Random packing has important significance in both mathematical field and practical application. For a randomly close packing of ellipsoidal particle system
three important parameters
namely stacking fraction
orientational order and coordination number distribution
are accurately measured by an experimental method based on high resolution industrial CT nondestructive testing. The experimental results show that: When the aspect ratio of ellipsoid is 0.5 or 2.0
packing fraction reaches the maximum; The maximum packing fraction is 0.745 ±0.037; Within the scope of the aspect ratio of the test sample
the distribution of coordination number obeys skewed distribution; The orientation angle has high symmetry on the orientation axis. These results are quite different from those of the sphere randomly close packing. An ellipsoid packing theory is proposed under two assumptions to explain the variation trend of the packing parameters. The theoretical simulation results coincide with the experimental ones. The conclusion and the experimental means are of some reference value for researching theory of non-sphere filling and calculation of bulk porosity.
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references
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