rkz 1.2.0
Rémi Thebault <remi.thebault@gmail.com>
Computes compression factor of several gases and mixtures in conditions of
pressure and temperature using the either of the following equations of state:
- Van der Waals
- Redlich-Kwong (default)
- Soave-Redlich-Kwong
- Peng-Robinson
PV
The compression factor for a mole of gas is defined as Z = --.
RT
A range can be provided instead of scalar values for pressure or temperature. In
such case, the result is written in CSV format with one Z value per combination
of pressure and temperature (1 row per pressure condition, 1 column per
temperature condition).
Range are provided in the form of min:max[:step] (e.g. '20:800' or '20:800:10').
If step is omitted, it is assumed to be equal to one.
Mixture for option --gas|-g can be specified in the form of
molar_fraction%gas_id+[molar_fraction%gas_id]. Mixture molar fractions can only
be specified as percentage or be omitted. Gases without molar fraction evenly
take the rest of the mixture. Examples:
- '80%N2+20%O2' => 80% Nitrogen and 20% Oxygen
- '80%N2+O2' => 80% Nitrogen and 20% Oxygen
- '80%N2+O2+CO2' => 80% Nitrogen, 10% Oxygen and 10% Carbon dioxide
- '78%N2+21%O2+Ar' => air composition (more or less)
- 'N2+O2' => 50% Nitrogen and 50% Oxygen
DISCLAIMER: rkz is provided "as is" without any warranty. See the --license
option for details.
USAGE:
rkz [FLAGS] [OPTIONS]
FLAGS:
-h, --help Prints help information
--license Prints the license text and exits
--list-gas Prints a list of referenced gases
-V, --version Prints version information
OPTIONS:
-e, --eos <equation>
Specify the equation of state (case insensitive). Choices are VdW
for Van-der-Waals, RK for Redlich-Kwong, SRK for Soave-Redlich-Kwong
and PR for Peng-Robinson. [default: RK]
-g, --gas <gas>
Specify the gas by id or by mixture spec (see above)
-p, --pressure <pressure>
Specify the pressure in bar. By default absolute unless --relative
is used. A range can be specified in the form of start:stop[:step].
-r, --relative <relative>
Specify that the pressure is relative to the pressure indicated in
this parameter (in hPa). "stdatm" can be used for 1013.25.
-t, --temperature <temperature>
Specify the temperature in °C. A range can be specified in the form
of start:stop[:step].
EXAMPLES:
rkz --list-gas
Print a list of all gases referenced in RKZ
rkz -g N2 -p 200 -t 20
Z-factor of Nitrogen at 200bar and 20°C
rkz -g 78%N2+21%O2+Ar -p 200 -t 50 -e PR
Z-factor of air at 200bar and 50°C with Peng-Robinson equation of state
rkz -g H2 -p 0:1000:10 -t -40:80 -r stdatm
Z-factor CSV table of Hydrogen from 0 to 1000barG and -40 to +80°C