Analysis of fuel-saving properties of the car of the N1 class with the robotic step transmission on city routes.
Students Name: Podaiko Serhii Mykhailovych
Qualification Level: magister
Speciality: Motor Vehicle Transport
Institute: Institute of Mechanical Engineering and Transport
Mode of Study: full
Academic Year: 2020-2021 н.р.
Language of Defence: ukrainian
Abstract: Podaiko S. , Pelo R. (head of the master’s) Analysis of fuel-saving properties of the car N1 class with the robotic step transmission on city routes. Master’s qualification work. — «Lviv Polytechnic» National University, Lviv, 2020. Аdvanced abstract. In the domestic automobile industry, the need to move from a manual transmission to automatic transmissions has long arisen. As for the leading foreign manufacturers (Allison, ZF, Voith), their experience in designing automatic transmissions and the level of technological development is extensive. Recently, leading manufacturers of automatic transmissions are trying to reduce the use of torque converters, especially for small and medium-sized cars. However, the removal of the torque converter narrows the dynamic range of the gearbox, which inevitably leads to an unreasonable increase in the number of steps. In view of the relevance of the problems of energy conservation and environmental protection, presented in the work an analysis of standardized driving cycles. We studied various driving cycles, which are currently used in Japan, Europe, the USA, and Ukrainewhen determining fuel consumption. Based on the ICCT analytical report on a wide range of deviations of laboratory test results from actual driving conditions, it is concluded that it is possible to introduce a new WLTC driving cycle as a generally accepted standard for all car manufacturers. The dependence of fuel consumption on the average speed of the car is investigated. The method of development of normative driving cycles is analyzed. The analysis of the evaluation criteria, drive cycles and describes the main modes of motion of the vehicle, which are used in the simulation of the main international drive cycles. During the gear switching in the automatic automobile transmission with a dry frictional dual clutch the overlapping time factor on the one hand may reduce the switching time, but from the other hand it may also lead to the intense clutch slipping and as a result to the increased wear of the friction discs. The process of gears shift is so swift that the linear reproduction of «engine – transmission» system operation modes is quite natural and such that cannot distort the conception of optimal functioning of «engine – transmission» system. This paper analyzes the special features of the gear change process in the most common types of automatic gearboxes. Constructive feasibilities of an "ideal" gear change (without power loss) and strategies for gear shifting are compared. The automatic transmission is less energy-efficient (its performance index is generally lower) compared to the mechanical transmission, but due to the optimal combination with the engine and the implementation of optimal blocking laws for the hydrodynamic transformer, as well as the laws of gear shifting in its mechanical part, it is potentially capable of still sometimes provide higher fuel economy and dynamism of the car. And yet: the property of an automatic transmission to absorb shock loads contributes to an increase in engine resource and undercarriage. Objects of research: system "engine-robotic transmission-environment". Subject of research: recommendations on the choice of economic modes of operation of the system "engine-robotic transmission" of the car class N2 in the city. The purpose of research: with the help graph-analytical means to investigate the influence of the main operating conditions on the fuel efficiency properties of the car of class N1 under the condition of using a robotic transmission. Analysis fuel efficiency of vehicle acceleration with two types of transmissions: with conventional mechanical, with duo flow without breaking the power flow. Two modes of acceleration: acceleration from the start and acceleration on a straight road section after passing the curve have been considered. Keywords: robotic gearbox, gear shift, fuel consumption, driving speed, driving cycle.