Abstract:

Based on the performance of real experiments and measurements, the article analyses the changes in the performance and environmental parameters of the internal combustion engine in case of failure of any of the systems for reducing the amount of harmful emissions.
Training and research stands of diesel and gasoline engines have been developed in the laboratory of internal combustion engines at the Faculty of Physics and Technology of Plovdiv University "Paisii Hilendarski". They have been used in the process of practical training of students majoring in "Automotive Engineering".
The training focuses on the complex structure of the EGR, the lambda probe, the catalyst, and the DPF particulate filter, which ensure the reduction of harmful emissions.
The training methodology examines in detail the exhaust gas recirculation (EGR) system, which serves to reduce nitrogen oxides in the exhaust gases by returning some of the gases to the intake manifold. The operation of the lambda probe, which is an oxygen concentration sensor is also analyzed. The information from it is used by the fuel controller to dose the amount of fuel in the fuel-air mixture in order to ensure its complete combustion. The principle of operation of catalytic converters (CAT) is stated. They are designed to convert the harmful components of the exhaust gases emitted by internal combustion engines into harmless gases by chemical reaction. Therefore, the catalytic converter is an important part of modern emission purification systems for SI and diesel engines.
All modern diesel vehicles have a particulate filter, commonly called a DPF. As a rule, it is installed after the catalyst and is a ceramic briquette of porous structure weighing from 1.2 kg to 6 kg (depending on the vehicle). Its purpose can be seen from the name - retention of soot particles, flue gases.
Different systems may have different numbers of components, but the thing they all have in common is that faults can be either mechanical or electronic.
In the process of practical training, a sequence of faults is realized. Diagnosis is made and the reasons for their occurrence and their consequences are analyzed. Then their systematization is performed. Specialized software that provides modern methods of diagnosing systems is available.
The proposed methods for teaching exhaust gas recirculation systems, which serve to reduce harmful emissions in exhaust gases increase students' motivation in engineering education. During the study process, students make a series of measurements.
The training of future engineers requires the use of various strategies and resources for teaching, training and support. The transformation of the learning process in a modern educational environment requires students to master methods of knowledge, among which are the combination of laboratory tests, processing of experiments and analysing the results all of which have a vital meaning. This strengthens their willingness to conduct and manage engineering research and present the results of experimental work.The developed skills can be applied in the educational process and research practice in other university engineering courses as well.
The training methodology proposed in this article will undoubtedly ensure the application of modern methods of diagnosing the systems. This will contribute to the obtaining of valuable information for all specialists and students majoring in "Automotive Electronic Systems" and related automotive fields.

Keywords:

Training, automotive electronic systems, emission reduction.