The feasibility of determining the condition of friction units of engines by the EMF magnitude

The paper is devoted to theoretical studies of the feasibility to determine the clearance size in the friction units of an internal combustion engine by the magnitude of the electromotive force (EMF) that arises in them. The effect of the contact area of the friction pairs and the clearance between them on the electrical resistance in the contact, and, accordingly, on the magnitude of the emerging EMF was theoretically confirmed. As a result of the theoretical studies, the relationship of the influence of changing clearances on the magnitude of the EMF arising in them was established. To confirm the theoretical calculations, bench studies of the UMZ-417 engine were carried out to determine the magnitude of the EMF arising in its friction pairs depending on the change in the crankshaft rotation speed, followed by micrometry of the parts. The study was carried out using the designed current collector. The obtained theoretical and experimental results confirm the feasibility of determining the condition of friction units by the magnitude of the EMF generated in them and with sufficient accuracy to determine the dynamics of the clearance size between rubbing parts