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Hydrodynamic radial journal bearings under unsteady load, which are common for automotive applications, are exposed to cavitation, e.g. flow, suction, shock and exit cavitation. The fluid mechanic description of the flow in journal bearings takes advantage of the small bearing clearance, which allows the reduction of the Navier-Stokes equations and leads to the Reynolds equation. The Reynolds equation is two-dimensional, the radial pressure gradient and the radial velocity component are neglected. However, the equation includes the surface velocities, oil density and viscosity and describes the relation between hydrodynamic pressure and local clearance. With the introduction of a cavitation index or a mass flow coefficient a powerful method to carry out numerical studies can be created, which allows the calculation of flow properties and the prediction of regions where the lubrication film disintegrates.

The introduction of real driving emissions cycles and increasingly restrictive emissions regulations force the automotive industry to develop new and more efficient solutions for emission reductions. In particular, the cold start and catalyst heating conditions are crucial for modern cars because is when most of the emissions are produced. One interesting strategy to reduce the time required for catalyst heating is post-oxidation. It consists in operating the engine with a rich in-cylinder mixture and completing the oxidation of fuel inside the exhaust manifold. The result is an increase in temperature and enthalpy of the gases in the exhaust, therefore heating the three-way-catalyst. The following investigation focuses on the implementation of post-oxidation by means of scavenging in a four-cylinder, turbocharged, direct injection spark ignition engine. The investigation is based on detailed measurements that are carried out at the test-bench.

The continuous pursuit of higher combustion efficiencies, as well as the possible usage of synthetic fuels with different properties than fossil-ones, require reliable and low-cost numerical approaches to support and speed-up engines industrial design. In this context, SI engines operated with homogeneous ultra-lean mixtures both characterized by a classical ignition configuration or equipped with an active prechamber represent the most promising solutions. In this work, for the classical ignition arrangement, a 3DCFD strategy to model the impact of the ignition system type on the CCV is developed using the RANS approach for turbulence modelling. The spark-discharge is modelled through a set of Lagrangian particles, whose velocity is modified with a zero-divergence perturbation at each discharge event, then evolved according to the Simplified Langevin Model (SLM) to simulate stochastic interactions with the surrounding gas flow.

An improved version of the ECFM-3Z combustion model coupled with advanced models for NO and soot formation has been implemented in the CFD code FIRE and validated with respect to its applicability to conventional and alternative Diesel combustion. For this purpose the set of models was applied to the calculation of combustion and pollutant formation in a high-speed DI Diesel engine for selected operating points adopting a large number of DoE based combustion system parameter variations. Assessment of the models' performance was enabled via comparison of the calculation results with the corresponding experimental data. Good agreement of calculated and measured in-cylinder pressure traces as well as pollutant formation trends could be observed for both the conventional and alternative Diesel combustion modes for the investigated parameter variations.

Renewable fuels, such as bio- and e-fuels, are of great interest for the defossilization of the transport sector. Among these fuels, methanol represents a promising candidate for emission reduction and efficiency increase due to its very high knock resistance and its production pathway as e-fuel. In general, reliable simulation tools are mandatory for evaluating a specific fuel potential and optimizing combustion systems. In this work, a previously presented methodology (Esposito et al., Energies, 2020) has been refined and applied to a different engine and different fuels. Experimental data measured with a single cylinder engine (SCE) are used to validate RANS 3D-CFD simulations of gaseous engine-out emissions. The RANS 3D-CFD model has been used for operation with a toluene reference fuel (TRF) gasoline surrogate and methanol. Varying operating conditions with exhaust gas recirculation (EGR) and air dilution are considered for the two fuels.

A chemical sub-model for realistic CFD simulations of Diesel engines is developed and demonstrated by application to some test cases. The model uses a newly developed progress variable approach to incorporate a realistic treatment of chemical reactions into the description of the reactive flow. The progress variable model is based on defining variables that represent the onset and temporal development of chemical reactions before and during self ignition, as well as the stage of the actual combustion. Fundamental aspects of the model, especially its physical motivation and finding a proper progress variable, are discussed, as well as issues of practical implementation. Sample calculations of Diesel-typical combustion scenarios are presented which are based on the progress-variable model, showing the capability of the model to realistically describe the ignition-and combustion phase.

In the last years motorsport is facing a technical revolution concerning the engine technology in every category, from touring car championships up to the F1. The strategy of the car manufacturers to bring motorsport engine technology closer to mass production one (e.g. turbo-charging, downsizing and direct injection) allows both to reduce development costs and to create a better image and technology transfer by linking motorsport activities to the daily business. Under these requirements the so-called Global Race Engine (GRE) concept has been introduced, giving the possibility to use one unique engine platform concept as basis for different engine specifications and racing categories. In order to optimize the performance of this kind of engines, especially due to the highly complex mixture formation mechanisms related to the direct injection, it is nowadays mandatory to resort to reliable 3D-CFD simulations.

Due to the accidents of the motor vehicles and the osteoporosis, many people enface a lot of troubles and sometimes necessities for replacement of their knee joints. Practically, mechanical properties and surface characteristics of Total Knee Replacement (TKR) are very important parameters for improving the performance response in human. The meniscus is a small element and an essential part of the TKR. The knee meniscus has special feature allows the easy dynamic loading and motion of leg and foot with high accuracy and good balance. Therefore design and analysis of the geometrical shape for the meniscus replacement is worthy to be studied. In this paper, a proposed design using a computer software package has been presented. 3D simulation analyses of a variety of meniscus thickness and different materials under different loads are investigated. The compression stresses and surfaces deformations are determined numerically through the Finite Element Analysis (FEA) technique.

The combination of multi purpose software with powertrain specific application codes allows highly flexible simulation models, which are independent on the specific engine concept. Related to the requests those models may be refined or simplified during the simulation process. Finally a fully coupled 3D dynamic simulation including flexible components is performed to assess the engine crankshaft's durability. To take into account the stiffness of the cranktrain components and the cylinder block at first a linear Finite Element Analysis (FEA) simulation is performed. Via modal reduction the complete deformation order information of the FEA simulation are reduced to the necessary information for the dynamic Multi Body System (MBS) simulation [1, 2]. All main boundary conditions of the system, e. g. gas forces, oil temperature or driveline application are taken into account.

In CFD (Computational Fluid Dynamics) verification of vehicle aerodynamics, detailed velocity measurements are required. The conventional 2D-PIV (Two Dimensional Particle Image Velocimetry) needs at least twice the number of operations to measure the three components of velocity ( u,v,w ), thus it is difficult to set up precise measurement positions. Furthermore, there are some areas where measurements are rendered impossible due to the relative position of the object and the optical system. That is why the acquisition of detailed velocity data around a vehicle has not yet been attained. In this study, a detailed velocity measurement was conducted using a 3D-PIV measurement system. The measurement target was a quarter scale SAE standard vehicle model. The wind tunnel system which was also designed for a quarter scale car model was utilized. It consisted of a moving belt and a boundary suction system.

The presented work describes how numerical modeling techniques were extended to simulate a full Selective Catalytic Reduction (SCR) NOx aftertreatement system. Besides predicting ammonia-to-NOX ratio (ANR) and uniformity index (UI) at the SCR inlet, the developed numerical model was able to predict NOx reduction and ammonia slip. To reduce the calculation time due to the complexity of the chemical process and flow field within the SCR, a semi-1D approach was developed and applied to model the SCR catalyst, which was subsequently coupled with a 3D model of the rest of the exhaust system. Droplet depletion of urea water solution (UWS) was modeled by vaporization and thermolysis techniques while ammonia generation was modeled by the thermolysis and hydrolysis method. Test data of two different SCR systems were used to calibrate the simulation results. Results obtained using the thermolysis method showed better agreement with test data compared to the vaporization method.

A progress variable approach for the 3D-CFD simulation of DI-Diesel combustion is introduced. Considering the Diesel-typical combustion phases of auto-ignition, premixed and diffusion combustion, for each phase, a limited number of characteristic progress variables is defined. By spatial-temporal balancing of these progress variables, the combustion process is described. Embarking on this concept, it is possible to simulate the reaction processes with detailed chemistry schemes. The combustion model is coupled with a mesh-independent Eulerian-spray model in combination with orifice resolving meshes. The comparison between experiment and simulation for various Diesel engines shows good agreement for pressure traces, heat releases and flame structures.

In the context of the energy transition, CO2-neutral solutions are of enormous importance for all sectors, but especially for the mobility sector. Hydrogen as an energy carrier has therefore been the focus of research and development for some time. However, the development of hydrogen combustion engines is in many respects still in the conception phase. Automotive system providers and engineering companies in the field of software development and simulation are showing great interest in the topic. In a joint project with the industrial partners Robert Bosch GmbH and AVL Germany, combustion in a H2-DI-engine for use in light-duty vehicles was methodically investigated using the CFD tool AVL FIRE®. The collaboration between Robert Bosch GmbH and the Institute for Mobile Systems (IMS) at Otto von Guericke University Magdeburg has produced a model study in which model approaches for the combustion of hydrogen can be analyzed.

The dynamic model is built in Siemens Simcenter Amesim platform and simulates the performances on track of JUNO, a low energy demanding Urban Concept vehicle to take part in the Shell Eco-Marathon competition, in which the goal is to achieve the lowest fuel consumption in covering some laps of a racetrack, with limitations on the maximum race time. The model starts with the longitudinal dynamics, analysing all the factors that characterize the vehicle’s forward resistance, like aerodynamic forces, altimetry changes and rolling resistance. To improve the correlation between simulation and track performances, the model has been updated with the implementation of a Single-Track Model, including vehicle rotation around its roll axis, and a 3D representation of the racetrack, with an automatic trajectory following control implemented. This is crucial to characterise the vehicle’s lateral dynamics, which cannot be neglected in simulating its performances on track.

3M is committed to continuously improving products and their manufacture toward the goal of sustainability. The 3M Life Cycle Management (LCM) program has been established to implement this goal. It utilizes a matrix tool to facilitate the review. The matrix consists of LCM Stage (Material Acquisition, R&D Operations, Manufacturing Operations, and Customer Use/Disposal) and Impact (Environment, Health, Safety, and Energy/Resources). The program is coordinated at the staff level by the Corporate Product Responsibility group. The corporate goal is to apply LCM to all new and existing products. The LCM program started with evaluations of new products within business units. Since 3M produces more than 60,000 products manufactured from more than 10,000 different raw materials, the routine evaluation of individual products challenges available staff and business unit resources. A technology-based approach for doing LCMs has been implemented to meet the challenge.

The process of translating customer needs into successful commercialized products and services has been the subject of many books, articles and papers [1, 2, 3, 4, 5, 6]. This process has many facets and nuances depending on the type of product or service being developed. Factors impacting this translation include the target audience, cost, timing and return on investment. While some of these factors may be more important than others for any given project, there are six core elements that are present in every successful new product commercialization venture: Commercialization Components: Customer Understanding Technology Understanding Customer Feedback Market Awareness People and Process: Skilled Project Management Commercialization Process In this paper we will define and describe these core elements and some of the important building blocks, tools and tactics. We will illustrate with real-world examples how these elements are used and measured.

This paper aims at providing the scientific community with an overview of the H2020 European project 3beLiEVe and of its early achievements. The project has the objective of delivering the next generation Lithium-Nickel-Manganese-Oxide (LNMO) battery cells, in line with the target performance of the “generation 3b” Li-ion battery technology, as per EU SET-plan Action 7. Its activities are organized in three main pillars: (i) developing the 3b next generation LMNO battery cell, equipped with (ii) an array of internal and external sensors and complemented by (iii) manufacturing and recycling processes at scale. At present, 3beLiEVe is approaching the completion of its first project year (out of a total project planned duration of 42 months). Hence this paper, beyond presenting the overall project’s structure and objectives, focuses on its earliest results in the fields of the cell material formulation, arrangement of sensors and design of the battery pack.

The present article is concerned with the investigation of the engine noise induced by the piston slap of an actual passenger car Diesel engine. The focus is put on the coherence of piston secondary movement, impact of the piston on the cylinder liner, generated structure-borne noise excitation of the engine structure and the occurring acceleration on the engine surface. Additionally, the influence of a varying piston-pin offset and piston clearance is evaluated. The analyses are conducted using an elastohydrodynamic multi-body simulation model, taking into account geometry, stiffness and mass information of the single components as well as considering elastic and hydrodynamic behavior of the piston-liner contact. A detailed description of the simulation model will be introduced in the article. The obtained results illustrate the piston secondary motion and the related structure-borne noise on the engine surface for several piston-pin offsets and piston clearances.

Developing lightweight, stiff and crash-resistant vehicle body structures requires a balance between part geometry and material properties. High strength materials suitable for crash resistance impose geometry limitations on depth of draw, radii and wall angles that reduce geometric efficiency. The introduction of 3rd generation Advanced High Strength Steels (AHSS) can potentially change the relationship between strength and geometry and enable simultaneous improvements in both. This paper will demonstrate applicability of 3rd generation AHSS with higher strength and ductility to replace the 780 MPa Dual Phase steel in a sill reinforcement on the current Jeep Cherokee. The focus will be on formability, beginning with virtual simulation and continuing through a demonstration run on the current production stamping tools and press.

Based on the success of the second-generation Genesis G80 model, Hyundai Motor has declared the independence of Genesis as a luxury car brand in 2015. The third-generation G80 is the representative model of the Genesis brand and has a unique identity of Genesis that can surpass its competitors. In addition, it was necessary to develop seats that were considered not only for ICE but also for the scalability of electric vehicles. A newly formed Genesis organization established the Genesis design philosophy of its own. Four key elements of the design philosophy were comfort, aesthetics, usability and safety. The third-generation Genesis seats incorporate its design philosophy of seat design and new technologies based on comfort, aesthetics, usability, and safety. This paper describes the seat development of the Ergo Motion seat, Rear Seat Relaxtion(Relax + Position), Seat Syling, AVN switch display and PSS(pre-active safety seat )system, which are representative technologies.