Operational conditions of vehicles motion and formation of urban driving cycle in the city of Lviv
Date
2017-01-01
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Lviv Politechnic Publishing House
Abstract
To the greatest extent, the indicators of the motor vehicles being in the normative technical
state are influenced by the operational conditions, which, in turn, are characterized by road, relief (terrain)
and transport conditions. The transport conditions of large cities of Ukraine are characterized by the
intensive increase of motor transport, especially individual (private) one, on the street-road network of the
city caused a number of problems, such as increased waste of time needed for a trip, increased number of
forced stops, increased number of emergencies and road-traffic accidents, the occurrence of traffic jams,
chemical and noise pollution of the environment. As the special investigations indicated, the volume of
traffic has increased by 1.5…1.8 times in comparison with the data of ten years ago [1]. All this caused the
necessity to substantiate the rational use of the power of the motor vehicles engines and to control their
ecological indexes in order to reduce the negative influence on the environment.
While evaluating the toxicity of the motor vehicles engines, two fundamentally different methods
of investigations are being used: testing on steady-state operating conditions with constant parameters
of the engine and testing on transient operating conditions when the input parameters are being
changed. For the transient conditions, the main conditions of the motor vehicles motion have been
identified: motion in the conditions of the city and motion out of its borders. Each of the conditions
is characterized by the differences in the percentage of toxic components in the exhaust (burnt) gases.
While developing the technique of determination of ecological indexes and parameters of fuel
economy (saving) for motor vehicles, a large number of factors, which varies depending on the
operating conditions, are considered. This is expedient in the case when the operating conditions are
very different considering the typical motion conditions in the region and the several aspects that
affect the fuel consumption. One of the main reasons for this is the unsatisfactory state of planning,
accounting and standardization of the efficiency of the motor vehicles use. In this approach, the
operation indexes are estimated based on not always impartial reporting and statistical data, so the
standards are not an impartial factor or a model for the motor vehicles operation. These
circumstances substantiate the urgency of the subject of research.
While carrying out these investigations, the preliminary analysis of the motion conditions of
the motor vehicles in different operating conditions is conducted and the peculiarities of the existing
driving cycles of different countries of the world are considered.
In order to ensure the determination of the motion conditions of motor vehicles in the conditions
of the city of Lviv, the technique of investigations carrying out was developed on the basis of available
means. The results of changing the conditions of the motor vehicles motion in the conditions of the
city of Lviv were obtained taking into account the motion speed of the motor vehicle, the rotation
frequency of the engine crankshaft, the instantaneous fuel consumption and the amount of consumed
air. According to the results of the experiments carried out, the main features of the operational
conditions of motor vehicles motion in Lviv were determined, the driving cycle for testing the motor
vehicle in the conditions of Lviv and the method of comparative analysis of existing and improved
driving cycles were developed. The analysis of indexes of existing and developed driving cycles is
carried out and the expediency of use of the developed driving cycle is substantiated.
Description
Keywords
operational conditions, motor vehicle, driving cycle, comparative analysis, fuel consumption, motion speed, rotation frequency
Citation
Kachmar R. Operational conditions of vehicles motion and formation of urban driving cycle in the city of Lviv / Roman Kachmar, Juriy Vasyuhnyk // Ukrainian Journal Of Mechanical Engineering Andmaterials Science. — Lviv : Lviv Politechnic Publishing House, 2017. — Vol 3. — No 1. — P. 117–124.