MODERNIZATION OF THE LUBRICATION SYSTEM OF THE TURBOCHARGER BEARING OF THE DIESEL ENGINE

The problem of increasing the unit power of the engine without making changes to its design is solve by using a turbo supercharger. However, due to the intensity of the turbochargers operating mode, which are characterized by engine speed variability due to changing load indicators during operation (the number of rotor revolutions varies from 30000 min-1 to 120000 min-1, engine exhaust gases have a temperature of about 7500C), there is a need to improve the efficiency of the turbocharger bearing lubrication system. The purpose of the research is to ensure the operability and increase the reliability of turbochargers of diesel engines. To achieve this goal, a constructive solution for the lubrication system of the bearing assembly was propose, i.e., a membrane-type hydraulic accumulator was structurally provided in the lubrication system of the bearing assembly. Experimental studies were conduct to identify the operability and effectiveness of this constructive solution. The experiment was carried out on the KAMAZ-740 engine, the turbocharger shaft drive was carried out in normal mode, that is, from exhaust gases. L-02-40 fuel was use, SAE 10W–40 API was use as a lubricant. The turbocharger shaft speed varied from minimum to maximum by changing the engine speed and then stopping it. During the experiments, the following parameters of the turbocharger operation were measure: the duration of inertial rotation of the turbocharger rotor; the duration of pressure reduction in the turbocharger lubrication system. The dependences of the influence of the duration of the pressure drop in the turbocharger lubrication system and the duration of rotation of the turbocharger shaft by inertia with parallel inclusion of the accumulator in its lubrication system and in the normal mode of lubrication of the bearing are reveal. It is established that the installation of a device for feeding the turbocharger bearing during a sharp reduction in engine speed will increase the run-out of the turbocharger rotor from 30 to 65 s while maintaining the normal operating mode of the turbocharger lubrication system

Innovative solution of hybrid hydraulic fire wood splitting machine

Hybrid powertrains have already proven themselves as viable solutions for reducing fuel consumption while maintaining the same operating performance of conventional ones, which is achieved by using an additional energy source in combination with energy recuperation. Many forestry machinery and tools which are intended for field use are hydraulics-based and powered by tractors or skidders. These tools may also be hybridized by incorporating a properly-sized hydraulic accumulator. This paper proposes an innovative solution of hydraulic fire wood splitting machine which uses a hydraulic accumulator in order to increase its efficiency. A simple model of conventional and hybridized machine is developed and presented in this paper. The model is then simulated over a defined operating cycle with realistic loads. Simulation results show that hybrid structure may improve the splitting performance with lower power requirements. Finally, the conventional and hybridized machine performances are compared and discussed.

Modelling and experimental validation of the performance of a digital displacement® hydraulic hybrid truck

The development, modelling and testing of a novel, fuel-efficient hydraulic hybrid light truck is reported. The vehicle used a Digital Displacement® pump/motor and a foam-filled hydraulic accumulator in parallel with the existing drivetrain to recover energy from vehicle braking and use this during acceleration. The pump/motor was also used to reduce gear-shift times. The paper describes the development of a mathematical vehicle model and the validation of this model against an extensive testing regime. In testing, the system improved the fuel economy of the vehicle by 23.5% over the JE05 midtown drive cycle. The validated mathematical model was then optimised and used to determine the maximum fuel economy improvement over the diesel baseline vehicle for two representative cycles (JE05 midtown and WLTP). It was found that the hybrid system can improve the fuel economy by 24%–43%, depending on the drive cycle. When this was combined with engine stop-start, the system improved the fuel economy of the vehicle by 29%–95%, depending on the drive cycle.

Technical Solutions of Forest Machine Hybridization

The paper deals with the characteristics of three different types of power train hybridization of forest logging machines and with the benefits of reducing environmental impacts by comparing new technology with more conventional, older technology. New hybridization options that could be implemented in forestry machines are also discussed. The paper divides a hybrid solution into three classes based on the energy used in the system of hybridization. First is an electro-hybrid system that uses an electric motor and battery or different storage device. The second, a hydraulic hybrid system, is a solution with a hydraulic accumulator, hydraulic motor, and pump. The third system is a combination of the electro-hybrid and hydraulic-hybrid system. The current technical and technological development of hybrid drive systems, as well as their components, has led to significant improvements in drive performance and thus better performance of the new generation of forest vehicles. Improved energy efficiency using hybrid propulsion systems in forest vehicles would result in a significant reduction in greenhouse gas emissions and possibly lower maintenance costs.

Investigation of transient processes of blade movement of compacted snow vibrocleaver

The lack of the necessary amount of equipment for winter maintenance, significant precipitation in the form of snow, lead to a decrease in the efficiency of roads. Inside, courtyards and sidewalks are also covered with a layer of compacted snow due to untimely snow removal. Mekhanic method of breaking compacted snow is currently insufficiently studied and so far there is no effective equipment to combat snow and ice formations. A peculiarity of the process of compacted snow destruction in the mode of vibration cutting is intermittent contact of the knife with the destroyed medium. Condition of the set mode of vibrocutting is the criterion of an exit of a blade of a vibrocleaver from contact with the destroyed environment. The aim of the study is to establish the time at which the knife comes into contact with compacted snow. The obtained results of the calculations make it possible to set the values at which the mode of «vibration cutting» is set and to select parameters of the hydraulic accumulator, which ensures the movement of the blade of the vibrocleaver of the compacted snow.

ENERGY-EFFICIENT TECHNICAL SOLUTIONS FOR THE OPERATIONAL CHARACTERISTICS OF THE HYDRAULIC DRIVE OF THE TRACTOR

During the movement of the tractor on the uneven terrain, there are fluctuations that cause jumps of the working fluid in the hydraulic system and high dynamic loads. The solution to this problem is the use of an energy-saving hydraulic drive with a hydraulic accumulator and a system of aggregates this leads to increased efficiency and increased productivity of skidding grippers. A mathematical model of working processes with an energy-saving hydraulic drive is compiled.

An Estimation of Hydraulic Power Take-off Unit Parameters for Wave Energy Converter Device Using Non-Evolutionary NLPQL and Evolutionary GA Approaches

This study is concerned with the application of two major kinds of optimisation algorithms on the hydraulic power take-off (HPTO) model for the wave energy converters (WECs). In general, the HPTO unit’s performance depends on the configuration of its parameters such as hydraulic cylinder size, hydraulic accumulator capacity and pre-charge pressure and hydraulic motor displacement. Conventionally, the optimal parameters of the HPTO unit need to be manually estimated by repeating setting the parameters’ values during the simulation process. However, such an estimation method can easily be exposed to human error and would subsequently result in an inaccurate selection of HPTO parameters for WECs. Therefore, an effective approach of using the non-evolutionary Non-Linear Programming by Quadratic Lagrangian (NLPQL) and evolutionary Genetic Algorithm (GA) algorithms for determining the optimal HPTO parameters was explored in the present study. A simulation–optimisation of the HPTO model was performed in the MATLAB/Simulink environment. A complete WECs model was built using Simscape Fluids toolbox in MATLAB/Simulink. The actual specifications of hydraulic components from the manufacturer were used during the simulation study. The simulation results showed that the performance of optimal HPTO units optimised by NLPQL and GA approaches have significantly improved up to 96% and 97%, respectively, in regular wave conditions. The results also showed that both optimal HPTO units were capable of generating electricity up to 62% and 77%, respectively, of their rated capacity in irregular wave circumstances.