Analysis of ring pressure distribution on a deformed cylinder face

Elastic properties of correctly designed piston compression ring should provide full contact of ring face and the cylinder surface. Actually, because of various phenomena and processes experienced during engine assembly and operation an initially cylindrical liner is being subjected to wear and deformations which eventually affects that contact and cause formation of slots distributed along the cylinder circumference. Following paper describes the most often met deformations of cylinder and presents an evaluation of their influence on the process of compression ring collaboration with the surface of misshaped cylinder. Mathematical relations that allow to calculate the change of ring cylinder pressure and location of areas where blow-by can occur have been presented as well. The presented analyses were supplemented with charts illustrating changeability of certain quantities characteristic for ring and liner construction, using a marine engine ring as an example. The relations established during investigation will be used for a construction of mathematical model of phenomena accompanying the operation of piston-cylinder assembly elements, in the subject of blow-by in particular.