NVH Optimization of a 16-Cylinder Diesel Engine

Lothar Czerny; Markus Schwaderlapp; Thomas Wagner

doi:10.4271/932492

1993-09-01

NVH Optimization of a 16-Cylinder Diesel Engine 932492

In the early design stage a 16-cylinder V-engine is optimized with respect to its vibrational and acoustic behavior. The objectives of the development are: (1) to minimize vibrations of the crankcase with special focus on the structure-borne noise transmission via the engine mounts, and (2) in this context, to identify the appropriate locations for the engine mounts.

The NVH behavior of the engine structure is simulated using the Finite Element Method (FEM). The dynamic FE-model of the engine is excited via synthesized cylinder pressure force spectra. The corresponding vibrations of the sound emitting surface are calculated, thereby revealing structural weaknesses. By calculation of the crankcase modal vibrations, the noise relevant modes are identified. Based on these results the influence of structural modifications on the NVH behavior is predicted.

As a result of this work, structural modifications were defined that will lead to a decrease in vibration level of 4 dB in the frequency range between 300 and 1500 Hz. As for the position of the mounts, it was found to be advantageous to move them as far as possible to the upper engine block.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Digital $37.00 Print $37.00

Preview Document

We also recommend:

Standards

SAE Mobilus®

Publications

News

Events

Professional Development

A World in Motion (PreK-12)

Participate with SAE

SAE Membership

Donate

NVH Optimization of a 16-Cylinder Diesel Engine 932492

SAE MOBILUS