No abstract

Currently, loosening and separating machines that combine the operations of crumbling and separating of soil according to the treated layer depth have come to the forefront. Interaction of the rotor blade of these machines with the soil comprises three stages: soil core formation; steady movement; and dumping of soil from the separating grid. The article determined the direction and magnitude of soil displacement, parameters and shape of the furrow formed after the ripper passage. Based on theoretical research, a mathematical model of the interaction of working bodies with the soil was developed. The initial data were obtained experimentally, and the model was justified. As a result, it was found that the supplied soil layer thickness and the fracture angle of ripper have the greatest influence on the transporting capacity of rotor ripper. Reducing the rotor blade entry angle into the soil from 45° to 30° made it possible to raise the second soil feed of the loosening and separating machine by more than 40 times. The width of rotor ripper practically does not affect the transporting capacity. Changing the angle of ripper entry into the soil allowed obtaining of the required transporting capacity of ripping and separating machine without changing the rotor design. Practical significance of the study lies in the possibility of increasing the work productivity without increasing its energy indicators.

The article schematically considers a proposal for development and application of a controlled power distribution mechanism for machines involved in timber industry and agriculture. Use of the mechanism will increase energy efficiency of skidder and forwarder on tractor chassis, improve steering quality of tracked vehicles and improve controllability of wheeled vehicles. For articulated vehicles, use of a controlled power distribution mechanism is expected to reduce stresses on swing mechanism. The article presents analysis results of literary sources on problem of using controlled power distribution mechanisms in transmissions of tracked and wheeled vehicles. Advantages of using such mechanisms in transmissions of tractors and forest vehicles on their chassis are shown. References are given to publications containing descriptions of mechanisms that are similar in characteristics to the developed one and known methods for determining main parameters of power distribution mechanisms, approaches to kinematic, force analysis and energy balance construction of such mechanisms. Kinematic diagram of a new controlled mechanism of power distribution is considered, main parameters, control technologies, and areas of its application are determined. Links between the project and currently developed capabilities of Russian production are outlined. Development prospects of technology for controlling distribution of power in transmissions of tracked and wheeled vehicles in the field of transport engineering are indicated. A reference is given to the research complex created and used at the Peter the Great St. Petersburg Polytechnic University, as allowing to conduct comprehensive tests of experimental models of transmissions of transport and traction vehicles.

No abstract

In recent years, the enterprises of forestry and the Ministry of Energy of the Republic of Belarus and other countries widely implemented advanced milling tools designed to chop wood, stumps and roots without immersing the cutter in the soil (mulchers) and with immersion (rotovators), which allows you to prepare the ground for planting forest crops. They can be mounted on multi-purpose tractors, loaders and excavators. At the same time, there are no methods that allow carrying out a reasonable choice of technological equipment for a particular basic machine, since a significant number of production, technological and technical factors have an impact on the emerging power and capacity parameters. The proposed method allows taking into account a significant number of variable values (working methods, speeds of various operations, parameters of the working body, its drive and base chassis, soil conditions, etc.) and simulate the interaction of milling tools under various operating conditions. It was found that the greatest loads on the mulcher rotor occur during the felling of tree and shrub vegetation, which is associated with an increase in the area of interaction between the cutters and the wood up to 2 times compared with the chopping of similar lying stands. This value can be reduced by 15–30 % depending on the diameter of the trunks being processed. In the case of a significant amount (cluster) of forest stands with a diameter of more than 10 cm, it is preferable to carry out work at a speed of about 0.2 m/s or advanced felling of these trees. The use of hydraulic travel (speed) reducers or hydrostatic transmission is promising in order to reduce dynamic loads and get better adaptability of the working equipment to natural-production conditions (the ability to work at a speed from 0 to 5 km/h). It should be noted that the installed required engine power for the milling equipment drive should be increased by 10–15 % due to the needs of the drive of various equipment located on the base chassis. Also, in the case of the integrated use of tree and shrub vegetation, it is possible to use mulchers that collect biomass; however, this will require additional energy costs. In this regard, the method can be applied when choosing the parameters of technological equipment for the existing base chassis, to solve the inverse problem, and also to select the operating mode of the milling equipment depending on the natural and production conditions with the possibility of subsequent prediction of the effectiveness of the work performed.

The article presents the results of theoretical research on the methodological provisions of the weight of the criteria in determining the technical level of agricultural machinery. The expediency of using relative, in parts of change, values of evaluation indicators, which allows to objectively and reliably obtain the value of the weight of the criteria in determining the technical level of agricultural machinery. The applied problem of determining the weights of the criteria in the study of the technical level of combine harvesters is considered. Five criteria are substantiated: reduction of direct costs, reduction of energy consumption, reduction of labour costs, reduction of material consumption, increase of reliability. The weight of the criterion reflects the degree of its importance in the rank of the sequence, their values are in the range 0…1. Five indicators are substantiated: operating costs, direct fuel costs, specific labour costs, specific material consumption, failure time. It is established that in the process of operation of the combine harvester Slavutich KZC-9M with a reduction of 30% of operating costs, the weight in determining the technical level is 0.1473. Studies have shown that a 25% reduction in direct fuel consumption is 0.1228 weight in determining the technical level of the combine harvesters.

No abstract

The problem of environmental pollution is one of urgent problems of mankind. This problem especially applies to large cities of any state. Atmospheric air, which performs life-supporting, protective and other functions, is subject to the greatest change. Increased air pollution leads to a negative impact on public health. So, every year number of social movements and various events is growing, expressing great concern about the state of air in the city of Bishkek. Basically, organizational and technical measures are aimed at improving road safety by reducing speed. But along with a decrease in traffic speed, fuel consumption increases, which in turn leads to a proportional increase in exhaust gas emissions. Especially in places where artificial irregularities are established, intensive braking occurs, followed by acceleration of the vehicle. This article is devoted to assessing the impact of unregulated pedestrian crossings on average speed of traffic and emission of harmful substances by vehicles. Relationship between the average traffic speedat unregulated pedestrian crossings and the total delay of vehicles has been established. An increase in emissions from vehicles at unregulated pedestrian crossings is substantiated, which makes it possible to calculate the cumulative emissions from vehicles on the sections of the city’s road network more accurately. This article presents the results of experimental studies of the influence of artificial irregularities, stopping points and parking places on the traffic speed and emissions of exhaust gases into the atmosphere.