Breakout Session

Altair | Ming Zhou
Future of Design, Simulation and Optimization

Traditionally product design starts with CAD, typically inheriting design concepts largely from previous product generations. Topology optimization inverts the process by driving design concept creation through simulation. This puts CAE in front of CAD in the product development life cycle, transforming the design process from evolution to innovation. Remarkable results have been achieved on many iconic products, including the Boeing 787, Airbus 380, and 350, that everyone of us have touched firsthand. As we reflect up on recent technology advancements, let’s take a longer view into the future and imagine what a engineer’s day may look like in 20, 50 and 100 years.

Show more

Comer Industries S.p.A. | Elisabetta Fava
Oil flow rate optimization of an axle with an integrated input planetary stage for an uphill and downhill path

An axle with an integrated input planetary stage has been simulated with ParticleWorks to predict the oil flow path in the planetary stage when the machine in which it is mounted faces the changes of slope of the ground. For this reason, a speed law that reproduces the slope variations has been imposed: a first step in which the axle is in an horizontal configuration is followed by the second step in which it is sloped to simulate the uphill configuration, then the downhill condition is the third step followed again by the horizontal position.
The first simulation has been run considering the current housing oil passages geometry and the current level of oil and it has shown that almost all the quantity of oil that arrives in the oil passages reaches the two bearings of the spiral pinion shaft and does not arrive to the planetary stage during the sloped conditions. Thus, a second simulation has been run modifying the oil passages geometry, maintaining the previous oil level: in this case there is a significant increase of oil quantity that reaches the planetary stage and also during the sloped configurations meaning that the optimizations are working properly. In the third and last simulation the oil level has been increased: this simulation has shown that there is a further increase of oil exchange between the oil passages and the planetary stage but the oil quantity that remains in the planetary stage doesn’t change significantly.
With those three simulations it has been possible to improve the lubrication of the planetary stage optimizing only the housing oil passages geometry without increasing the oil level that would have meant increase of temperature and loss of efficiency.

Show more

Drivetrain components are required to withstand large numbers of cycles and various dynamic loading events. Accurate analysis of driveline components can be achieved by considering the dynamics in the system as well as the component structural characteristics. An example is the simulation of the flexible boot of a constant velocity (CV) joint assembly that is used in an off-highway application with extreme transmission angles. The use of multibody dynamics and nonlinear finite element analysis techniques are used to simulate the boot behavior. The simulation technique includes a replication of the assembly process as well as the dynamic operation. Validation of this simulation consists of excellent correlation between simulation and test for the collapse of two outer folds of the boot (forming dimples), the shape of the boot, and the contact between folds, all when rotating with a large transmission angle. Process automation was used to increase the efficiency of such simulations.

Show more

Engineering Center Steyr | Gerhard Spindelberger
Improving the lightweight design of an e-drive system by means of fatigue analysis

Innovative lightweight design is the key to reducing consumption and pollutant emissions. Especially the paradigm shift currently underway towards more electrification demands new possibilities for saving weight to be explored. Thus the aim of this presentation is to show how a fatigue life analysis can be carried out for a modern electric drive system. The e-drive system will be subjected to an engine run-up simulation with excitation data coming from gear simulation. Since vibration phenomena play an essential role here, a modal fatigue analysis is carried out. The workflow consists of three steps. First an eigenfrequency and modal response analysis are carried out to characterize the dynamic behavior of the structure. Next the FEMFAT add-on tool HARMONIC is used for the data preparation of the modal participation factors for fatigue analysis. The subsequent modal fatigue analysis in FEMFAT is based on the principle of linear superposition of modal stresses and modal participation factors. In this way endurance safety factors are computed.

Show more

In the recent years, the usage of HS-steels has risen significantly in the automotive field. Their characteristics, such as hardness and favorable weight to strength ratio, can increase safety, fuel efficiency and overall product profitability. On the other hand, the dual phase steels, which being more ductile can be used in many more parts of the body in white. They offer a wide range of characteristics in terms of ultimate strength and elongation, according to the volume fraction of the martensitic and ferritic phases.
In this context, for the design with these materials it has become crucial to be able to characterize them precisely and accurately predict their failure in many complex conditions, to fully exploit their capabilities and describe accurately the vehicle response in a crash scenario. LS-DYNA, for these kinds of simulations, is one of the most accredited simulation software. The authors aim to provide the crash analysts a verified workflow to prepare material cards for LS-DYNA.
In this work, the experimental evaluation of the materials was carried out using the digital image correlation (DIC). With such technology, the displacement fields of the test specimens is recorded. The evaluated field was processed as a family of stress-strain curves (hyper-curves) and became the objective of the optimization. This approach is named full field approach and was performed using the optimization software LS-OPT that since version 6.0 presents the capability to analize hyper-curves.
To evaluate the effectiveness of the full field approach a parallel study was implemented. The same routine of optimization run with a single stress-strain curve, which was measured with an extensometer. The comparison between the results obtained with the traditional approach and the results obtained with the full field approach highlighted the strenghts and the limitations of the two methods.

Industrie Saleri Italo S.p.A. | Remo De Donno
Design of centrifugal pumps by CFD-based optimization techniques

This study investigates the capability of a surrogate-based optimization technique for the design of centrigufal pumps for the automotive field.
A fully three-dimensional geometry parametrization based on Bézier surfaces for the impeller, vaneless diffuser and the volute is presented. The link between pump geometry and pump performance is given by CFD simulations performed with ANSYS CFX, while the optimization strategy is managed by the Dakota software.
The results of this work show an effective methodology for the new design of centrifugal pumps at the best efficiency point.

Show more

Istituto Italiano di Tecnologia | Francesco Madaro
Flexible Aluminum Nitride-based Energy Harvester by Vortex induced vibration for Powering Remote Gas Sensor in Car's Exhaust: model and experimental validation

Flexible piezoelectric materials offer an efficient route to harvest energy from the fluid environments to power remote sensor and electronics. Specifically, the aim of the present work is to describe electrical power generation by energy harvesting from vortex induced vibrations from the fluid flow of the exhaust gas of a Diesel car by a flexible Aluminum Nitride-based device. The harvested electrical energy will power a remote gas sensor and a transmitter in order to build an Internet of Things (IoT) node. To optimize the design of the piezoelectric harvester, a computer fluid dynamics (CDF) and a piezoelectric structure interaction (PSI) model of the fluid flow environment and of the harvester was constructed using ANSYS. The simulations of electrical power generated were compared with the experimental measurements carried on the real harvester, fabricated using the same geometrical and physical parameters used in the computer aided model. Although some discrepancies between the two scenarios, real measurements and simulations, were observed, the present work shows a milestone towards building a solid ANSYS model of the energy harvester and use it to optimize the design.

Show more