SOME ASPECTS OF IMPROVING OF ICE OUTPUT PARAMETERS DURING MODERNIZATION IN THE CONDITIONS OF SERIAL PRODUCTION

The analysis of the features and methods of modernization of serial internal combustion engines was carried out in order to increase the output parameters. With specific examples, it is shown that the desire of engine manufacturers to improve performance while minimizing costs often leads to an unreasonably high risk of uncontrolled changes in the loads on parts, when after upgrading the quality and reliability of products deteriorates. At the same time, the most dangerous variants of modernization should be considered the so-called scaling, which produces a slight increase in output parameters while maintaining the same structure and geometry of the main parts, which is usually done without necessary research and testing or, at least, without modeling loads on parts the purpose of determining the critical sections and their possible amplification. Examples of modernization of engines by increasing the size of parts and increasing the boost pressure, as well as its consequences, causing various damage and destruction of the main parts, which is associated with exceeding the permissible level of loads, are done. In order to prevent a reduction in the reliability of upgraded production engines with the exclusion of unnecessarily high costs, an assessment was made of possible ways of modernization. A general approach to modeling the loads on the main parts of the upgraded serial ICE is proposed, the main results of modeling the stress-strain state of the piston, piston pin and connecting rod are given. Data were obtained to identify dangerous sections in which locally high stresses are observed, which increase the risk of fatigue failure of parts with increasing loads. Based on the results obtained, recommendations were given on the practical application of a computational experiment when modernization of serial ICEs