Abstract
This paper describes an advanced method for the measurement of the particle size distribution in a gas-particle flow. The method utilizes the “classification effect” which occurred during anisokinetic sampling. When the sampling velocity is different from the main flow velocity, the measured concentration deviates from the concentration in the main flow. The ratio of the measured particle concentration to the concentration in the main flow is expressed as the function of both the velocity ratio (main flow velocity/sampling velocity) and the inertial parameter. Previous papers showed that both the median diameter and the standard deviation of the particle size distribution can be derived from this sampling method. The mothod, however, is based on the assumption of a particle size distribution function, such as the lognormal distribution.
The aim of this study is to improve the measurement accuracy of the mothod. A new procedure is investigated in which three sampling probes with different diameters are used. The method can estimate complicated particle size distributions, such as bimodal distribution, without assuming the distribution function. The results agree well with those obtained using the conventional method.
