Particle Relaxation Time Calculator

This tool calculates the relaxation time of spherical particles considering Stokes regime. Relaxation time is the time it takes for a particle to accelerate from one velocity to another. Particles with small relaxation time rapidly respond to changes to the surrounding air velocity. Particles with high relaxation time take longer to accelerate or slow down when the surrounding air velocity changes.

Type the required values to get the relaxation time:

Air Viscosity (µf, kg/ms)

Particle Density (ρ, kg/m3)

Particle Diameter (Dp, m)

Particle Relaxation Time (s)