The Question of Drawing a Design Scheme of a Wagon with a Non-Symmetrically Located Freight

Violations of the stability of a wagon with an asymmetrically positioned freight can lead to a threat to the safety of train traffic, the safety of freight on the route and transport facilities. The design diagram of a wagon with an asymmetrically located freight drawn up in the article and the equations obtained in an analytical way, oscillations of the sprung mass of a wagon with an asymmetric arrangement of the freight, characterizing the longitudinal and transverse displacement of the center of mass of the freight, can be used for mathematical modeling of forced vibrations and impact on the track of a wagon with asymmetrically located freight in various operating conditions.

OPTIMIZATION OF CALCULATION SCHEMES

Any calculation is preceded by the stage of creating a design diagram of a real structure, which would most accurately correspond to real operating conditions. The more optimally the design scheme is drawn up, the less laborious the stages of calculation and design of the corresponding structure will be. There are practically no results of using this approach when calculating building structures. This article attempts to show the possibility and expediency of using the "Search for solutions" (add-on for Microsoft Excel) at the stage of choosing the optimal parameters of the design design schemeAny calculation is preceded by the stage of creating a design diagram of a real structure, which would most closely correspond to real operating conditions. The more optimally the design scheme is drawn up, the less laborious the stages of calculation and design of the corresponding structure will be. If the efficiency criterion is a linear function, and the variables in the constraint system are also linear, then such a problem is a linear programming problem. Of the listed methods of mathematical programming, the most common and developed is linear programming. To illustrate the idea of the proposed approach, a simple statically definable truss on two supports was deliberately chosen. This is done so that the idea of the proposed approach is not lost due to the complexity and cumbersomeness of the calculations. This article shows the possibility and feasibility of using the "Search for solutions" at the stage of choosing the optimal parameters of the design design scheme. After the design scheme has been defined, more powerful conventional means of calculating building structures can be involved for its complete calculation.

Modeling of the electric drive of the main motion of the rolling cage as a multi-mass electromechanical system

The model of rolling stand of a thick-plate rolling mill 3000 has been designed in the work in order to determine the oscillations frequencies that occur during operation, the effect of their amplitude on the dynamic deviations of the speed of the working body from the specified one.Presented results of the research dynamic to rolling cage 3000 at presentation her as seven masses electromechanic system. Shown influence clearance in mechanical issue on dynamic of the mechanism.The research by the method of mathematical modeling in the design and operation of mechanical equipment is substantiated.The design diagram of mechanical part of the electromechanical system is presented.Using the simulation results it was confirmed that the influence of internal viscous friction in shafting on the oscillation damping is not significant in relation to the damping properties of electric drive.Therefore, in the first approximation, it can be ignored. The electric drive of the rolling stand was considered as a TP-D system with speed and current regulators at their standard settings to the modular optimum. To reduce the magnitude of the elastic moments in the kinematic chain of the stand the armature current intensity generator in the electric drive is used.Simulation of the processes was carried out in Simulink of the MATLAB package.Thestand model is designed according to design scheme and reflects the branching into two channels with their combination through an elastic element – the material that is rolled.Based on real geometry and taking into account the properties of material the stiffness of shafts of mechanical transmissions were calculated.The model was set to a rolling program with a variable speed – in order to compensate the thickness difference, which corresponds to modern technological trends.Comparing the simulation results, it was found that the presence of a gap provokes the appearance of self-oscillations, the damping of which in a real mechanical system will occur due to damping properties of the shafts.The damping of oscillations takes place due to the damping properties of the electric drive. The appearance of a gap in the spindles leads to an increase in the system vibration frequency (70-80 Hz).

Study on mechanisms of tillage for melon cultivation under the film

The aim of the study is to develop a machine for preparing the soil for sowing melons under a tunnel film. The authors have developed a machine for preparing the soil for sowing melons under a tunnel film, which is equipped with deep-diggers with an inclined stand of the “paraplau” type, a furrow maker and rotary working bodies. A design diagram and a fragment of the machine operation have beak given. The basic principles and methods of classical mechanics, mathematical analysis and statistics were used in this study. Tests have established that the developed machine reliably performs the specified technological process and its performance indicators fully meet the requirements. When using the developed machine for preparing the soil for sowing melons under the film, the direct cost of processing one hectare of area is reduced by 33.4%. The study’s goal is to create a machine that prepares soil for seeding melons under a tunnel film. The authors have created a machine that includes deep-diggers with a “paraplau” style inclined platform, a furrow maker, and rotating working bodies for preparing the soil for planting melons beneath a tunnel film. A design schematic as well as a portion of the machine functioning has been provided. In this work, the fundamental concepts and methodologies of classical mechanics, mathematical analysis, and statistics were employed. The created machine reliably executes the required technical procedure, and its performance indicators completely fulfill the criteria, according to tests. The direct cost of processing one hectare of land is lowered by 33.4 percent when utilizing the developed machine to prepare the soil for growing melons beneath the film.

Combination machine for soil cultivation and sowing grain

The purpose of the study is to substantiate the design scheme and parameters of the working bodies of a combined machine for tillage and sowing grain on sloping lands. The authors have developed a machine that performs technological operations for tillage, grain sowing, and ridge formation to prevent water erosion. The design diagram is given. The basic principles and methods of classical mechanics, mathematical analysis, and statistics were used in this study. Theoretical and experimental studies have established that using a chisel-shaped ripper with loosening knives as a loosening working body provides high-quality loosening of the soil. When the longitudinal and transverse distances between the rippers are 62.5 and 15 cm, respectively, the longitudinal distance between the rear ripper and the housing is 60 cm, and the transverse distance between the buildings is 90 cm, high-quality soil loosening, and grain sowing are achieved with minimal energy consumption.

Variation of reaction forces on the axles of the road train depending on road longitudinal slope

The article discusses the influence of the road longitudinal slope on variation in reaction forces on the wheels of the road train. The description of the longitudinal slope of the road and methods of its determination are given. The design diagram of the forces and moments acting on the road train during its movement uphill and downhill is presented. Equations for calculating the change in the load on the three axles of the road train, depending on the longitudinal slope of the road and the mode of movement, are presented. Based on the calculation results, graphs were constructed to illustrate the change in loads on three axles of the road train. The results show that the changes in the normal reactions on the front axle of the road train are significant, affecting the braking properties and driving safety of the vehicle. The scheme for calculating the variation in loads on the axles of a road train can be used to automatically adjust the braking forces between the wheels depending on the loads and thereby ensure traffic safety.

Means of filling gas-filled cars. Lecture No 7. Part 2. Design features of mobile automobile gas filling stations with liquefied petroleum gas (AGZS)

The characteristics and parameters of mobile means of transportation and refueling of LPG are given. The characteristics of a mobile automobile gas filling station of frame and frameless construction are analyzed. The basic technological scheme of the APCT-9611 gas tanker is given. The characteristics and operating principle of the shut-off and safety equipment of the transport tank are given. A design diagram of an electric pump for supplying LPG to a mobile gas tanker is presented. A schematic diagram of a reciprocating LPG flow volume Converter is presented. The features of the mechanical and electromagnetic LPG level indicator in a transport tank are described. A schematic diagram of a mobile universal (discharge/filling) gas process module UTMG-01 is shown. Keywords: liquefied petroleum gas; mobile frame and frameless construction of a tanker truck; characteristics and parameters of the station; gas equipment, pumping unit; gas meter; principle and operating modes of the LPG level indicator. [email protected]

Impact of ship operations aided by voyage optimization on a ship’s fatigue assessment

In this study, different operation factors affecting a ship’s wave statistics are studied, such as the slow steaming and voyage optimizations. Especially, the impact of various voyage optimization methods on the long-term wave statistics and corresponding fatigue damage during ship operations is investigated by comparing the encountered waves with the design wave scatter diagram. Three years of full-scale measurements from a container ship sailing in the North Atlantic are employed to study the impact, in addition to noon reports from two fleets of container ships and VLCCs. Furthermore, the benefits of using voyage optimizations for minimum fatigue damage accumulation during operation are discussed. The large difference of wave statistics is found when the ship follows routes generated by various optimization methods and the design diagram. For some westbound voyages, the voyage optimization methods can significantly decrease the ship’s fatigue damage accumulations, leading to longer fatigue life.

EXAMPLE OF GRAGUAL TRANSFORMATION OF STIFFNESS MATRIX AND MAIN SET OF EQUATIONS AT ADDITIONAL FINITE ELEMENT METHOD

The paper considers the example of gradual transformation of the stiffness matrix and the main set of equations at Additional Finite Element Method (AFEM). It is corresponded to the increase of load and the ideal failure model of structure. AFEM uses the additional design diagrams and additional finite elements (AFE) for this operation. This process is illustrated by the transformation of design diagram of bended concrete console from the beginning of its loading to the collapse. The structure reveals four physical nonlinear properties before the ultimate limit state. Every nonlinear property appears under the action of corresponded load. The stiffness matrix and the set of equations are changed under influence of the value of load and the presence of observed nonlinear properties at this moment.