Reliability analysis of connecting rod in two-stroke aviation piston engine
LI Yi
Abstract：To study the reliability life of a two-stroke aviation piston engine connecting rod under cyclic loading,a connecting rod group analysis model is established using finite element software.The contact types between the internal parts of the connecting rod assembly are reasonably set,and stress distribution calculations are carried out based on the connecting rod assembly condition,maximum compression condition,and maximum tension condition.The material S-N curve method and Gerber average stress correction model are used to evaluate the high cycle fatigue characteristics of the connecting rod,and the safety factor of the connecting rod under different loads is obtained.A 150 h durability test is conducted on the entire engine equipped with the connecting rod.The stress and high cycle fatigue calculation results show that the static strength of the connecting rod under three working conditions meets the design requirements,and the contact stress can ensure reliable connection between internal parts.In a working cycle consisting of three typical operating conditions,the minimum fatigue safety factor of the connecting rod is 1.33,and the fatigue safety factor meets the design requirements.After the durability test,the dismantling inspection results show that there are no cracks in the parts,and the wear,gloss,scratches and other defects on the friction surface meet the evaluation standards,the key dimensions and positional tolerances of the connecting rod also meet the design requirements.
Keywords：finite element methodaviation piston enginepenalty function methodequivalent stressfatigue analysis
Publication Date：2025-03-30
Online Publishing Date：2026-05-22(First online date of this platform, not the publication date of the document)
Pages：7( 60-66 )