Simulation of the kinematics and gas dynamics of the centrifugal dispersion stand

The article studies the kinematics and gas dynamics of the centrifugal dispersion stand for spheroidizing hard alloy materials. When studying the process of centrifugal spraying on an experimental setup, it was found that the behavior of particles in the volume of the dispersion chamber is determined by the aerodynamics of gas flows formed in the working chamber. It is assumed that under the influence of gas flows, a spontaneous classification of the particles of the medium occurs, determined by the size of the latter. To study the trajectory of movement of particles of powder material in the working chamber and the deposition process, a gas-dynamic model of a centrifugal dispersion unit in the SolidWorks FlowSimulation application is proposed. The developed model of the centrifugal dispersion unit showed the possibility of operational analysis of the behavior of the gas flow, the trajectory of the particles of the powder material and the temperature of the obtained powder material, depending on the design and technological factors. The simulation results allow one to determine the principles of separation of a heterogeneous medium of particles into fractions, directly at the installation for the implementation of the method.

The results of the study of uneven seed dispersion by the centrifugal distribution system of a pneumatic grain seeder

There were determined the parameters and operating modes of the centrifugal dispersion system of a grain pneumatic seeder, which ensured the minimum unevenness of the seed dispersion between the seed lines.

Zentrifugen des Wissens – Zur Enzyklopädik des Barockromans

Early modern literature has high epistemological claims. In particular, the novel as the most innovative genre of the 16th and 17th centuries was expected to negotiate and transmit knowledge about the world in an extensive way. This epistemological optimism must be understood against the background of contemporary encyclopaedic models, which offered new possibilities of reaching out for universal and total knowledge. Two variants of encyclopaedic writing are most efficient for the novel: the logic of Lullism and the miscellaneous knowledge production of Polyhistorism. Both techniques were used in baroque novels of the 17th century: Polyhistorism produced a centrifugal dispersion of knowledge throughout the texts, whereas Lullism aimed at recollecting and ordering it. This interplay is evidently present in Daniel Casper von Lohenstein’s highly digressive 3,000 page novel „Arminius“ (1689/90), with its paratextual framework of prefaces, annotations, and indices. Moreover, the reception of „Arminius“ in 18th and 19th centuries is pertinent for the subsequent critique of encyclopaedic knowledge.

Preparation of SiO2/PEG Shear Thickening System by Centrifugal Dispersion

The nano-SiO2/polyethylene glycol (PEG) dispersion system was prepared by centrifugal mixing, and its rheological properties were investigated. The results showed the revolution and rotation speed during the centrifugal mixing have a significant effect on the rheological properties of SiO2/PEG system. When the revolution speed of the centrifugal mixer was fixed at a high speed of 1200rpm, the shear thickening effect of SiO2/PEG was gradually increased with the decrease of rotation speed, and the maximum viscosity (η) of 12340 mPa•s appeared at the rotation speed of 200 rpm. At the low revolution speed of 700 rpm, the increase of the rotation speed significantly enhanced the shear thickening effect. When the rotation speed was 700rpm, the maximum viscosity was up to 86130mPa s. In steady state experiments, the systems show a shear-thinning property under low shear rate. When the shear rate exceeded a critical value (γ= 24.92 s-1), the viscosity first increased, and then decreased sharply. In the dynamic experiments, with the increase of angular frequency (ω), the loss modulus (G″) also increased and the systems behaved as a shear-thickening fluid.