LABORATORY TESTS OF A FOUR-SECTION SEED WHEEL WITH GROOVES IN THE SHAPE OF A PART OF THE ROTATION SURFACE OF A TORUS

В статье рассматривается вопрос повышения качественного показателя посева семян зерновых культур, такого как неустойчивость общего высева и результаты лабораторных исследований экспериментального высевающего аппарата, катушка которого выполнена четырехсекционной, с желобками в форме части поверхности вращения тора. При помощи использования лабораторной установки проведены лабораторные исследования экспериментального высевающего аппарата для нахождения рациональных значений его конструктивных и режимных параметров, необходимых для качественной работы. Получены графические зависимости неустойчивости общего высева от частоты вращения катушки, выполненной четырехсекционной, радиуса образующей части поверхности вращения тора и длины желобка одной секции четырехсекционной катушки. В работе представлены двухмерные сечения графической зависимости, характеризующие неустойчивость общего высева от его конструктивных и режимных параметров экспериментального высевающего аппарата, катушка которого выполнена четырехсекционной, с желобками в форме части поверхности вращения тора, частота вращения катушки, выполненной четырехсекционной, радиус образующей части поверхности вращения тора и длина желобка одной секции четырехсекционной катушки, которые обеспечивают наименьшую неустойчивость общего высева [1, 2]. The article deals with the issue of improving the quality indicator of sowing cereal seeds, such as instability of total sowing and the results of laboratory research of experimental sowing machine, the reel of which is made four-sectional, with grooves in the form of a part of the torus surface rotation. Laboratory researches of experimental sowing machine to find rational values of its design and operating parameters necessary for quality work were carried out using a laboratory set-up. The graphical dependences of instability of total seeding on frequency of rotation of the four-sectional coil, the radius of the forming part of the torus rotation surface and the groove length of one section of the four-sectional wheel were obtained. The paper presents two-dimensional cross-sections of the graphic dependence that characterize the instability of total seeding on its design and operating parameters of the experimental seeding unit, the wheel of which is made four-sectional, with grooves in the form of a part of the torus rotation surface, the rotation frequency of the four-sectional wheel, the radius of the forming part of the torus rotation surface and the groove length of one section of the four-sectional wheel, which provide the lowest instability of the total seeding [1, 2].

Plane Tangent to Quasi-Rotation Surface

The analysis of a surface generated by quasi-rotation of a straight line around a circle is provided in the present paper. The considered case features a straight generatrix belonging to the plane of a circular axis of quasi-rotation and intersecting it in two points. A geometric method of determination of a point belonging to a surface given its projection on the axis plane is demonstrated. Geometric construction of the curves of intersection between the considered surface and a conic surface is presented. A method of determination of points belonging to the considered surface as points belonging to the curve of intersection of two conic surfaces is acquired. Step-by-step constructions illustrating the solution of the problem of determination of a plane tangent to the considered surface in a given point are provided. The problem is solved through the methods of descriptive geometry. Every construction is performed according to an analytic algorithm, not involving approximate methods of determination of the sought points. The construction is carried out in a CAD system through the use of tools “straight line by two points” and “circle by center and point”. The presented solution to the defined problem is connected to the solution to the problem of determination of the rays reflected from the considered surface. The results of the paper expose the geometric properties of surfaces of quasi-rotation. The provided constructions can serve as the basis for the research of optical properties of the considered surfaces.

Propagation and Reflection of Plane Waves in a Rotating Magneto-Elastic Fibre-Reinforced Semi Space with Surface Stress

The present paper investigates the propagation of quasi longitudinal (qLD) and quasi transverse (qTD) waves in a magneto elastic fibre-reinforced rotating semi-infinite medium. Reflections of waves from the flat boundary with surface stress have been studied in details. The governing equations have been used to obtain the polynomial characteristic equation from which qLD and qTD wave velocities are found. It is observed that both the wave velocities depend upon the incident angle. After imposing the appropriate boundary conditions including surface stress the resultant amplitude ratios for the total displacements have been obtained. Numerically simulated results have been depicted graphically by displaying two and three dimensional graphs to highlight the influence of magnetic field, rotation, surface stress and fibre-reinforcing nature of the material medium on the propagation and reflection of plane waves.

The Relationship between the Structure and Properties of Amino Acid Ionic Liquids

Ionic liquids based on different l-amino acids (glycine, l-valine, l-leucine, l-isoleucine, l-histidine, l-methionine, l-tyrosine, l-tryptophan, l-arginine, and l-threonine) and different cations (tetrabutylammonium (TBA), tributylmethylammonium (tBMA), didecyldimethylammonium (DDA), (2-hydroxyethyl)trimethylammonium (choline) (Chol), alkyl(C12-C14) dimethylbenzylammonium (benzalkonium) (BA), dodecyltrimethylammonium (DDTMA), hexadecyltrimethylammonium (HDTMA), octadecyltrimethylammonium (ODTMA) and 1-ethyl-3-methylimidazolium (EMIM)) have been synthesized and characterized by NMR and FTIR. Viscosity, specific rotation, surface activity, thermal stability (TG), and phase transformations (DSC) have been determined and compared with available data. Furthermore, benzalkonium, didecyldimethylammonium, dodecyltrimethylammonium, hexadecyltrimethylammonium, and octadecyltrimethylammonium amino acid ionic liquids have been shown to exhibit surface activity. The dissolution of cellulose in amino acid ionic liquids (AAILs) composed of various cations was also investigated. Cellulose was only dissolved in EMIM salts of amino acids. In particular, the influence of the cation type on selected physicochemical and spectroscopic properties were discussed. The article is a mini review on amino acid ionic liquids.

Nonlinear rotating viscoelastic jets during forcespinning process

In the usual forcespinning (FS) process, a fluid jet is forced through an orifice of a rotating spinneret leading to the formation of a jet with curved centreline. In this paper, we investigate the properties of nonlinear viscoelastic jets during the FS process. We apply scaling and perturbation techniques to determine the modelling system for the viscoelastic jets, subjected to the Giesekus constitutive equations for the stress tensor. We calculate numerically the expressions for the nonlinear steady solutions for the jet quantities such as radius, speed, stretching rate, strain rate, tensile force and trajectory. We determine these quantities for different values of the parameters such as those representing the effects due to rotation, surface tension, viscosity, jet drag and viscoelasticity. We find, in particular, that the fibre jet radius decreases and the tensile force increases with the jet arc length as well as with increasing the effects of rotation and viscoelasticity. Both viscosity and surface tension indicate stabilizing effect on the viscoelastic jet. In addition, strain rate, stretching rate and the jet speed increase with the arc length, viscoelasticity and rotation rate.

Loci of Points Equally Spaced from Two Given Geometrical Figures. Part 2: Loci of Points Equally Spaced from a Point and a Conical Surface

In this paper are studied surfaces which are loci of points (LOP) equally spaced from a point and a conical surface under a variety of the point and conical surface’ mutual arrangement. Mathematical models of such surfaces are studied, and mathematical analysis of their properties is performed, as well as 3D models of considered surfaces are constructed. Possible cases of mutual arrangement for the point and the conical surface: • the point is at the conical surface’s vertex; • the point is on the conical surface; • the point is inside the conical surface: –– on the axis, –– not on the axis; • the point is outside the conical surface. The point is on the vertex of the conical surface Γ — the obtained conical surface Ω has the same vertex, whose generatrixes are perpendicular to the generatrixes of the surface Γ. The point is on the conical surface Γ — LOP equally spaced from the surface Γ and the point O separates into a straight-line l and a surface Φ of 4th order. The line l is located in the axial plane passing through the point O and is perpendicular to the generatrix of the conical surface Γ. Obtained surface Φ has a symmetry plane passing through the axis of the conical surface Γ and the point O. Many sections of the obtained surface Φ are Pascal snails. The point is inside the conical surface on the axis. Obtained surface α is a rotation surface, and the axis z is its axis of rotation. All the sections of the surface by planes perpendicular to the axis z are circles. Point is outside the conical surface. A very interesting surface Ω has been obtained, with the following properties: the surface Ω has a support plane, which is tangent to the surface Ω on a hyperbole; the surface Ω has 2 symmetry planes; there are a circle, parabola and Pascal’s snail among the surface Ω sections. In this paper have been considered analogues between surfaces of LOP equally spaced from the cylindrical surface and the point, and from the conical surface and the point.

A Fast Approach to Obtain High-Precision Measurement of the Minimum Circumscribed Cylinder Using Computer Drawing

Roundness and spindle error motion measurements are two fundamental issues in the geometrical measuring techniques. Most of the fixture with rotating cylindrical shaft, cylinder defined by the minimum circumscribed axis, can be obtained the minimum circumscribed rotation surface high-precision axis. Generally, a more accurate measurement points, can result in a more accurate cylindrical shaft, but the longer the time of the calculation time. In this paper, the drawing method can handle a large number of measurement data to avoid lengthy and complicated calculations, and can quickly obtain the minimum circumscribed cylindrical axis precise location, deviation and cylindrical radius and tolerance. This article is the use of the minimum circumscribed cylinder theoretical approach with computer drawing ways. Comparison is relatively quick and easy. The actual display of the results, which can be easily, obtained the position, skew and deviation of the spindle. This paper will be established a cylindrical outer edge quality assessment model and provided a basis for the cylindrical outer edge quality assessment. This paper for seeking the axis of cylindrical shank is based on minimum circumscribed cylindrical theory with computer drawing method and instances for verification. The computer drawing method can be determined spindle eccentric angle and the distance of deviation, to provide a reliable model for the evaluation of rotary spindle, the mode established by the paper at the same time applicable to any other rotating spindle error evaluation.