Stokes number

Stokes number

The Stokes number, named after Irish mathematician George Gabriel Stokes, is a dimensionless number corresponding to the behavior of particles suspended in a fluid flow. Stokes number is defined as the ratio of the stopping distance of a particle to a characteristic dimension of the obstacle, or


Stk = frac{ au,U_o}{d_c}

where au is the relaxation time of the particle, U_o is the fluid velocity of the flow well away from the obstacle and d_c is the characteristic dimension of the obstacle. For Stkgg 1, particles will continue in a straight line as the fluid turns around the obstacle therefore impacting on the obstacle. For Stkll1, particles will follow the fluid streamlines closely.

References

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External links

* [http://www.iop.org/EJ/article/1367-2630/6/1/119/njp4_1_119.html Reynolds number scaling of particle clustering in turbulent aerosols]


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