Parameters	Description
${\mathrm{C}}_{\mathrm{PHB}}$	Dry weight of cell (g/L)
Kd	Cell death rate (s/1)
μ	Growth rates for cell mass (1/s)
μmax	The maximum specific growth rate of microorganisms (1/s)
S	The concentration of limited substrate for growth (g/L)
Ks	Monod constant (g/L)
α	Fixed cell death time (s−1)
Kd (∞)	Infinite cell death rate (s−1)
${\mathrm{u}}_{\mathrm{l}}$	Velocity value in (m/s)
p	Pressure in (Pa)
ϕ	Volume fraction indicated with m3/m3
$\rho$	Density value with kg/m3
g	Gravity unit with m/s2
F	N/m3
μL	Dynamic velocity Pa.s
mgl	The mass transfer rate from gas to liquid (kg/m3)
Uslip	Relative velocity
Udrift	Drift velocity
M	The molecular weight of the gas (kg/mol)
R	Ideal gas constant (J/(mol·K) 3/3141472)
T	Temperature (K)
Pref	Scalar variable at (1 at or 101.325 Pa)
μ	Effective viscosity