ABSTRACT
Sampling efficiency was calculated using the point sink approximation. In the particle sampling processes, a so-called sampling loss occurs at the entrance and inner wall of the sampling probe so that the measured value may be incorrect. The solid lines represent upward sampling and the dashed lines show downward sampling. The inner static pressure must be equal to the outer static pressure for isokinetic sampling in the case of static-pressure-balance-type sampling probe. The sampling efficiency during anisokinetic sampling is dependent on the particle size when the main flow velocity and the diameter of the sampling probe are fixed. The sampling efficiency of mono-disperse particles has a linear relation with the velocity ratio according to C. N. Davies’ equation, so that the anisokinetic sampling efficiency can be easily estimated. In order to measure complicated particle size distributions, a new method was proposed by H. Tsuji et al. in which plural sampling probes of different diameters were employed.
