The release of every new design of automotive products requires extensive durability assessment processes to guarantee safety and performance over the entire life of the vehicle. This process is mainly carried out experimentally and has traditionally major disadvantages such as large costs, long durations and a requirement for a large number of prototypes. CAE tools have been introduced in the design process in order to make durability predictions before prototyping.
However the poor quality of such fatigue life predictions for the mechanical components and the difficult and time consuming use of the tools are still critical factors which prevent systematic applications in the design processes and the achievement of the full benefit in terms of time to market. The new scenario of Low Weight vehicles and the pressure from the market to cut down development costs and lead time create the need for a substantial step forward. The present project has then three general objectives:
to introduce durability predictions in the concept or early design phase of innovative vehicle suspension components
to develop integrated CAE tools for early and realistic (robust vs manufacturing) co design with the suppliers .
to design simplified and accelerated tests on components through the use of CA analysis tools.
The technical objectives and the related developments of this proposal are the following:
to improve the state of art quality of CAE prediction by :
selection and validation of multi axial FLP criteria spot weld FE modelling and validation material data base including the effects of manufacturing on fatigue properties
to increase CAE tools integration creation of user interfaces (MB to FEM to FLP)
to improve the efficiency of durability assessments under complex multi axial load conditions by : strategies for synthesizing load histories (input for testing & numerical simulations) strategies for reducing FEM stress analysis output (focus on critical areas) to design simplified and accelerated fatigue tests on isolated components, through CA analysis, by determination and validation of appropriate boundary conditions
to demonstrate the feasibility of the integrated procedure and the related benefits on real case studies by multiobjective
(weight,fatigue life,..) design optimizations of components.
In order to compare the results obtained by different end users, a common mission profile will be defined and used as a reference for the fatigue life assessments within the project.
The final results will be a prototype SW package allowing the designer to run a complete and integrated numerical fatigue assessment of a suspension component, case studies producing Optimised demonstrators of suspension components aiming at 20% weight reductions, and finally simplified fatigue test procedures on the isolated components aiming at shortening the testing durations by a target factor of 10. The consortium comprises two car manufacturers, with complementary expertise and products, strongly committed with the development of innovative vehicles that will act as final users and validators respectively for the applications on thin shell and spotwelded components, an industrial R&TD center with consolidated technical and scientific experience in fatigue field that will act as developer of the engineering methodologies and validator on cast and forged applications, two suppliers of automotive components that will contribute with prototypes and technological expertise, two vendors of specific commercial engineering tools that will implement and integrate the methods into prototype Sw and finally two research institutions providing scientific support to the development of the spot weld models and the multi axial FLP criteria respectively.
Funding SchemeCSC - Cost-sharing contracts
CV35 0BL Warwick
10022 Carmagnola Torino