Convert between rotational speed, angular velocity and the linear speed at a radius.
Angular velocity is radius-independent, but the linear speed it produces grows directly with radius. That is why the tip of a long blade moves far faster than one near the hub at the same rpm. Tip speed rather than rpm is what limits turbine and fan design, because it drives both stress and noise.
Angular Velocity
ω = 2π × rpm ÷ 60; tangential speed v = ω r
ω = 2π × rpm ÷ 60; tangential speed v = ω r Angular velocity is radius-independent, but the linear speed it produces grows directly with radius. That is why the tip of a long blade moves far faster than one near the hub at the same rpm.
Tip speed rather than rpm is what limits turbine and fan design, because it drives both stress and noise.
This calculator takes 2 inputs: Rotational speed, Radius. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.