Experimental Analysis of Local Stress State and Deformation in the Critical Area of Combustion Engine Cylinder

Abstract

The article is focused on local stress simulation as well as local deformation analysis in a cylinder of piston combustion engine. Design of the exhaust pipe system has to fulfill special requirements with regard to the combined loading due to high pressures and temperatures. There is a special role of the exhaust pipe barrier, which is situated in the exhaust gas pipe. This barrier separates the main air hole from the secondary lateral auxiliary air holes. The exhaust pipe barrier seems to be a critical point of the cylinder. The finite-element analysis applied on the silumin-cast cylinder is presented in the paper in order to prove the critical places with high stress concentration. The local strength of the cylinder material was estimated using a material model based on relation between the strength and the mean distance between the secondary dendrite arms (SDAS) in the as-cast microstructure. Due to local heterogeneities there are differences in the local strength value at the various places of the microstructure. The simulation of stress distribution was performed by use of the finite-element method. Based on the relation „local stress/local strength“ the individual critical places in the cylinder were defined and located.