c	radius clearance/mm
d	molecular diameter of the gas
D	inverse Knudsen number
D 0	characteristic inverse Knudsen number
D(x,y), D(ε,θ)	Dimensionless damping coefficients
E 0	perturbation amplitude of eccentricity
H	dimensionless film thickness, H = h/c
H 0	Dimensionless steady film thickness
HE, HΘ	derivative of Hd0 to. E0 and Θ0
Kn	Knudsen number
K(x,y), K(ε,θ)	Dimensionless stiffness coefficients
L	bearing length/mm
n	Journal rotating speed/r·min−1
N	Dimensionless friction work consumption
m	molecular mass of the gas
pa	atmospheric pressure/Pa
P	dimensionless pressure, P = p/pa
P 0	Dimensionless steady film pressure
PE, PΘ	derivative of Pd0 to. E0 and Θ0
Qcon	flow rate for continuum flow
Qp	flow rate coefficients for Poiseuille flows
${\overline{Q}}_p$	dimensionless flow rate coefficients for Poiseuille flows
r	bearing radius/mm
rj	journal radius/mm
R	gas constant
Rg	gas constant/J·mol−1·K−1·kg−1
Ta	temperature/K
ε	eccentricity ratio
ε 0	eccentricity ratio in static position
θ	attitude angle/deg
θ 0	attitude angle in static position/deg
Θ 0	perturbation amplitude of attitude angle/deg
Λ	bearing number
μ	air viscosity/Pa·s
τ	dimensionless time
φ, ψ	cylinder coordinates
Ω	Perturbation frequency ratio