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Battery electric vehicles (BEVs) are equipped with Mobile Air Conditioning systems (MACs) to ensure a comfortable cabin temperature in all climates and ambient conditions as well as the optional conditioning of the traction battery. An assessment of the global electrical energy consumption of various MACs has been derived, where the basis of the assessment procedure is the climate data GREEN-MAC-LCCP 2007 (Global Refrigerants Energy & Environmental - Mobile Air Condition - Life Cycle Climate Performance) and the improved LCCP2013 (Life Cycle Climate Performance. The percentage driving time during 6 AM and 24 PM is divided into six different temperature bins with the solar radiation and relative humidity for 211 cities distributed over Europe, North, Central, and South America, Asia, South West Pacific, and Africa. The energy consumption of the MACs is determined by a thermal vehicle simulation. In this work, four different MACs are simulated and compared.

After the success of the 4-cylinder 1.9-liter TDI and SDI direct-injection diesel engines in the Passat, Jetta and Polo classes, a new 3-cylinder TDI has been developed for use in the "Lupo 3L,' a compact car with a fuel consumption of 3 liters per 100 km. A new injection system with unit injectors, together with a fully electronically controlled engine management system featuring drive-by-wire- technology, a turbocharger with variable turbine geometry and a fully automated mechanical gearbox and clutch, for the first time ensures the potential to meet the stringent D4 exhaust emissions level and to achieve excellent fuel economy. The wheel-torque based engine and gearbox management systems optimize engine operation in terms of efficiency and emissions.

Wet-running multi-plate clutches and brakes are important components of modern powershift gearboxes and industrial powertrains. In the open stage, drag losses occur due to fluid shear. The identification of drag losses is possible by experiment or CFD-simulation. For the calculation of the complex fluid flow of an open clutch, CFD-approaches such as the volume of fluid (vof) method or the Singhal cavitation model are applicable. Every method has its own specific characteristics. This contribution sets up CFD-calculation models for different clutches with diverse groove designs. We present results of calculations in various operating conditions obtained from the Singhal cavitation model and the vof method. The usage of modern commercial CFD-Tools (Simerics MP+) results in short calculation times.

The reduction of both harmful emissions (CO, HC, NOx, etc.) and gases responsible for greenhouse effects (especially CO2) are mandatory aspects to be considered in the development process of any kind of propulsion concept. Focusing on ICEs, the main development topics are today not only the reduction of harmful emissions, increase of thermodynamic efficiency, etc. but also the decarbonization of fuels which offers the highest potential for the reduction of CO2 emissions. Accordingly, the development of future ICEs will be closely linked to the development of CO2 neutral fuels (e.g. biofuels and e-fuels) as they will be part of a common development process. This implies an increase in development complexity, which needs the support of engine simulations. In this work, the virtual modeling of real fuel behavior is addressed to improve current simulation capabilities in studying how a specific composition can affect the engine performance.

A reliable environment perception is a requirement for safe automated driving. For evaluating and demonstrating the reliability of the vehicle’s environment perception, field tests offer testing conditions that come closest to the vehicle’s driving environment. However, establishing a reference ground truth in field tests is time-consuming. This motivates the development of a procedure for learning the vehicle’s perception reliability from fleet data without the need for a ground truth, which would allow learning the perception reliability from fleet data. In Berk et al. (2019), a method based on Bayesian inference to determine the perception reliability of individual sensors without the need for a ground truth was proposed. The model utilizes the redundancy of sensors to learn the sensor’s perception reliability. The method was tested with simulated data.

This paper summarizes the validation of prototype vehicle-to-infrastructure (V2I) safety applications based on Dedicated Short Range Communications (DSRC) in the United States under a cooperative agreement between the Crash Avoidance Metrics Partners LLC (CAMP) and the Federal Highway Administration (FHWA). After consideration of a number of V2I safety applications, Red Light Violation Warning (RLVW), Curve Speed Warning (CSW) and Reduced Speed Zone Warning with Lane Closure Warning (RSZW/LC) were developed, validated and demonstrated using seven different vehicles (six passenger vehicles and one Class 8 truck) leveraging DSRC-based messages from a Road Side Unit (RSU). The developed V2I safety applications were validated for more than 20 distinct scenarios and over 100 test runs using both light- and heavy-duty vehicles over a period of seven months. Subsequently, additional on-road testing of CSW on public roads and RSZW/LC in live work zones were conducted in Southeast Michigan.

In this paper the emissions of regulated and unregulated exhaust gas components of a fleet of diesel passenger cars measured at Volkswagen in the eighties are compared with the results of a new investigation on modern direct-injection diesel vehicles. The potential of improved diesel fuels to reduce emissions is also examined. The emissions of regulated exhaust gas components as well as fuel consumption have been reduced significantly in the last years as a result of the systematic further development of conventional swirl chamber engines and exhaust gas after-treatment as well as the introduction of SDI/TDI engines. As was to be expected, this has also had a positive effect on the emissions of unregulated exhaust gas components. It has been possible, for example, to reduce the polycyclic aromatic hydrocarbons adsorbed on diesel particulates by more than 95%.

Electrified vehicles are particularly quiet, especially at low speeds due to the absence of combustion noises. This is why there are laws worldwide for artificial driving sounds to warn pedestrians. These sounds are generated using a so-called Acoustic Vehicle Alerting System (AVAS) which must maintain certain minimum sound pressure levels in specific frequency ranges at low speeds. The creation of the sound currently involves an iterative and sometimes time-consuming process that combines composing the sound on a computer with measuring the levels with a car on an outside noise test track. This continues until both the legal requirements and the subjective demands of vehicle manufacturers are met. To optimize this process and reduce the measurement effort on the outside noise test track, the goal is to replace the measurement with a simulation for a significant portion of the development.

The VOLKSWAGEN VANAGON SYNCRO is presented as a novel 4 WD. The visco coupling is the heart of the forward drive train. Main advantages are automatic performance distribution between the axles and self-locking at extreme revolution differences between front and rear. Another important advantage of the standard 2 WD Vanagon is the well-known excellent spring suspension and damping comfort which is not negatively effected by the 4 WD technique. The vehicle is equipped with a new more powerful engine with 2,1 liter displacement and 70 kW (95 HP) nominal power output which is based on the watercooled horizontally opposed engine program. Electronic fuel injection and ignition are integrated into a unique Volkswagen system called DIGIFANTR. Vehicle performance data and fuel economy figures are given in comparison with 2 WD designs and previously available engine power train combinations.

An investigation was conducted to elucidate, how the latest turbocharged, direct injection Volkswagen diesel engine generation with cylinder pressure based closed loop control, to be launched in the US in 2008, reacts to fuel variability. A de-correlated fuels matrix was designed to bracket the range of US market fuel properties, which allowed a clear correlation of individual fuel properties with engine response. The test program consisting of steady state operating points showed that cylinder pressure based closed loop control successfully levels out the influence of fuel ignition quality, showing the effectiveness of this new technology for markets with a wide range of fuel qualities. However, it also showed that within the cetane range tested (39 to 55), despite the constant combustion mid-point, cetane number still has an influence on particulate and gaseous emissions. Volatility and energy density also influence the engine's behavior, but less strongly.

The hatchback of Volkswagen's 3 liter car (3 l fuel consumption per 100 km) consists of an inner component of die casting magnesium (AM50) covered with an aluminum panel from the outside. This hybrid design requires a new manufacturing process: The pre-coated magnesium part will be bonded and folded with the bare aluminum part. Corrosion protection is provided by an organic coating system which both protects against general corrosion and galvanic corrosion. The corrosion of the Al / Mg sandwich has been examined with hybrid samples which are similar to the hatchback. Several powder coatings (epoxy resin, polyester resin, hybrid resin), wet paints and cathodic electro-coating paints of different thicknesses and compositions have been applied to the magnesium part. They show that only powder coating provides adequate protection. Galvanic corrosion at the points of attachment of the hatchback might be possible (for example the bolted joint of the hinge).

The large wind tunnel at the Technische Universität München was upgraded by integrating a modular single-belt system, which enables the simulation of moving ground conditions for ground vehicle testing. Central part of this system is its large belt that moves at a maximum speed of 50 m/s. This belt not only simulates the relative motion between the model vehicle under investigation and the floor, but also drives the model's wheels. Due to its size, the wind tunnel facility is suited for testing 40%-scaled models of typical passenger cars, which are held in place by a newly designed model support system consisting of five struts: One strut to support the body of the model and four struts to hold the model's wheels on top of the moving belt. Another crucial step in upgrading the wind tunnel was to install a boundary layer scoop system to reduce the thickness of the boundary layer approaching the moving belt.

The improvement of vehicle soiling behavior has increasing interest over the past few years not only to satisfy customer requirements and ensure a good visibility of the surrounding traffic but also for autonomous vehicles, for which soiling investigation and improvement are even more important due to the demands of the cleanliness and induced functionality of the corresponding sensors. The main task is the improvement of the soiling behavior, i.e., reduction or even prevention of soiling of specific surfaces, for example, windows, mirrors, and sensors. This is mostly done in late stages of vehicle development and performed by experiments, e.g., wind tunnel tests, which are supplemented by simulation at an early development stage. Among other sources, the foreign soiling on the side mirror and the side window depend on the droplet detaching from the side mirror housing.

Strategic Materials at Reaction Temperatures (SMART) is an approach used to design washcoat systems for passive 4-way emission control catalysts. Light duty diesel vehicles need to meet the European Motor Vehicle Emissions Group (MVEG) cycle or U. S. Federal test procedure (FTP 75). Emissions that are monitored include hydrocarbon (HC), nitrogen oxides (NOx), carbon monoxide (CO) and total particulate matter (TPM). Low engine-exhaust temperatures (< 200°C during city driving) and high temperatures (> 500-800°C under full load and wide-open throttle) make emission control a formidable task for the catalyst designer Gas phase HC, CO and NOx reactions must be balanced with the removal of the soluble organic fraction for the vehicle to be in compliance with regulations. The SMART approach uses model gases under typical operating conditions in the laboratory to better understand the function of individual washcoat components.

To minimize the impact of global warming worldwide, net greenhouse-gas (GHG) emissions have to be reduced. The transportation sector is one main contributor to overall greenhouse gas emissions due to the fact that most of the current propulsion systems rely on fossil fuels. The gasoline engine powertrain is the most used system for passenger vehicles in the EU and worldwide. Besides emitting GHG, gasoline driven cars emit harmful pollutants, which can cause health issues for humans. Hybrid powertrains provide an available short-term solution to reduce fuel consumption and thus overall emissions. Therefore, an overview of the currently available technology and methodology of hybrid cars is provided in this paper as well as an overview of the performance of current HEV cars in real world testing. From the testing, it can be concluded that despite reducing harmful emissions, hybrid vehicles still emit pollutants and GHG when fueled with conventional gasoline.

In a consortium of European industrial partners and research institutes, a combination of industrial development and scientific research was organised. The objective was to improve the catalytic NOx conversion for lean burn cars and heavy-duty trucks, taking into account boundary conditions for the fuel consumption. The project lasted for three years. During this period parallel research was conducted in research areas ranging from basic research based on a theoretical approach to full scale emission system development. NOx storage catalysts became a central part of the project. Catalysts were evaluated with respect to resistance towards sulphur poisoning. It was concluded that very low sulphur fuel is a necessity for efficient use of NOx trap technology. Additionally, attempts were made to develop methods for reactivating poisoned catalysts. Methods for short distance mixing were developed for the addition of reducing agent.

Compatibility has been a passive safety research issue for many years. Great advancements in secondary (passive) safety have been achieved in the last decades through focussing on the self-protection level provided by passenger cars. The next step is to consider the other vehicle involved in the collision as well. Compatibility relates to the simultaneous improvement of both self- and partner- protection. Several tests procedures have been proposed around the world to assess the compatibility of passenger cars. None are considered ready to be implemented. This paper shows that controlling vehicle front-end geometry is the most feasible step to improve both self- and partner-protection. Through this, an increase in the structural interaction potential offered by passenger cars would result. To improve structural interaction, a convergence of front-end structures, to within certain vertical limits, is necessary.

Quantitative 1-D spatially-resolved NO LIF measurements in the combustion chamber of a mass-production SI engine with port-fuel injection using a tunable KrF excimer laser are presented. One of the main advantages of this approach is that KrF laser radiation at 248 nm is only slightly absorbed by the in-cylinder gases during engine combustion and therefore it allows measurements at all crank angles. Multispecies detection turned out to be crucial for this approach since it is possible to calculate the in-cylinder temperature from the detected Rayleigh scattering and the simultaneously acquired pressure traces. Additionally, it allows the monitoring of interfering emissions and spectroscopic effects like fluorescence trapping which turned out to take place. Excitation with 248 nm yields LIF emissions at shorter wavelengths than the laser wavelength (at 237 and 226 nm).

In this study a mixture of dimethyl carbonate (DMC) and methyl formate (MeFo) was used as a synthetic gasoline replacement. These synthetic fuels offer CO2-neutral mobility if the fuels are produced in a closed CO2-cycle and they reduce harmful emissions like particulates and NOX. For base potential investigations, a single-cylinder research engine (SCE) was used. An in-depth analysis of real driving cycles in a series 4-cylinder engine (4CE) confirmed the high potential for emission reduction as well as efficiency benefits. Beside the benefit of lower exhaust emissions, especially NOX and particle number (PN) emissions, some additional potential was observed in the SCE. During a start of injection (SOI) variation it could be detected that a late SOI of DMC/MeFo has less influence on combustion stability and ignitability. With this widened range for the SOI the engine application can be improved for example by catalyst heating or stratified mode.

Over the next decades to come, fossil fuel powered Internal Combustion Engines (ICE) will still constitute the major powertrains for land transport. Therefore, their impact on the global and local pollution and on the use of natural resources should be minimized. To this end, an extensive fundamental and practical study was performed to evaluate the potential benefits of simultaneously co-optimizing the system fuel-and-engine using diesel as an example. It will be clearly shown that the still unused co-optimizing of the system fuel-and-engine (including advanced exhaust after-treatment) as a single entity is a must for enabling cleaner future road transport by cleaner fuels since there are large, still unexploited potentials for improvements in road fuels which will provide major reductions in pollutant emissions both in vehicles already in the field and even more so in future dedicated vehicles.