Idealization, Measurement and Calculation of an Engine Block 820438
This paper describes static, dynamic, and acoustic finite element analyses of the engine block of a water-cooled 4-cylinder in-line engine, the results were later compared to measurements .
In order to locate the critical zones of the crankcase, a rather coarse general model was analyzed first, followed by detailed analyses of a number of subregions.
It was found that the results obtained from the idealized structure agreed quite well with static and dynamic measurements performed at the same time.
Static deformations found in the various zones yielded important information concerning the stiffness of the crankcase. By introducing a number of specific alterations it was possible to influence the stiffness of the crankcase, reduce stresses and decrease wear.
Dynamic analysis showed the prevailing natural frequencies as well as some information concerning those sections of the crankcase which are either suitable or unsuitable for attaching ancillary devices.
Further measurements were made to study the overall noise emission of the running engine, the dominant frequencies of sound, and the major causes of noise.
The acoustic behavior of a side wall of a crankcase together with some geometric variations was investigated by computing the sound intensity quotients.
Sound intensity measurements confirmed the results of these computations to a large extent.