A	Water permeability [L/(m2 h bar)]
ACS	Cross-section area [m2]
B	Solute permeability [L/(m2 h)]
c	Concentration [mol/L]
cosm	Osmolality [osmol/kg]
dh	Hydraulic diameter [m]
D	Diffusion coefficient of solution [m2/s]
J	Flux
JS	Reverse solute flux [g/(m2·h)]
JW	Permeate flux [L/(m2·h)]
k	Mass transfer coefficient from bulk solution to membrane interface [m/s]
L	Flow channel length [m]
lu	Wetted perimeter [m]
MSE	Mean square error
NSE	Nash-Sutcliffe efficiency [-]
R	Universal gas constant [J/(K·mol)]
Re	Reynolds number [-]
S	Structural parameter [m]
Sc	Schmidt number [-]
Sh	Sherwood number [-]
T	Temperature [K]
v	Fluid velocity [m/s]
Greeks
β	Concentration [g/L]
ρ	Density [kg/m3]
Δ	Difference
κ	Electrical conductivity [µS/cm or mS/cm]
η	Dynamic viscosity [Pa·s]
π	Osmotic pressure [bar]
ϑ	Temperature [°C]
Subscripts
DS	Draw solution
exp	Experimental value
FS	Feed solution
mod	Modelled value
N	Number of values
t	Time