fixed throttle to the cylinder. Assuming that the gas source pressure is 35 or 70 MPa
and the temperature is 293 K, the initial pressure of the vehicle-borne hydrogen
storage cylinder is 0.16 MPa.
Vehicle-borne gas cylinders usually take a short time in the hydrogenation
process of hydrogenation station. In order to simplify the calculation, the heat
exchange between the gas inside the cylinder and the outside is neglected and
assumed to be an adiabatic process.
(1) Gas continuity equation
dM
dt
¼ Q m
ð13:16Þ
(2) Dynamic equation of cylinder pressure
From the Van der Waals equation of real gases, it is obtained that
dp
dt
¼
RT
l V
V À
b
l M
2 À
2
lV
ð Þ
2
M
2
6
4
3
7
5
dM
dt
þ
R
l M
V À
b
l M
dT
dt
ð13:17Þ
(3) Gas cylinder energy equation and temperature differential equation
According to the first law of thermodynamics and basic properties, there are
dU þ dE k þ dE p ¼ hdM þ Dq
ð13:18Þ
dU ¼ d Mu
ð Þ ¼ udM þ Mdu
ð13:19Þ
where
d Prefix, denotes increment;
U Gas internal energy;
E k Kinetic energy;
E p Potential energy;
h Specific enthalpy of gas source;
Q Quantity of heat.
Without considering the change of kinetic energy and potential energy, dQ is 0
in adiabatic process. There is
dT
dt
¼
kT A À T
M
dM
dt
ð13:20Þ
13.2 Hydrogen Transmission and Hydrogenation Characteristics …
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