# Table 1 Parameters of the gas face seal

Parameters Values
Outer radius $$r_{{\text{o}}} \left( {{\text{mm}}} \right)$$ $$61.6$$
Inner radius $$r_{{\text{i}}} \left( {{\text{mm}}} \right)$$ $$51.6$$
Spiral groove inner radius $$r_{{{\text{spr}}}} \left( {{\text{mm}}} \right)$$ $$55.5$$
Spiral groove angle $$\beta_{{{\text{spr}}}} \left(^\circ \right)$$ 15
Groove depth $$h_{{{\text{spr}}}} \left( {{\upmu \text{m}}} \right)$$ 6
Groove count $$N_{{{\text{spr}}}}$$ 12
Stator mass $$m\left( {{\text{kg}}} \right)$$ 0.2
Stator moment of inertia $$J\left( {{\text{kg}}\cdot{\text{m}}^{2} } \right)$$ $$3.5 \times 10^{ - 4}$$
Support axial stiffness $$k_{{z{\text{s}}0}} \left( {{\text{N}}/{\text{m}}} \right)$$* $$1.64 \times 10^{4}$$
Support angular stiffness $$k_{{\gamma {\text{s}}0}} \left( {{\text{N}}\cdot{\text{m}}/{\text{rad}}} \right)$$* $$31$$
Support axial damping $$c_{{z{\text{s}}0}} \left( {{\text{N}}\cdot{\text{s}}/{\text{m}}} \right)$$* $$1 \times 10^{3}$$
Support angular damping $$c_{{\gamma {\text{s}}0}} \left( {{\text{N}}\cdot{\text{m}}\cdot{\text{s}}/{\text{rad}}} \right)$$* $$1.4$$
Standard deviation of surface height $$\sigma_{{\text{a}}} \left( {{\upmu \text{m}}} \right)$$ 0.177
Standard deviation of asperity height $$\sigma_{{\text{s}}} \left( {{\upmu \text{m}}} \right)$$ 0.170
Mean of asperity height $$\overline{w}_{{\text{s}}} \left( {{\upmu \text{m}}} \right)$$ 0.114
Asperity density $$\eta_{{\text{s}}} \left( {{\upmu \text{m}}^{ - 2} } \right)$$ 0.133
Average radius of asperity tips $$R_{{\text{s}}} \left( {{\upmu \text{m}}} \right)$$ 3.02
Youngâ€™s Modulus $$E\left( {{\text{GPa}}} \right)$$ 151
Maximum contact pressure $$p_{m} { }\left( {{\text{MPa}}} \right)$$ 242.24
Gas dynamic viscosity $$\mu \left( {{\text{Pa}}\cdot{\text{s}}} \right)$$ $$1.8 \times 10^{ - 5}$$
Gas density under $$0.1{\text{MPaA}}$$$$\rho \left( {{\text{kg}}/{\text{m}}^{3} } \right)$$ 1.2
Absolute gas pressure at inner radius $$p_{{\text{i}}} \left( {{\text{MPa}}} \right)$$ $$0.1$$
Absolute gas pressure at outer radius $$p_{{\text{o}}} \left( {{\text{MPa}}} \right)$$ $$0.5$$
Land clearance at zero displacement $$h_{0} \left( {{\upmu \text{m}}} \right)$$ $$1.93$$
Rotation speed $$n_{\omega } \left( {{\text{r}}/{\text{min}}} \right)$$ $$1200$$
1. *The marked properties are scaled as a type of abnormity in the cases simulated.