Application of test method in environmental monitoring of catalytic converters

Due to the tightening emissions regulations for vehicles, the exhaust system is being equipped with additional components to maintain the required emission levels, such as an exhaust gas recirculation (EGR) system, catalytic converter (CC), diesel particulate filter (DPF), and so on. The introduction of these additional elements in the exhaust system affects the operating conditions and modes of internal combustion engines (ICE). However, the process of diagnosing the CC wear level is complicated due to multiple interdependencies between structural and diagnostic parameters. These interdependencies are formed during the gas exchange process between the intake air, fuel-air mixture in the cylinder, and exhaust gas, and involve a range of physical relationships that determine these interdependencies. Gradual wear of the catalytic converter leads to increased backpressure in the exhaust system due to the formation of surface deposits, melting and destruction of ceramic cells, which increases mechanical losses and reduces engine efficiency. This article presents a test method that enables continuous monitoring of the technical condition of the catalytic converter and accurately identifies its changes. The theoretical part of the study discusses the methodology for calculating the resistance of the catalytic converter, taking into account the influence of resistances in the porous volume, thermal resistance, and material structure resistance. The experimental work analyzed the data obtained from the interaction of only two input parameters: injection duration and equivalent resistance of the catalytic converter.