文档介绍：Advanced Numerical Simulation Techniques for
the Fatigue and NVH Optimization of Engines
Erich Payer
K+P GmbH, Schönbrunngasse 24, A – 8043 Graz
Tel.: +43 / 316 / 32 82 51, Fax: +43 / 316 / 32 83 51, E-Mail: office@
Abstract
Due to increasing government regulations concerning the emissions of vehicles (air polution and
noise), the necessary reduction of oil and raw material consumption and customer requirements -
sound engineering etc. - the automotive industry more and more is forced to optimize the NVH
behaviour of engines and to reduce the vehicle weight. Anyway these goals always have to be tightly
connected with the maintainance of the fatigue behaviour.
The use of numerical methods such as the finite element method (FEM) enables detailed information
about the static and the dynamic behaviour of structures to be determined during the development
stage /1/. It can be an excellent tool to analyze and optimize structures puter simulation and
therefore can help to reduce time and costs required for prototyping and to avoid numerous test series.
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1 Fatigue Analysis of Crankshafts
State-of-the-Art
Static finite element analysis of single crank throws are used for the basic evaluation of the stress be-
haviour due to maximum gas load, mass forces, and maximum torque loading cases, ,2,
considering a statically determined supporting.
Solid-Element-Model of a Crankshaft Section
Stress distribution due to ‘maximum gas load’
Nonlinear dynamic analysis
To approve the accuracy of those fatigue analysis K+P developed a method, , which is based
on inhouse developed software products. It enables numerical analysis of crankshaft dynamics and
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crankshaft loads which are very close to reality. Herein nonlinear effects in the bearings of the
statically undetermined supported, rotating, crankshaft as well as crankshaft dynamic effects such
as the fl