fxSolver is a solver for engineering and scientific equations.

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1. Knudsen number ( related to mean free path)

K_n	The Knudsen number (dimensionless)
λ	The molecular mean free path length (m)
L	The representative physical length scale (m)

K_nλL

2. Knudsen number (For a Boltzmann gas)

K_n	Knudsen number (dimensionless)
k_B	Boltzmann constant
T	The thermodynamic temperature (K)
π	pi
d	The particle hard shell diameter (m)
P	The total pressure, (Pa)
L	The representative physical length scale (m)

3. Knudsen number (Relationship to Mach and Reynolds numbers in gases)

K_n	Knudsen number (dimensionless)
M_a	Mach number (dimensionless)
R_e	Reynolds number (dimensionless)
γ	The ratio of specific heats (dimensionless)
π	pi

K_nM_aR_eγ

4. Knudsen diffusivity for diffusing species

D_KA	The Knudsen diffusivity for diffusing species A (m²/s)
d_pore	The pore diameter (m)
R_g	molar gas constant
T	The absolute temperature (K)
π	pi
M_A	The species molecular weigh (kg/mol)

D_KAd_poreTM_A

fx​Solver is a solver for engineering and scientific equations.