Low Reynolds number drag and particle collision efficiency of a cylindrical fiber within a parallel array
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Author:
T. Müller, J. Meyer, G. Kasper
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Source:
Journal of Aerosol Science, 2014, 77, 50-66
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Accurate numerical methods were used for a systematic study of the drag coefficient and the particle collision efficiency of cylindrical filter fibers over a wide range of non-zero Reynolds numbers Re and inter-fiber distances s/dF of practical importance to gas filtration applications.
On the basis of the numerical flow field data, a novel fit function was derived for the fiber drag coefficient cD as a function of s/dF and Re for the parameter range 2 ≤ s/dF ≤ 20 and Re ≤ 20.
In the second part of the paper CFD and Miyagi-type flow fields were used to calculate the collision efficiency of spherical, non-diffusive particles for Stokes numbers of 0 ≤ St ≤ 103 and interception parameters of 0.005 ≤ R ≤ 0.5. From these numerical data, novel fit functions were derived for the collision efficiency by interception only, and for the combined efficiency by inertia and interception. The effects of fiber spacing s/dF and Re on particle inertia are accounted for by a modified Stokes number.