On the developing of the mathematical model of all-wheel drive vehicle

The mathematical model of all-wheel-drive vehicle is proposed, which makes it possible to investigate the economic indicators of the vehicle’s movement for choosing the optimal type of central differential in a given range of road conditions

On the developing of the mathematical model of all-wheel drive vehicle

The mathematical model of all-wheel-drive vehicle is proposed, which makes it possible to investigate the economic indicators of the vehicle’s movement for choosing the optimal type of central differential in a given range of road conditions

Acoustic pressure contributions of a combine harvester’s thresher drum to the overall workplace noise situation

This paper analyzes the magnitude of the acoustic pressure contribution of a combine harvester’s thresher drum to the overall noise situation with the goal of providing the regulatory parameters for the workplace conditions. In the course of the current research the velocity and pressure graphics for the airflow on the parts of a rotating thresher drum as well as the sound intensity parameters by frequency spectra and sound pressure magnitudes were calculated

Coal Industry Impact on Ants of the Genus Formica (Hymenoptera: Formicidae)

The peculiarities of the settlement of ants of the genus Formica have been studied at the areas affected by varying degreesof impact made by enterprises of surface (opencast mines) and underground (deep mines) coal hard mining. It has been revealed that Formica ants. str. are the most sensitive to any impact and in overwhelming cases disappear from the contaminated area. On the contrary, the representatives of Serviformica are more environmentally flexible, and are able to occupy areas with anaverage degree of contamination. However, the density of the settlement and the abundance remain low. After the cessation of coal mining near opencast mines, the recovery of myrmecofauna occurs more rapidly (7-10 years) than near deep mines (more than50 years). The higher the degree of contamination of the area, the lighter the colour of the ants. The proportion of insect larvae in the Formica rufa food sharply increases in the contaminated area

Heating system for measuring tanks of the cementing unit from the exhaust system of the base chassis

The purpose of this article is to increase the efficiency of the design process and reduce the cost of field experiments by using numerical analysis methods of the dimensional capacity heating efficiency of the internal combustion engine exhaust system. To solve the problem, a non-stationary nonlinear solver of gas dynamic processes (Siemens STAR-CCM+) was used, which allows to evaluate the correctness of the problem statement, significantly reducing the cost of full-scale tests. The paper considers the heating of a dimensional two-section tank in the layout of the cementing unit on the chassis with a triplex high-pressure pump and a drive from the power take-off box on the gear box of the chassis engine. The exhaust pipe structurally passes inside the measuring tank. According to the research results obtained graphic dependences of temperature change of liquid measuring cups to control points, the distribution of temperature field of the liquid in a volumetric tank, distribution of the temperature field of the surrounding air, stream lines and velocity field of the ambient air and the exhaust gases of internal combustion engines. The results of the calculations clearly show that the application of the method of heating the measuring capacity by entering the exhaust pipe directly into the liquid can be considered effective

Coal Industry Impact on Ants of the Genus Formica (Hymenoptera: Formicidae)

The peculiarities of the settlement of ants of the genus Formica have been studied at the areas affected by varying degreesof impact made by enterprises of surface (opencast mines) and underground (deep mines) coal hard mining. It has been revealed that Formica ants. str. are the most sensitive to any impact and in overwhelming cases disappear from the contaminated area. On the contrary, the representatives of Serviformica are more environmentally flexible, and are able to occupy areas with anaverage degree of contamination. However, the density of the settlement and the abundance remain low. After the cessation of coal mining near opencast mines, the recovery of myrmecofauna occurs more rapidly (7-10 years) than near deep mines (more than50 years). The higher the degree of contamination of the area, the lighter the colour of the ants. The proportion of insect larvae in the Formica rufa food sharply increases in the contaminated area

Determination of technological parameters and tool for flanging holes from sheet blanks

In the article the parameters of shaping operations of internal axisymmetric cylindrical flanging are considered. The article is written to improve the quality and speed of flanging round holes development from sheet blanks and tooling construction by increasing the accuracy of hole diameter calculation for flanging in the automated mode of building three-dimensional models of workpiece and a flanged product. Given formulas increase the accuracy of hole diameter calculation for flanging, taking into account the deformed condition of the sheet blank. The accuracy of the hole diameter calculation for flanging according to the given formulas is determined by comparing the mass of the workpiece with the mass of the flanged part. CAD system algorithm for automated construction of the flanged parts sketch and determination of technological parameters is implemented. The parameterized scheme of a typical construction of a flanging stamp is presented. The constructed schemes allow making changes in their parameters and providing automatic representation of calculation results and also their correct graphic interpretation. Discussion of the article results allows drawing conclusions about correctness of the given mathematical model and its applicability for the automated construction of three-dimensional models of the flanged details that will allow simplifying technological development and constructed documentation with simultaneous increase of their accuracy and reducing costs of production preparation

The efficiency is a single criterion for choosing the type of interaxle drive

The efficiency is proposed as a single criterion for choosing the type of interaxle drive. Dependence of efficiency on road conditions is shown. On the basis of the proposed approach, the opportunity to select the type of interaxle drive by comparing the quantitative indices, while analyzing the entire range of road conditions, was demonstrated

Impact of the vibrocathode on the patterns and properties of electrolytic copper powders

Methods for obtaining ultrafine copper powders from the etching waste of the printed circuit boards are described. Modes of obtaining copper powder in the anode-synthesized chloride-ammonium electrolyte using vibrocathode that allows intensifying the process as compared to the similar one at the stationary cathode by reducing diffusion layer are described. The productivity of copper powder obtaining in the offered terms is 0.25 g/(cm2·h), mean particle size is 3-4 microns. High efficiency of the process compared with the use of sulphate electrolytes, and a positive effect of the shape and size of the obtained copper powder on the processes of alloying Fe-based materials are reported. Properties of the antifriction materials doped with the obtained cathode copper powder in comparison with the materials alloyed with the PMS-1copper powder are considered. The effect of the working properties improvement of the samples doped with copper powder obtained from a copper-ammonium solution is observed

Influence of differential with the limited gear ratio on the efficiency reflecting losses on wheel slip

At vehicle movement, there are two factors that specify conflicting requirements for transfer box drive and axle drive. Let’s describe them: each wheel rotating at different speeds and reduced adherence of one or more wheels. The road conditions: the decrease in friction and kinematic disparity, acting often at the same time, present conflicting requirements to drive of the driving wheels. These factors tend to be of time-varying nature. The nature of the studied processes is transient; it will be influenced by the inertia, stiffness and damping properties of the vehicle power train parts. The efficiency reflecting losses on wheel slip is proposed as a uniform selection criterion of an interaxial drive. Based on comparison of dependence of this parameter on road conditions, higher efficiency of differential with limited gear ratio compared to simple differential and blocked drive is shown. The chosen approach on the basis of quantitative indices proves the efficiency of differential with the limited transfer ratio in comparison with other main types of the drive, such as differential and blocked