Evaluation of Free-Fall Particle CT Images Using State Transition Matrix

摘要

Spatial particle density distribution images in a pipe cross section have been evaluated by means of state transition matrix, which is a parameters indicating the dominant particle density transition patterns among time series images consisting of CT 2-D space and 1-D time. State transition characterizes the transition patterns for positions in a cross section as monotonous transitions, sudden transitions, and extreme value transitions. IN a simulation, the real part of the state transition matrix is negative and the imaginary part is zero in the case of monotonous transition. The real part is positive and the imaginary part is zero in the case of extreme value transition. The imaginary part is nonzero in the case of sudden transition. In free-fall particles in a vertical pipe, high, sudden, and extreme value transitions do not occur because the particle flow rate at this position is own, and therefore the probability of collision among particles is also low. High, sudden, and extreme value transitions occur near the pipe center when the particle flow rates is high, because the probability of collision among particles is high.