## THERMAL SCIENCE

International Scientific Journal

### Thermal Science - Online First

online first only
### Determining of geometrical characteristic parameters of particle fractal aggregates from light scattering measurement signals

**ABSTRACT**

Two kind of light scattering measurement methods, i.e. the forward light scattering measurement (FLSM) method and the angular light scattering measurement (ALSM) method, are applied to reconstruct the geometrical morphology of particle fractal aggregates. An improved Attractive and Repulsive Particle Swarm Optimization (IARPSO) algorithm is applied to reconstruct the geometrical structure of fractal aggregates. It has been confirmed to show better convergence properties than the original Particle Swarm Optimization (PSO) algorithm and the Attractive and Repulsive Particle Swarm Optimization (ARPSO) algorithm. Compared with the FLSM method, the ASLM method can obtain more accurate and robust results as the distribution of the fitness function value obtained by the ALSM method is more satisfactory. Meanwhile, the retrieval accuracy can be improved by increasing the number of measurement angles or the interval between adjacent measurement angles even when the random noises are added. All the conclusions have important guiding significance for the further study of the geometry reconstruction experiment of fractal aggregates.

**KEYWORDS**

PAPER SUBMITTED: 2020-02-14

PAPER REVISED: 2020-06-29

PAPER ACCEPTED: 2020-07-02

PUBLISHED ONLINE: 2020-07-11

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