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In connection with the tightening of environmental standards, the leading manufacturers of marine low-speed engines are carrying out intensive work on their conversion to gas fuels. Due to the design features in this class of engines, only internal mixture formation is possible. For the organization of which two different approaches are possible. To date, only two are currently implemented. MAN started production of engines with gas fuel supply to the working cylinder under high pressure at the end of the compression stroke, and WinGD under low pressure at the beginning of the compression stroke. The analysis, performed by the authors, showed, that increasing the pressure before the gas supplying mechanisms to 3.5...6.0 MPa can reduce the residence time of the gas-air mixture in the working cylinder and reduce the likelihood of detonation combustion.

The article is devoted to the study of the efficiency of the system that provides the production of hydrogen-containing gas using a thermoelectric generator and the addition of this gas to the air charge of the spark ignition engine to improve its indicated, effective and environmental performance. The thermoelectric generator is installed in the engine exhaust system and provides the conversion of the exhaust gas thermal energy into electrical energy to power the generator of the hydrogen-containing gas. The results of experimental studies of indicated, effective and environmental performance of the engine with the hydrogen-containing gas added in a wide range of operating modes are provided. Vehicle fuel economy and environmental performance with the developed system for adding the hydrogen-containing gas are forecasted using a mathematical model of the car motion in the driving cycle.

This article describes experimental research results of the electropneumatic clutch control device for the mechanical transmission. The aim is to assess electropneumatic clutch control device characteristics to regulate both mechanical and robotic transmission. The feature of the clutch control system having the electropneumatic actuator on the basis of a power cylinder is the use of a control module that consists of an acceleration valve and two electropneumatic valves. A new structural relationship between the electropneumatic clutch control device elements on the basis of the new acceleration valve design is suggested. The assessment of mass and dimension parameters of well-known devices and this electropneumatic clutch control device is provided. A new approach to choose automated clutch control system parameters taking into account the relay electropneumatic control system operation features is suggested.

The article deals with the results of experimental and theoretical studies of the technological vehicle during its work on various types of fuel. The purpose of the work is to choose a rational type of fuel or an energy source for vehicles according to one general criterion. The feature of the proposed methodology is that the indicators of fuel and engine are estimated by the criterion of adaptability of technique to a particular type of fuel. A new approach to environmental safety assessment of technological vehicles while working on different fuels by environmental criterion taking into account the amount of emissions of harmful substances, their maximum permissible concentrations and hazard class. The economic efficiency in the operation of vehicles on alternative fuels is estimated by the criterion of economic efficiency.

The article discusses the features of designing a diagnostic system in which harmonic analysis is used to improve the quality of diagnostic information processing. The cyclic analog signal coming from the sensor and containing the diagnostic information is converted into a discrete signal. Accumulation of diagnostic information processed by equipment is carried out in the form of discrete signals. The processing and analysis of the obtained diagnostic information is carried out by applying harmonic analysis. Periodic processes of operation of vehicle units are associated with the occurrence of noise and vibration having a different frequency but related to the same node. A feature of the presented system is that it uses a contactless method of obtaining diagnostic information about the operation of vehicle units. The system calculates the speed of the node, measures the noise level and calculates the level of vibration that occurs during its operation.

The article deals with the analysis of one of the methods of selecting rational parameters of automated clutch control system for robotic transmission. The objective is to select rational parameters of automated clutch control system for robotic transmission, equipped with electropneumatic actuating mechanism on the basis of mathematical simulation. The depicted mathematical simulation of the clutch control system is characterized by the possibility to coordinate the algorithm of control unit with the dynamic processes in the execution device. The new functional interrelations between the elements of the electro-pneumatic actuator are mathematically described. The way to the selection of rational parameters of an automated control system for clutch is recommended; the selection taking into account the features of the electro-pneumatic actuator. Using the mathematical modeling method, rational control parameters of the automated clutch control system are determined.

The paper describes the process of modeling and optimizing the operating conditions of vehicles for a section of the transport network using simulation tools. The cyphergrams of the transport flow intensities in the transportation hub were built, a graphic model of vehicle traffic in the transportation hub was built, and a transition probability matrix was compiled, which was used to simulate modeling and optimize vehicle operating conditions for the considered transport hub. It is necessary to use simulation modeling software that supports all simulation methods and a powerful built-in library for traffic modeling. The corresponding simulation model was created. With the help of it, modeling in the transport hub selected for research has been carried out and the optimum values of the duration of the phases of traffic light objects have been obtained. It has reduced the average travel time through the site, which is considered in the work, and the number of cars in traffic jams.

The utilization of different types of energy in phase-transitional thermal accumulators and its further use for thermal development of different subsystems of hybrid vehicles enables to significantly increase their operational efficiency. The system of the combined utilization of thermal and electrical energy in phase-transitional thermal accumulators (TA) is offered. To charge TA, it uses thermal energy of exhaust gas, a coolant and motor oil of the internal combustion engine and electrical energy which is utilized by energy recovery system when braking the vehicle. It consists of consecutive stages of heat accumulation when charging TA from different energy sources of the hybrid vehicle, its storage and use for rapid heating of vehicle separate subsystems. The main heat and power characteristics of system components and heat accumulating materials used in phase-transitional TA have been justified.

The article suggests the results of experimental and theoretical studies of the engine heating system with a phase-transitional thermal accumulator when the vehicle is in motion in a driving cycle. The aim of the study is to evaluate the efficiency of the vehicle heating system within thermal accumulator and catalytic converter under operating conditions. The peculiarity of the presented system is that it uses thermal energy of exhaust gases to accumulate energy during engine operation. The article describes the methodology to evaluate vehicle fuel consumption and emission in the driving cycle according to the UNECE Regulation № 83-05. The methodology takes into account the environmental parameters, road conditions, the design parameters of the vehicle, the modes of its motion, thermal state of the engine cooling system and the catalytic converter.