Viscous annular damper, impact (shock) response

Stopping stroke, peak piston force and peak hydrostatic pressure of an annular viscous damper (outer radius R₀, inner radius R₁, gap h₀) when a mass enters at a given impact velocity, including a relative-eccentricity correction.

✓ validated against legacyoriginal: /calculators/response_3.htm

Outer radius, R₀10⁻³ mInner (bore/rod) radius, R₁10⁻³ mRadial gap size, h₀10⁻³ mFluid viscosity, ηPa·sMass, mkgImpact velocity, V₀m/sRelative eccentricity, ε (0 = concentric, 1 = contact)

Damping (stopping) length, x4.86 10⁻³ m

Piston force, F_max1.59 10³ N

Hydrostatic pressure, p_max1.68 10⁶ Pa

Method & references

Impact response of an annular viscous damper: stroke, peak force and peak pressure for a mass entering at a given velocity, with an eccentricity correction to the damping coefficient.

The computation is a literal port of the original client-side JavaScript from /calculators/response_3.htm. Results are verified equal to the original by an automated golden-master test. No formula has been re-derived or “improved”.

Viscous annular damper, impact (shock) response — Engineering ABC