Design of microsupervisory controlled congestion indicator circuit for dry air filters in internal combustion engines

The main purpose of using air filters in internal combustion engines is, to hold the pollutives in the air and to prevent parts of the engine from possible deteriorations. Since becoming dirty period of the air filter is not proportional to the distance gone by the vehicle and the duration of running but to the pollutive ratio in the air, it is important to determine the dirtness of the air filter on time. In this study, a circuit which determines the congestion of the filter by means of two pressure sensors controlled with a microcontroller (PIC) is designed. Beside these the effects of air filter surface area on filter exit pressure, the air flow of the engine, volumetric efficiency and turbo pressure are investigated and the results of experiment are given with graphics.Key Words : Air Filters, Microcontroller, Congestion indicator Of Filter, Air Flow