Multi-body numerical simulation of the distribution drive system in an internal combustion engine

V clanku je predstaven vyvoj metodiky pro vypocet dynamiky mechanismu motoroveho rozvodu. Vyuzity jsou techniky simulaci vicehmotovych soustav; pouzit byl software AVL/Tycon. Objektem vyzkumu byl vliv pracovnfho rezimu motoru na dynamiku retezoveho rozvodu s jednim (SOHC) a dvema (DOHC) vackovymi hndeli v hiave motoru. Analyza obsahuje dukaz, ze retezovy prevod zavadi (di'ky kinematickemu zaberu) vysokou frekvenci s velmi malou amplitudou v porovnani s harmonickymi frekvencemi od externi sil. Metodika umozhuje urdt zati'zeni vstupni'ho a pomocnych hridelu, zatizeni na strukturu motoru indukovane pres operne a napmaci kladky. Diky tomu se predstavena metodika stava vyznamnym nastrojem pro predvidani zatizeni; a navic umoznuje i detailni vypocet trecich ztrat v jednotlivych castech retezoveho rozvodu.

The purpose of the present work is the development of a methodology to study the dynamic behavior of the drive distribution system, based on the techniques of multi-body numerical simulation using AVL/Tycon code. Chain drive systems with both single cam shaft (SOHC) and double cam shaft (DOHC) are studied to investigate how the dynamic behavior varies with the engine working rate. The analysis includes evidence that the chain transmissions introduce a high frequency due to kinematic engagement (polygon effect), with a very low amplitude with regard to the harmonics of external forces. The methodology permits the evaluation of the loads on the drive shaft, on the distribution shafts, and loads acting on the engine structure through the supports and constraint points. It represents an important forecasting tool; moreover, it also permits the detailed calculation of the friction lost in the interaction between the chain components.