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In the next 20 years the share of small electric vehicles (SEVs) will increase especially in urban areas. SEVs show distinctive design differences compared to traditional vehicles. Thus the consequences of impacts of SEVs with vulnerable road users (VRUs) and other vehicles will be different from traditional collisions. No assessment concerning vehicle safety is defined for vehicles within European L7e category currently. Focus of the elaborated methodology is to define appropriate test scenarios for this vehicle category to be used within a virtual tool chain. A virtual tool chain has to be defined for the realization of a guideline of virtual certification. The derivation and development of new test conditions for SEVs are described and are the main focus of this work. As key methodology a prospective methodical analysis under consideration of future aspects like pre-crash safety systems is applied.

In this paper a new numerical methodology to compute component temperatures of a rotating cardan shaft is described. In general temperatures of the cardan shaft are mainly dominated by radiation from the exhaust gas system and air temperatures in the transmission tunnel and underbody. While driving the cardan shaft is rotating. This yields a uniform temperature distribution of the circumference of the shaft. However most simulation approaches for heat protection are nowadays steady-state computations. In these simulations the rotation of the cardan shaft is not considered. In particular next to the exhaust gas system the distribution of the temperatures of the cardan shaft is not uniform but shows hot temperatures due to radiation at the side facing the exhaust gas system and lower temperatures at the other side. This paper describes a new computational approach that is averaging the radiative and convective heat fluxes circumferentially over bands of the cardan shaft.

Future CO2 emission legislation requires the internal combustion engine to become more efficient than ever. Of great importance is the boosting system enabling down-sizing and down-speeding. However, the thermodynamic coupling of a reciprocating internal combustion engine and a turbocharger poses a great challenge to the turbine as pulsating admission conditions are imposed onto the turbocharger turbine. This paper presents a novel approach to a turbocharger turbine development process and outlines this process using the example of an asymmetric twin scroll turbocharger applied to a heavy duty truck engine application. In a first step, relevant operating points are defined taking into account fuel consumption on reference routes for the target application. These operation points are transferred into transient boundary conditions imposed on the turbine.

This paper investigates the pressure drop with and without condensation inside a charge air cooler. The background to this investigation is the fact that the stored condensate in charge air coolers can be torn into the combustion chamber during different driving states. This may result in misfiring or in the worst-case lead to an engine failure. In order to prevent or reduce the accumulated condensate inside charge air coolers, a better understanding of the detailed physics of this process is required. To this end, one single channel of the charge air side is investigated in detail by using an experimental setup that was built to reproduce the operating conditions leading to condensation. First, measurements of the pressure drop without condensation are conducted and a good agreement with experimental data of a comparable heat exchanger reported in Kays and London [1] is shown.

The reduction of fuel consumption as well as the rising demands of customers regarding a vehicle’s driving dynamic and the legislator’s continually rising demands are a current issue in vehicle development. Hybrid vehicles offer a possibility to rise to this challenge. Realistic driving cycles are of utmost importance for the calibration of a hybrid vehicle’s operational strategy. Deriving replacement speed cycles from extensive customer data sets seems to be an approach for solving these problems. The contribution at hand describes the derivation of replacement cycles by using stochastic models, probabilistic (weighted) drawings and a combinatorial optimisation. The novelty value is that the characteristic influences of all drivers are being considered in the generation due to the stochastic modelling.

NH₃/urea SCR is a very effective and widely used technology for the abatement of NOx from diesel exhaust. The SCR mechanism is well understood and the catalyst behavior can be predicted by mathematical models - as long as operation above the temperature limit for AdBlue® injection is considered. The behavior below this level is less understood. During the first seconds up to minutes after cold start, complete NOx abatement can be observed over an SCR catalyst in test bench experiments, together with a significant increase in temperature after the converter (ca. 100 K). In this work these effects have been investigated over a monolith Cu-zeolite SCR catalyst. Concentration step experiments varying NO, NO₂ and H₂O have been carried out in lab scale, starting from room temperature. Further, the interaction of C₃H₆ and CO with NOx over the SCR has been investigated.

The increasing functionality and complexity of future electric/electronic architectures requires efficient methods and tools to support design decisions, which are taken in early development phases 6. For the past four years, a holistic approach for architecture development has been established at Mercedes-Benz Cars R&D department. At its core is a seamless design flow, including the conception, the analysis and the documentation for electric/electronic architectures. One of the actual challenges in the design of electric/electronic architectures concerns communication behavior and network topologies. The increasing data exchange between the ECUs creates high requirements for the networks. With the introduction of FlexRay 21 and Ethernet the automotive network architecture become a lot more heterogeneous. Especially gateways must fulfill many new requirements to handle the strict periodic schedule of FlexRay and the partly event-triggered communication on CAN-busses 23.