No abstract

The JuliaFEM software library is a framework that allows for the distributed processing of large Finite Element Models across clusters of computers using simple programming models. It is designed to scale up from single servers to thousands of machines, each offering local computation and storage. The basic design principle is: Everything is non-linear. All physics models are non-linear from which the linearizations are made as special cases. This is a work in progress. Thus, if you share the vision, contribute and join the community.

Summary.A detailed contact analysis of a large connecting rod was performed to evaluate the fretting risk in the big end. Simulation was carried out in Abaqus considering all relevant boundary conditions, such as assembly loads, housing machining and dynamics from a flexible multibody simulation with elastohydrodynamic bearings. Being one of the most important variables, the local coefficient of friction (COF) and its evolution is calculated during the solution by using a subroutine in Abaqus. The model is validated by strain gauge measurements in a running engine. The resulted friction coefficient distribution matches well with the findings from a laboratory engine. The described methodology increases the accuracy of the fretting damage prediction by using a more realistic friction coefficient definition.

The high and very high cycle fatigue (VHCF) properties of ultrahigh-strength Ck45M steel processed by thermomechanical rolling integrated direct quenching were investigated. S-N tests with smooth and small drilled holes containing specimens as well as near-threshold fatigue crack growth measurements were performed up to 2 Â 10 10 cycles using ultrasonic-fatigue testing technique. The fatigue strength of smooth specimens is mainly determined by the size of nonmetallic inclusions. For surface defects larger than 80 μm, the fatigue limit can be correlated with a constant threshold-stress intensity factor. The ffiffiffiffiffiffiffiffiffi area p -parameter model adequately predicts the fatigue limit for internal defects and for surface defects with sizes between 30 and 80 μm. VHCF failures from smaller surface defects occur at stress amplitudes below the predicted fatigue limit. The long-crack threshold in ambient air is close to the effective threshold stress intensity factor. In optically dark areas at interior inclusions, cracks grow at mean propagation rates of 10 À15 m/cycles.

Summary. We discuss a methodology for systematically using an Simulation Process and Data Management (SPDM) platform in product development. The purpose of this paper is to get the reader acquianted with the concept and the importance of such an approach. The target is to base product development on clearly defined targets and requirements in different phases of the product development lifecycle. This is achieved by means of a data-centered approach where all data is retained in a digital form in the platform. Instead of reporting, users are provided with different views to the same data. We will discuss how a static document-based validation system can be replaced by a common validation data platform. In addition, we aim to base the validation requirements on a reliability analysis workflow.In this case, the platform is used not only to handle the simulation data but to encompass the whole product validation scope. To this end, the fundamental concept of our data management approach is to couple the requirements directly to the simulations and handle all the design decision data together with the simulations using these to drive the design.The motivation for the activity is a dramatic reduction in product development time based on a possibly longer concept phase but less iterations during the detail design phase. Future developments will include moving also the physical testing data and coupling that with the corresponding simulations and validation requirements.

Summary. On combustion engine a connecting rod converts the reciprocating motion of a piston to the rotating motion of a crankshaft. Simulation of a large bore connection rod has been performed in Abaqus Standard, using boundary conditions from AVL EXCITE Power Unit. By using the latest simulation technologies and the well known boundary conditions, simulated stresses correspond very well with the measured ones from a running engine.

Summary. The finite element simulation of a cylinder head has been carried out with Abaqus Standard using Z-mat material model, with thermal boundary conditions coming from combined conjugate heat transfer and gas-exchange simulations. The fatigue post-processing of results has been done with Z-post software using ONERA fatigue model. The resulting lifetime values have been found out to correspond well to observations from the field.

Summary.A Bayesian sequential experimental design for fatigue testing based on D-optimality and a non-linear continuous damage model was implemented. The model has two asymptotes for the number of cycles to failure: the fatigue limit and the ultimate tensile strength. With the introduction and stochastic handling of these asymptotes, the D-optimal design accounts naturally for the whole range of reasonable testing levels. Sequential design ensures that all the available data is used efficiently while choosing the next test level.