РЕВЕРСИРОВАНИЕ КУРСА ТРАКТОРНОГО АГРЕГАТА НА ГЛАДКОЙ ПАХОТЕ

The paper proposes a supportive maneuvering device for course reversal of a wheeled tractor unit on a smooth flat ploughing, its novelty is proved by a patent for an invention. Application of the supportive maneuvering device does not require any changes in design of commercial tractors. Theoretical and experimental investigations have been carried out in order to determine moments of resistance to course reversal according to minimum radius and time for such manouevre.Для реверсирования курса колесного тракторного агрегата на гладкой пахоте предложено опорно-маневровое устройство, новизна которого подтверждена патентом на изобретение. Применение опорно-маневрового устройства не требует изменения конструкции серийных тракторов. Проведены теоретические и экспериментальные исследования для определения моментов сопротивления реверсированию курса по минимальному радиусу и время на его осуществление

МКЭ-анализ эффективности бионической исторической консоли в качестве колонны крупногабаритного станка

Concept of machine tool’s column in the appearance of vertical bionic console is proposed. Console was 3D-transformed from the shape of legacy oak-like structure – Eddystone lighthouse. It is proposed to create the variable-section column with “layer-by-layer” technics from the polymer concrete.FEA shows high stiffness of the column. It increases from 1500 to 11000 N/μm from top to bottom along vertical guideways. Such stiffness needs only 19.3 ton of concrete for the instance of 4.5 m height’s column. FEMmodelling pointed out rather high eigenmode’s frequencies (˃49 Hz). FRF is appropriate for pre-resonance heavy cutting as for post-resonance finishing. Proposed bionic-shape column is perspective as for stand-alone variant so for portal composition created by two opposite columns.Предложена концепция станочной колонны в виде вертикальной бионической консоли. Консоль получена виртуальной 3D-трансформацией древоподобной башни исторического маяка Эдистон. Колонну предложено создавать из полимербетона с послойным формированием переменного сечения.МКЭ-анализ показал высокую жесткость колонны (от ~1500 до ~11000 Н/мкм сверху вниз). Такая жесткость достигнута для высоты колонны в 4,5 м при массе бетона только 19,3 т. МКЭ-моделирование указывает, что резонансы колонны располагаются высоко (˃49 Гц). АЧХ благоприятна для силового резания на дорезонансых частотах и для чистовой зарезонансной обработки. Возможно использование как уединенной бионической колонны, так и создание из двух оппозитно размещенных колонн портала с динамической траверсой

A state selection algorithm for the automated state model generator

A powerful technique for the modeling and analysis of lumped-parameter power-electronic-based systems with changing topology has been previously developed. In this modeling approach, the state space representation of the overall system is generated automatically and updated dynamically based upon the topological state of the system. Although this method has been applied successfully to numerous power converter circuits, it fails to produce a state model for circuit topologies that include capacitive loops. In this thesis, a generalized state model generation algorithm is set forth that is applicable for all practically useful topologies of power electronic systems. In this method, a composite electrical network is viewed as inductive, capacitive, and algebraic subnetworks interconnected with each other. Decomposition of the global system into three elementary networks enables the identification of minimal sets of natural state variables; currents (fluxes) and voltages (charges), for the inductive and capacitive subsystems, respectively. A deterministic and robust state selection algorithm based on the theory of weighted graphs has been developed to enable network partitioning. The algorithm can also be used to ensure continuity of the state variables across topological boundaries. The network identification procedure for partitioning the global system has also been extended to a more general case of multiple networks. The algorithmically-generated state equations have a well-defined structure that is convenient for efficient computer implementation and modeling of networks with different types of parameters (constant, time-varying, linear, nonlinear, etc.) and switching characteristics

AN INVESTIGATION OF FLICKER REDUCTION USING AN ADAPTIVE VAR COMPENSATOR

A detailed computer model of a three-phase power network which includes inductive loads, resistance welders and an Adaptive Var Compensator (AVC) has been developed. The system configuration and parameters correspond to an irrdustrial customer served by a large electric utility. Welder operation produces severe cyclic flicker which leads to customer complaints. Computer studies have been conducted to determine the effectiveness of the AVC on the reduction of observable flicker at neighboring loads. Flicker severity was determined using the UE 1 E C flickermeter technique adopted for 120-V incandescent lamps. Different control strategies involving the AVC have been considered and compared with respect to flicker reduction. An innovative: Flicker Adaptive Control (FAC) strategy is proposed for the AVC. The control algorithm requires knowledge of the system line impedance; however, it can be used for both power factor correction and flicker reduction, which is an advantage over previous control methods. The measurement technique used in the FAC is accurate even in presence of heavy system distortion

COURSE REVERSAL OF TRACTOR UNIT ON FLAT PLOUGHING

The paper proposes a supportive maneuvering device for course reversal of a wheeled tractor unit on a smooth flat ploughing, its novelty is proved by a patent for an invention. Application of the supportive maneuvering device does not require any changes in design of commercial tractors. Theoretical and experimental investigations have been carried out in order to determine moments of resistance to course reversal according to minimum radius and time for such manouevre

AUTOMATION OF OPERATIONAL CONTROL OF DATA FLOWS OF THE METALLURGICAL ENTERPRISE ORGANIZATIONAL STRUCTURE

New method for creation of models of operative control of enterprise is offered. The computer variant of the organizational structure, based on analysis of the charging dynamics of control units, is offered and illustrated at the example of one of organizational structures of Belorussian metallurgical works

SOFTWARE «PRONEUROLIT» FOR PROTOTYPING OF FOUNDRY TECHNOLOGIES

The neuronet algorithm and software «ProNeuroLit» are developed for choice of prototypes of gating systems on the basis of database of analogues. The different regimes of operation of «proneurolit» by choice of gating systems are shown

MODEL OF HYDRODYNAMIC MIXING OF CARBONIC POWDERS IN VACUUMATOR, USED IN STEEL-MAKING OF RUP “BMZ”

The mathematical model of the mixing and dissolving process of carbonic powder in a system '"vacuumator-bowl” under influence of circulating argon is offered. The spatial distribution of hydrodynamic currents at mixing of carbonic powder, received on the basis of computer calculations is presented. The character of distribution of hydrodynamic speeds of melt (circulating currents) in industrial bowl and vacuumator for different time slots of mixing is determined

Modeling of influence of cooled and uncooled rolls on temperatures and stresses of the industrial ingot surface in the area of the secondary cooling

On the basis of the system “ProNRS-2'' there are carried out the computer calculations of tensile and compressive stresses along the length of the ingot of size 250x300 mm for the group of industrial steels. There is received the information about the stresses in ingots from the steel 40X, 70K, 2C45, 20C45, 20XH3A. There is shown, that the highest level of tensile stresses is observed for the ingot from the steel 40X, and the lowest — for the ingot from the steel 70K

Modeling on the basis of the computer system “ProNRS-2” of the mechanical and thermal stresses in the steel ingot, moving along the radial bending at MNLZ

There are carried out the computer calculations of the stresses, arising because of the mechanical and thermal gradients in industrial ingots, with the help of the system ‘TroNRS-2”. For the ingot of size 250x300, produced at BMZ, there are presented dependences of compression and tensile stresses along the whole length of ingot. On the basis of the carried out computer calculations of the three-dimensional ingot there is shown, that in the areas of secondary cooling the thermal stresses dominate over mechanical ones, and in the area of rectification there is observed the converse tendency