Theory of oscillations performed by tools in spiral potato separator
Laen...
Kuupäev
2020
Kättesaadav alates
Autorid
Bulgakov, V.
Holovach, I.
Ruzhylo, Z.
Fedosiy, I.
Ihnatiev, Ye.
Olt, Jüri
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Abstrakt
The aim of this study is to provide for the intensification of the process of removing
impurities from the potato heap by oscillating devices, which takes place, when potato tubers are
cleaned in the spiral separator during their lifting. The authors have devised a new design of the
spiral separator, which can be used in the process of lifting potatoes from the soil. It comprises
cantilever cleaning spiral springs, which in their simultaneously rotary and oscillatory motion
clean and transport the potato tubers with good quality. However, the removal of impurities from
the cleaning area and the cleaning of the side surfaces of potato tuber bodies from the stuck soil
can be significantly more effective, if the spiral springs perform their oscillatory motions in the
longitudinal and vertical plane during their operation more intensively. In order to achieve that,
the authors have worked out a new theory of the oscillatory motion of the cleaning spiral working
under the action of the potato heap. That promotes the intensification of the process of cleaning
potato bodies from the stuck soil. The authors have generated a new partial differential equation,
which describes the oscillations of the cantilever cleaning spiral. The PC-assisted numerical
solving of the said differential equation and further numerical modelling have made it possible to
obtain the analytic expressions of the relations between the change in the helix pitch distance of
the cleaning spiral and its deformation, in particular, the simultaneous longitudinal extension and
transverse bending. That result, in its turn, provided for finding the maximum limit amount of the
above-mentioned deformation under the condition that the potato tubers may not fall through the
spaces between the spiral turns, taking into account the design and kinematic parameters of the
cleaning spiral itself, the material it is made of and the process-dependent mode of operation of
the separator. As a result of the PC-assisted numerical modelling, it has been found that the total
deflection of the spiral on its length varies within the range of 0 to 0.05 m under the following
parameters: angular velocity of rotation of the spiral ω = 30 rad s-1, density of the material of the
spiral ρ = 7,700 kg m-3, elastic modulus Е = 2∙1011 Pa, cleaning spiral bar stock radius r = 8.5 mm
and a uniform load intensity of 1000 N m-1. Such variation ensures the good quality of cleaning
and transportation of potato tubers. According to the results of the PC-assisted numerical
calculations, the helix pitch distance of a cleaning spiral with the above parameters and the
original helix pitch distance S = 48 mm, due to the spiral’s deformation under the proposed
transverse oscillations, can change up to 54 mm, which makes impossible for potato tubers to fall
out of the cleaning unit. Experimental studies fully support the results from the theoretical
calculations to determine the displacement of the ends of the cleaning unit’s spiral springs.
Kirjeldus
Märksõnad
cleaning unit, deformation, oscillatory motion, potato, soil, articles