absolute sizes, then the
volumes and areas of their surfaces are:
2
3
;
6
1
d
S
d
V
b
b
=
=
.
(30)
The relationship between the pressures and volumes of bubbles in isothermal and
adiabatic processes are respectively:
k
V
V
P
P
V
V
P
P
=
=
1
2
2
1
1
2
2
1
;
,
(31)
where k is the adiabatic index.
The ratio of surface areas with pressure changes from P
1
to P
2
for an isothermal
process is:
2
3
2
1
1
2
=
Р
Р
S
S
b
b
,
(32)
and for an adiabatic process it is:
2
3
2
1
1
2
=
k
b
b
Р
Р
S
S
.
(33)
The calculation results of estimating the effects of variable pressures for isothermal
processes are presented in Table 3.
Table 3 Calculated data of estimating variable pressures on the contact surface
between phases
Р
1
/Р
2
0.1 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.0
1
2
b
b
S
S
0.215 0.342 0.543 0.711 0.86 1.0 1.129 1.25 1.37 1.48 1.59 1.69 1.79 1.89 1.987 2.08
Isothermal processes should be given preference, since the implementation of
instantaneous changes in pressure P
1
to P
2
is complicated. Additionally, the effects of
hydrostatic pressures change the absolute values of S
1
to S
2
ratios, since the P
1
/P
2
ratio
by the height of gas-liquid medium is different. At the same time, the general conclusion
regarding the entire volume of the medium is this: the increase of pressure above liquid
reduces the gas retention capacity and interphase surface. Obviously, the inverse pressure
change corresponds to an increase in the specified parameters.
These properties of gas-liquid media in response to pressure variations allow us to
evaluate them as quasi-elastic, whose transformations change the gas solubility rates
according to Henry's law. It is obvious that this refers to dissolved nitrogen, oxygen, and
carbon dioxide, and the level of feedback also depends on the duration of transition
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