Viscous damping, annular (bored) piston

Damping constant and normalised impulse of an annular piston (outer radius R₀ over an inner bore/rod R₁) sliding concentrically through a viscous-fluid-filled radial gap.

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Outer radius, R₀10⁻³ mInner (bore/rod) radius, R₁10⁻³ mTravel, x10⁻³ mRadial gap size, h₀10⁻³ mFluid viscosity, ηPa·s

Damping constant, C8.48 10³ Ns/m

Normalised impulse, I₀42.41 Ns

Method & references

Viscous damping of a concentric annular piston (outer radius R₀, inner bore R₁) sliding through a radial gap h₀.

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Viscous damping, annular (bored) piston — Engineering ABC