Spiral-groove thrust bearing (design)

Operating speed, friction torque and power loss for an axial spiral-groove thrust bearing carrying a given load, from the groove geometry and film thickness.

✓ validated against legacyoriginal: /calculators/e9_4.htm

Load, FNDiameter, DmmFilm thickness, h₀µmGroove depth + film, h₁µmDynamic viscosity, ηµPa·sGroove radius ratio, λGroove angle, α°Number of grooves, k

Speed, n4.151284179984802 rpm

Angular speed, ω0.4347214627601261 rad/s

Friction torque, T0.00009006636222044576 N·m

Friction power, P0.00003915378072995554 W

Friction coefficient, µ0.00012008848296059435

Design coefficients

Film ratio, δ = h₀/h₁0.375

H0.2727272727272727

g₁0.09109881889876449

g₂0.7369839202752009

C₂0.8982198410534472

Load coefficient, F̄0.3614995812884462

µ₁1.125829527755572

Scarce-core calculator with essentially no free equivalent. Default values are for an air-lubricated bearing (η ≈ 18.1 µPa·s).

Method & references

Narrow-groove (Muijderman) theory for spiral-groove thrust bearings.
Solves for the operating speed at which the given load is carried on the given film.

The computation is a literal port of the original client-side JavaScript from /calculators/e9_4.htm. Results are verified equal to the original by an automated golden-master test. No formula has been re-derived or “improved”.