The collection efficiency of a single filter-fiber is defined as the fraction of particles collected to the total number of particles that would have passed through the fiber if they had moved on straight lines. The total collection efficiency Ec can be defined as the sum of the collection efficiencies due to diffusion (Ed) and inertial impaction (Ei) [11]:
equation(1)
Ec=Ed+Ei=a1(dfu)−2/3+a2u/df,