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Further improvements of internal combustion engines to reduce fuel consumption and to face future legislation constraints are strictly related to the study of mixture formation. The reason for that is the desire to supply the engine with homogeneous charge, towards the direction of a global stoichiometric blend in the combustion chamber. Fuel evaporation and thus mixture quality mostly depend on injector atomization features and charge motion within the cylinder. 3D-CFD simulations offer great potential to study not only injector atomization quality but also the evaporation behavior. Nevertheless coupling optical measurements and simulations for injector analysis is an open discussion because of the large number of influencing parameters and interactions affecting the fuel injection’s reproducibility. For this purpose, detailed numerical investigations are used to describe the injection phenomena.

The industry is working intensively on the precision of thermal management. By using complex thermal management strategies, it is possible to make engine heat distribution more accurate and dynamic, thereby increasing efficiency. Significant efforts are made to improve the cooling efficiency of the engine water jacket by using 3D CFD. As well, 1D simulation plays a significant role in the design and analysis of the cooling system, especially for considering transient behaviour of the engine. In this work, a practice-oriented universal method for creating a 1D water jacket model is presented. The focus is on the discretization strategy of 3D geometry and the calculation of heat transfer using Nusselt correlations. The basis and reference are 3D CFD simulations of the water jacket. Guidelines for the water jacket discretization are proposed. The heat transfer calculation in the 1D-templates is based on Nusselt-correlations (Nu = Nu(Re, Pr)), which are derived from 3D CFD simulations.

As a consequence of reduced fuel consumption, direct injection gasoline engines have already prevailed against port fuel injection. However, in-cylinder fuel homogenization strongly depends on charge motion and injection strategies and can be challenging due to the reduced available time for mixture formation. An insufficient homogenization has generally a negative impact on the combustion and therefore also on efficiency and emissions. In order to reach the targets of the intensified CO2 emission reduction, further increase in efficiency of SI engines is essential. In this connection, 0D/1D simulation is a fundamental tool due to its application area in an early stage of development and its relatively low computational costs. Certainly, inhomogeneities are still not considered in quasi dimensional combustion models because the prediction of mixture formation is not included in the state of the art 0D/1D simulation.

The Institute for Polymer Testing and Polymer Science of the University of Stuttgart has been investigating automotive parts, structures and cars during their life cycle in plenty cooperation with the European automobile producers and their suppliers for the last 9 years. Therefore a holistic approach has been developed to combine tasks from technique, economic and environment in a methodology called Life Cycle Engineering (LCE). The goal is to find a way to support designer and engineers as well as police makers and public with this three-dimensional interrelated information to have the possibility to manufacture future products in a more sustainable way without loosing contact two the traditional parameters technique and costs.

The EU SPARC Project (Secure Propelled Vehicle with Advanced Redundant Control) has developed a new system architecture that enables effective application of driver assisted systems in an X-by-wire powertrain. A major challenge in the conception of such a system is development of a reliable electrical energy supply. A simulation is the most important tool for enabling the fundamental aspects to work, as for example, a dimensioning of the powernet. This article explains our approach in this SPARC simulation. We provide suggestions through examples of how to find simulation solutions for powernet dimensioning, as well as for the conception and validation of energy management strategies.

During sheet metal forming processes, the friction conditions have a decisive influence on forming limits, the robustness of the production process and the quality of the parts produced, with significant forces required to overcome friction between the sheet and the tools. If lot-to-lot reproducibility is to be guaranteed, an appropriate method of characterizing the sheet surface topography is needed to monitor the sheet metal fabrication process. Newly developed optical measurement techniques and computer workstation technology are presented which enable the topography of sheet surfaces to be described in three dimensions.

Knocking is one of today’s main limitations in the ongoing efforts to increase efficiency and reduce emissions of spark-ignition engines. Especially for synthetic fuels or any alternative fuel type in general with a much steeper increase of the knock frequency at the KLSA, such as hydrogen, precise knock prediction is crucial to exploit their full potential. This paper therefore proposes a post-processing tool enabling further investigations to continuously gain better understanding of the knocking phenomenon. In this context, evaluation of local auto-ignitions preceding knock is crucial to improve knowledge about the stochastic occurrence of knock but also identify critical engine design to further optimize the geometry. In contrast to 0D simulations, 3D CFD simulations provide the possibility to investigate local parameters in the cylinder during the combustion.

Urban air mobility (UAM) is a fast-growing industry that utilizes electric vertical take-off and landing (eVTOL) technologies to operate in densely populated urban areas with limited space. However, atmospheric icing serves as a limitation to its operational envelope as in-flight icing can happen all year round anywhere around the globe. Since icing in smaller aviation systems is still an emerging topic, there is a necessity to study icing of eVTOL rotors specifically. Two rotor geometries were chosen for this study. A small 15-inch rotor was selected to illustrate a multirotor UAV drone, while a large 80-inch rotor was chosen to represent a UAM passenger aircraft. The ice accretion experiments were conducted in an icing wind tunnel on the small 15-inch rotor. The icing simulations were performed using FENSAP-ICE. The ice accretion simulations of the 15-inch rotor sections at –5 °C show a large, rather streamlined ice shape instead of the expected glaze ice characteristics.

In this paper, the differences between a production car of the 2018 A-class and an early stage vehicle model with a mostly similar outer skin are examined experimentally and numerically. The aerodynamic development of vehicles at Mercedes-Benz is divided into several phases. When comparing force coefficients differences can be observed between these distinct hardware stages as well as when comparing steady state simulations to wind tunnel measurements. In early phases when prototype vehicles are not yet available, so-called aero foam models are used. These are well-defined full-sized vehicle models, as the outer skin is milled from Polyurethane. Important aerodynamic characteristics such as a motor compartment with a cooling module, deflecting axles with rotatable wheels and underbody covers are represented.

Life cycle assessment offers a suitable methodology to evaluate environmental impacts over the total life cycle of the car. Indeed the effort for LCA studies of complex products like cars is very high. Design for environment tools can help to reduce the effort for environmental evaluation because of their direct integration in the designers workflow. As DFE is not standardized, it should be based on the reliable data from LCA. A connection between LCA and DFE offers the possibility to integrate environmental evaluation with tolerable effort directly in the design process while keeping the transparency and reliability of LCA.

In this paper the effects of pulsating blankholder forces in deep draw processes for sheet metal parts are discussed. Areas with and without tangential compressive stresses in the flanges, which are located between the binders, are discussed separately. Areas without tangential compressive stresses can be simulated by a special friction strip-draw test using a pulsating normal force ( representing the blankholder force ). Investigations using this equipment show that by pulsating blankholder forces it is possible to avoid galling and to reduce the friction force. Areas with tangential compressive stresses can be simulated by deep drawing axissymmetric cups using a pulsating blankholder force. Investigations with this equipment show that without increasing the danger of wrinkling the friction forces can be reduced by pulsating blankholder forces, when a certain frequency limit is reached.

Multi-dimensional modelling of the flow and combustion promises to become a useful optimisation tool for IC engine design. Currently, the total simulation time for an engine cycle is measured in weeks to months, thus preventing the routine use of CFD in the design process. Here, we shall describe three tools aimed at reducing the simulation time to less than a week. The rapid template-based mesher produces the computational mesh within 1-2 days. The parallel flow solver STAR-CD performs the flow simulation on a similar time-scale. The package is completed with COVISEMP, a parallel post-processor which allows real-time interaction with the data.

Engine valve flow coefficients are used to describe the flow throughput performance of engine valve/port designs, and to model gas exchange in 0D/1D engine simulation. Valve flow coefficients are normally determined at a stationary flow test bench, separately for intake and exhaust side, in the absence of the piston. However, engine operation differs from this setup; i. a. the piston might interact with valve flow around scavenging top dead center, and instead of steady boundary conditions, valve flow is nearly always subjected to pressure pulsations, due to pressure wave reflections within the gas exchange ports. In this work the influences of piston position and flow pulsation on valve flow coefficients are investigated for different SI engine geometries by means of 3D CFD and measurements at an enhanced flow test bench.

Engine valve flow coefficients are not only used to characterize the performance of valve/port designs, but also for modelling gas exchange in 0D/1D engine simulation. Flow coefficients are usually estimated with small pressure ratios and at ambient air conditions. In contrast, the ranges for pressure ratio, pressure and temperature level during engine operation are much more extensive. In this work the influences of these three parameters on SI engine poppet valve flow coefficients are investigated using 3D CFD and measurements for validation. While former investigations already showed some pressure ratio dependencies by measurement, here the use of 3D CFD allows a more comprehensive analysis and a deeper understanding of the relevant effects. At first, typical ranges for the three mentioned parameters during engine operation are presented.