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Current developments in automotive industry such as hybrid powertrains and the continuously increasing demands on emission control systems, are pushing complexity still further. Validation of such systems lead to a huge amount of test cases and hence extreme testing efforts on the road. At the same time the pressure to reduce costs and minimize development time is creating challenging boundaries on development teams. Therefore, it is of utmost importance to utilize testing and validation prototypes in the most efficient way. It is necessary to apply high levels of instrumentation and collect as much data as possible. And a streamlined data pipeline allows the fleet managers to get new insights from the raw data and control the validation vehicles as well as the development team in the most efficient way. In this paper we will demonstrate a data-driven approach for validation testing.

Trends towards lower vehicle fuel consumption and smaller environmental impact will increase the share of Diesel hybrids and Diesel Range Extended Vehicles (REV). Because of the Diesel engine presence and the ever tightening soot particle emissions, these vehicles will still require soot particle emissions control systems. Ceramic wall-flow monoliths are currently the key players in the Diesel Particulate Filter (DPF) market, offering certain advantages compared to other DPF technologies such as the metal based DPFs. The latter had, in the past, issues with respect to filtration efficiency, available filtration area and, sometimes, their manufacturing cost, the latter factor making them less attractive for most of the conventional Diesel engine powered vehicles. Nevertheless, metal substrate DPFs may find a better position in vehicles like Diesel hybrids and REVs in which high instant power consumption is readily offered enabling electrical filter regeneration.

Automotive embedded systems have become very complex, are strongly integrated, and the safety-criticality and real-time constraints of these systems raise new challenges. The OSEK/VDX standard provides an open-ended architecture for distributed real-time capable units in vehicles. This is supported by the OSEK Implementation Language (OIL), a language aiming at specifying the configuration of these real-time operating systems. The challenge, however, is to ensure consistency of the concept constraints and configurations along the entire product development. The contribution of this paper is to bridge the existing gap between model-driven systems engineering and software engineering for automotive real-time operating systems (RTOS). For this purpose a bidirectional tool bridge has been established based on OSEK OIL exchange format files.

The development process of a combustion engine is now a days strongly influenced by future emission regulations which require further reduction in fuel consumption and precise control of combustion process based on Intake air measurement, during engine development. Intake air flow meters clearly differentiate themselves from typical industrial gas flow meters because of their ability to measure extremely dynamic phenomenon of combustion engine. Thus, high internal data acquisition rate, short response time, ability to measure pulsating and reverse flows with lower measurement uncertainty are the factors that ensures the reliability of the results without being affected by ambient influences, sensor contamination or sensor aging. The AVL developed FLOWSONIX™ is based on ultrasonic transit time measuring principle with broad-band Capacitive Ultrasonic Transducer (CUT) characterized by an excellent air impedance matching strongly distinguishes itself by fulfilling all those requirements.

In order to facilitate the analysis of SI engine combustion phenomena, we have developed a fiber optic system which allows the observation of combustion in essentially standard engines. Optical access to the combustion chamber is achieved with micro-optic elements and optical fibers in the cylinder head gasket. Each fiber views a narrow cone of the combustion chamber and transmits the light seen within this acceptance cone to the detector and recorder unit. A large number of such fiber optic detectors have been incorporated in a cylinder head gasket and this multichannel system was arranged in a geometric configuration which allowed the reconstruction of the spatial flame intensity distribution within the observed combustion chamber cross-section. The spatial information was gained from the line-of-sight intensity signals by means of a tomographic reconstruction technique.

A calibration and validation workflow will be presented in this paper, which utilizes common static global models for fuel consumption, NOx and soot. Due to the applicability for warm-up tests, e.g. New European Driving Cycle (NEDC), the models need to predict the temperature influence and will be fitted with measuring data from a conditioned engine test bed. The applied model structure consisting of a number of global data-based sub-models is configured especially for the requirements of multi-injection strategies of common rail systems. Additionally common global models for several constant coolant water temperature levels are generated and the workflow tool supports the combination and segmentation of global nominal map with temperature correction maps for seamless and direct ECU setting.

Increasing powertrain complexity and the growing number of vehicle variants are putting a strain on current calibration development processes. This is particularly challenging for vehicle drivability calibration, which is traditionally completed late in the development cycle, only after mature vehicle hardware is available. Model-based calibration enables a shift in development tasks from the real world to the virtual world, allowing for increased system robustness while reducing development costs and time. A unique approach for drivability calibration was developed by incorporating drivability analysis software with online optimization software into a virtual engine test cell environment. Real-time, physics-based engine and vehicle simulation models were coupled with real engine controller hardware and software to execute automated drivability calibration within this environment.

Due to its high number of free parameters, the new generation of gasoline engines with direct injection require an efficient calibration process to handle the system complexity and to avoid a dramatic increase in calibration costs. This paper presents a concept of specific toolboxes within a standardized and automated calibration environment, supporting the complexity of GDI engines and establishing standard procedures for distributed development. The basic idea is the combination of a new and more efficient online DoE approach with the automatic and adaptive identification of the region of interest in the high dimensional parameter space. This guarantees efficient experimental designs even for highly non-linear systems with often irregularly shaped valid regions. As the main advantage for the calibration engineer, the new approach requires almost no pre-investigations and no specific statistical knowledge.

In recent years several new gasoline engine technologies were introduced in order to reduce fuel consumption. Controlled autoignition seems to be an alternative to stratified part load operation, which is handicapped due to it's lean aftertreatment system for world wide application. The principal advantages of controlled auto ignition combustion under steady state operation - combining fuel economy benefits similar to stratified charge systems with nearly negligible NOx and soot emissions - are already well known. With the newly developed AVL- CSI system (Compression and Spark Ignition), a precise combustion control is achieved even under transient operation. For compensation of production and operation tolerances a cost optimized cylinder individual control was developed. Completely new functionalities of the engine management system are applied. This lean GDI concept complies with future emission standards without DeNOx catalyst and can be applied worldwide.

The world of automotive engineering shows a clear direction for upcoming development trends. Stringent fleet average fuel consumption targets and CO2 penalties as well as rising fuel prices and the consumer demand to lower operating costs increases the engineering efforts to optimize fuel economy. Passenger car engines have the benefit of higher degree of technology which can be utilized to reach the challenging targets. Variable valve timing, downsizing and turbo charging, direct gasoline injection, highly sophisticated operating strategies and even more electrification are already common technologies in the automotive industry but can not be directly carried over into a motorcycle application. The major differences like very small packaging space, higher rated speeds, higher power density in combination with lower production numbers and product costs do not allow implementation such high of degree of advanced technology into small-engine applications.

This paper presents the results of an investigation on the influence of a duct’s geometry and shape on its acoustic length, which differs from its physical length by a factor referred to as end-correction. In addition to traditional parameters such as length and diameter, the author has investigated the effect of additional geometry features which are less commonly addressed in the technical literature, such as a diameter contraction or a bent section along the duct. The relative microphone position with respect to the pipe orifice and to the ground surface of the measurement environment has been investigated, showing negligible impact on the measurement results. The sound wave propagation within a pipe featuring a diameter contraction has then been analysed, showing the relationship between the pipe contraction shape and location and the pipe acoustic length.

An optical sensor system provides access to standard SI engine combustion chambers via the cylinder head gasket. Flame radiation within the plane of the gasket is observed with optical fibers which are arranged to allow the tomographic reconstruction of flame distribution. The effect of convective in-cylinder air motion generated by variations of inlet ports and combustion chamber geometries on flame propagation is directly visible. A high degree of correlation between flame intensity distribution and NOx emission levels yields a useful assessment of combustion chamber configurations with minimum emission levels. The location of knock centers is identified.

A series of experimental studies of diesel spray and combustion characteristics was carried out using circular, elliptic and step orifices. The experiment was performed on a 3-litre single-cylinder engine with optical access. In the engine tests, an elliptic-orifice nozzle with an aspect ratio of approximately 2:1, and a step-orifice nozzle were compared with circular-orifice nozzles. All orifices had sharp-edged inlets. The nozzles were tested at injection pressures extending from 300 to 1300 bar. The nozzles were evaluated in respect of initial spray tip velocity, penetration, spray cone angle, spray width, intermittency and heat-release. Substantial differences were observed in the spray characteristics: At an injection pressure of 300 bar, the spray width increased twice as fast in the minor axis plane of the elliptic orifice and step orifice than the circular orifices.

The replacement of safety-critical mechanical components with electro-mechanical systems has led to the fact that safety aspects play a central role in development of embedded automotive systems. Recently, consumer demands for connectivity (e.g., infotainment, car-2-car or car-2-infrastructure communication) as well as new advances toward advanced driver assistance systems (ADAS) or even autonomous driving functions make cybersecurity another key factor to be taken into account by vehicle suppliers and manufacturers. Although these can capitalize on experiences from many other domains, they still have to face several unique challenges when gearing up for specific cybersecurity challenges. A key challenge is related to the increasing interconnection of automotive systems with networks (such as Car2X). Due to this connectivity, it is no longer acceptable to assume that safety-critical systems are immune to security risks.

A broad variety of new technologies for improving fuel economy is currently under development or investigation. The general statement is that always a compromise between fuel economy benefit and engine oncost has to be found. This paper describes a new way for improving fuel economy based on existing technologies used in a refined way. It is shown that with very simple and robust measures on the intake and exhaust ports and on the valve train mechanism 2 valve and 4 valve engines can show a significant improvement in fuel consumption without having a great cost penalty for production. The basic system consists of a single cam phaser and a special port arrangement on a 2 valve engine with a single camshaft operated at stoichiometric air/fuel ratio utilizing internal EGR and a reverse “Miller-Cycle”. Variable charge motion is generated using a shared flow through the intake and the exhaust port by varying cam timing.

The application of lightweight materials for new crankcase concepts implies comprehensive design considerations to achieve weight reductions as close as possible to the potential of the selected material. A specific approach for inline and V-engine crankcase concepts is discussed in detail. Engine weight reduction can also be achieved through "Downsizing." Modern technologies applied to existing engine concepts increase the power-weight ratio, the engine''s capability and therefore its marketing value. The use of lightweight materials for diesel and gasoline engines within one engine family allows a combined production and a less costly machining. Aluminum and magnesium alloys are, due to their high relative strength (tensional strength and e-modulus divided by their material densities), suitable for weight-reduced components which need to be designed for a specific target strength.

This paper gives insights in the theoretical measurement uncertainty of E-Drive rotor position dependent results, like Id and Iq calculations, done by a modern propulsion power analyzer (PA). The calculation of Id and Iqis fundamental to perform control optimization and application tasks for an E-Drive system. To optimize the E-Drive system application towards e.g., best efficiency, best performance, or improved NVH the importance of the testing toolchain is described: a power analyzer delivering the required results, an automation system, and a Design of Experiment tool to set improved target values. Consequently, inverters applications featuring field-oriented control (FOC) with permanent magnet synchronous machines (PMSM) are updated with a chosen control strategy. For achieving a certain behavior of an E-Drive, different degrees of freedom in the Inverter Control Unit are available; Lookup tables Id and Iq represent two fundamental application labels to be considered.

An advanced multi-layer material model has been developed to simulate the complex behavior in case-carburized gears where hardness dependent strength and elastic-plastic behavior is characterized. Also, an advanced fatigue model has been calibrated to material fatigue tests over a wide range of conditions and implemented in FEMFAT software for root bending fatigue life prediction in differential gears. An FEA model of a differential is setup to simulate the rolling contact and transient stresses occurring within the differential gears. Gear root bending fatigue life is predicted using the calculated stresses and the FEMFAT fatigue model. A specialized rig test is set up and used to measure the fatigue life of the differential over a range of load conditions. Root bending fatigue life predictions are shown to correlate very well with the measured fatigue life in the rig test.

With upcoming emission regulations particle emissions for GDI engines are challenging engine and injector developers. Despite the introduction of GPFs, engine-out emission should be optimized to avoid extra cost and exhaust backpressure. Engine tests with a state of the art Miller GDI engine showed up to 200% increased particle emissions over the test duration due to injector deposit related diffusion flames. No spray altering deposits have been found inside the injector nozzle. To optimize this tip sooting behavior a tool chain is presented which involves injector multiphase simulations, a spray simulation coupled with a wallfilm model and testing. First the flow inside the injector is analyzed based on a 3D-XRay model. The next step is a Lagrangian spray simulation coupled with a wallfilm module which is used to simulate the fuel impingement on the injector tip and counter-bores.

Electrification globally shows promise in reducing greenhouse and noxious emissions. Although there is immense potential in such technologies penetrating across vehicle segments in the Indian market, the key lies in offering scalable, cost effective battery solutions suiting the diverse product and customer needs. This paper describes the development and possible applications of a low voltage battery system that fulfills the current needs on the Indian market. Based on real-world driving profiles the energy and power output required for the target platform are determined. Keeping in mind the Indian operating conditions, safety requirements, driving behavior, charging infrastructure, operational costs, supplier network and serviceability, technical requirements for such systems are described. Also, benchmarking data of current battery systems help to optimize the mechanical, thermal, and electrical layouts.