$A$	Pre-exponential factor, $\mathrm{mol}\cdot {\mathrm{s}}^{-1}\cdot {\mathrm{kg}}^{-1}\cdot {\mathrm{MPa}}^{-1}$
$A_{\mathrm{c}}$	Cross-section area, ${\mathrm{m}}^2$
$C_{p,k}$	Constant pressure molar heat capacity, $\mathrm{J}\cdot {\mathrm{mol}}^{-1}\cdot {\mathrm{K}}^{-1}$
$d$	Inner diameter, $\mathrm{m}$
$E$	Reaction activation energy, $\mathrm{J}\cdot {\mathrm{mol}}^{-1}$
$F_k$	Molar flow rate, $\mathrm{mol}\cdot s^{-1}$
h	Molar enthalpy, $\mathrm{J}\cdot {\mathrm{mol}}^{-1}$
$k$	Reaction rate constant
$K$	Reaction equilibrium constant
$L$	Length, $\mathrm{m}$
$\dot{m}$	Mass flow rates, $\mathrm{kg}\cdot {\mathrm{s}}^{-1}$
$n$	Amount of substance, $\mathrm{mol}$
$p$	Pressure, $\mathrm{MPa}$
$r$	Chemical reaction rate, $\mathrm{mol}\cdot {\mathrm{kg}}^{-1}\cdot {\mathrm{s}}^{-1}$
$R$	Molar gas constant, $\mathrm{J}\cdot {\mathrm{mol}}^{-1}\cdot {\mathrm{K}}^{-1}$
$T$	Temperature, $\mathrm{K}$
$U$	Heat transfer coefficient, $\mathrm{W}\cdot \mathrm{K}\cdot {\mathrm{m}}^{-2}$
$v$	Average flow rate, $\mathrm{m}\cdot {\mathrm{s}}^{-1}$
$y_k$	Mole fraction
Greek symbol
$\eta$	Effective factor
$\epsilon$	Porosity
$\mu$	Viscosity coefficient, $\mathrm{kg}\cdot {\mathrm{m}}^{-1}\cdot {\mathrm{s}}^{-1}$
$\sigma$	Local entropy generation rate, $\mathrm{J}\cdot {\mathrm{K}}^{-1}\cdot {\mathrm{m}}^{-1}\cdot {\mathrm{s}}^{-1}$
$\rho$	Density, $\mathrm{kg}\cdot {\mathrm{m}}^{-3}$
$\Delta \dot{S}$	Entropy generation rate, $\mathrm{J}\cdot {\mathrm{K}}^{-1}\cdot {\mathrm{s}}^{-1}$
Abbreviations
isen	Ideal reversible process
M	Mixer
C	Compressor
HE	Heat exchanger
CR	Reactor