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/d(F) 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 c(D) as a function of s/d(F) and Re for the parameter range 2 <= s/d(F) <= 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 <= 10(3) 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. (C) 2014 Elsevier Ltd. All rights reserved.