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The number of full electric and hybrid electric vehicles is rapidly growing [1][2][3]. The new technologies accompanying this trend are increasingly becoming a focal point of interest for rescue services. There is much uncertainty about the right techniques to free trapped occupants after an accident. The same applies to vehicle fires. Can car fires involving vehicles with a lithium ion traction battery be handled in the same way as conventional vehicle fires? Is water the right extinguishing agent? Is there a risk of explosion? There are many unanswered questions surrounding the topic of electric vehicle safety. The lack of information is a breeding ground for rumours, misinformation and superficial knowledge. Discussions on various internet platforms further this trend. Tests were conducted on three lithium ion traction batteries, which were fuel-fired until burning on their own. The batteries were then extinguished with water, a surfactant and a gelling agent.

For medium- and heavy-duty diesel engines, the development of new catalyst technologies and particulate filters is necessary to fulfill increasingly stringent emission regulations. An important aspect is the durability of the after-treatment system and therefore its efficiency over lifetime. Lubrication oil additives contain components such as phosphorous or zinc to ensure engine durability. Diesel oxidation catalyst (DOC) and coated diesel particulate filter (cDPF) catalytic coatings are negatively influenced by contamination on the surface with these components (chemical ageing). The components have a negative impact on the exhaust after-treatment systems performance. Additionally the cDPF is filled with oil ash. Engine tests are conducted to analyze the effect of lubrication oil additives on after-treatment system performance. In one study, lubrication oil with increased sulfur ash content is used.

The real cycle simulation is an important tool to predict the engine efficiency. To evaluate Extended Expansion SI-engines with a multi-link cranktrain, the challenge is to consider all concept specific effects as best as possible by using appropriate submodels. Due to the multi-link cranktrain, the choice of a suitable heat transfer model is of great importance since the cranktrain kinematics is changed. Therefore, the usage of the mean piston speed to calculate a heat-transfer-related velocity for heat transfer equations is not sufficient. The heat transfer equation according to Bargende combines for its calculation the actual piston speed with a simplified k-ε model. In this paper it is assessed, whether the Bargende model is valid for Extended Expansion engines. Therefore a single-cylinder engine is equipped with fast-response surface-thermocouples in the cylinder head. The surface heat flux is calculated by solving the unsteady heat conduction equation.

The increasing shift of drive operation towards efficient engine operation points at very low engine speeds demands a concerted design and tuning of engine, drive-train, assembly attachment and body to avoid annoying low speed boom noise. An additional challenge in this area of conflict is the increasing torque of modern engines at low engine speeds. As an example for a standard passenger car, the modes of operation, which may lead to low speed boom noise, are described. Setting levers along the complete chain of effect are characterised - from cylinder pressure up to the radiating surfaces of the interior. To achieve challenging NVH-targets the application of nonlinear simulation systems is indispensable, in particular in the concept phase of a vehicle. The use of multi-body simulation is presented for a concentrated NVH-optimisation of powertrain and rear axle vibration behaviour to reduce low-speed boom noise. On entire vehicle level hybrid simulation models are useful.

Downsizing and direct injection in modern DISI engines can lead to fuel impinging on the cylinder walls. The interaction of liquid fuel and engine oil due to fuel impinging on the cylinder wall causes problems in both lubrication and combustion. To analyze this issue with temporal and spatial resolution, we developed a laser-induced fluorescence (LIF) system for simultaneous kHz-rate imaging of fuel and oil films on the cylinder wall. Engine oil was doped with traces of the laser dye pyrromethene 567, which fluoresces red after excitation by 532 nm laser radiation. Simultaneously, the liquid fuel was visualized by UV fluorescence of an aromatic “tracer” in a non-fluorescent surrogate fuel excited at 266 nm. Two combinations of fuel and tracer were investigated, iso-octane and toluene as well as a multi-component surrogate and anisole. The fluorescence from oil and fuel was spectrally separated and detected by two cameras.

The use of twin-scroll turbocharger turbines has gained popularity in recent years. The main reason is its capability of isolating and preserving pulsating exhaust flow from engine cylinders of adjacent firing order, hence enabling more efficient pulse turbocharging. Asymmetrical twin-scroll turbines have been used to realize high pressure exhaust gas recirculation (EGR) using only one scroll while designing the other scroll for optimal scavenging. This research is based on a production asymmetrical turbocharger turbine designed for a heavy duty truck engine of Daimler AG. Even though there are number of studies on symmetrical twin entry scroll performance, a comprehensive modeling tool for asymmetrical twin-scroll turbines is yet to be found. This is particularly true for a meanline model, which is often used during the turbine preliminary design stage.

Lubricant oil derived ash deposits still represent a major issue in diesel particulate filter operation in vehicles. In literature various ash deposition patterns are described. The two boundary deposition patterns are (a) wall layer and (b) filling at the back end of the inlet channels. The patterns are often associated with different regeneration methods. Continuous regeneration is supposed to result in a homogeneous ash layer, whereas periodic (active) regeneration is reported to result in back end filling. The current contribution describes the basic mechanisms associated with ash transport phenomena in particle filters. On the basis of (a) frequency of ash exposure to flow (b) ash particle structure re-entrainment and finally (c) axial ash transport the different deposition pattern can be explained. Exposure to flow accomplished by periodical soot removal, either by passive or active regeneration is the first step.

In the proposed work the transient thermal modeling of a vehicle cabin has been performed. Therefore, a reduced model has been developed based on a one-node discretization of the cabin air. The conduction in the solid parts is accounted for by a one-dimensional heat transfer approach, the radiation exchange between the surfaces is based on view factors adopted from a 3D reference and the convective heat transfer from the cabin surfaces to the cabin air is conducted with the help of heat transfer coefficients calculated in a 3D reference simulation. The cabin surface is discretized by planar wall elements, including the outer shell of the cabin and inner elements such as seats. Each wall element is composed of several homogeneous material layers with individual thicknesses. Investigations have been conducted on the temporal and spatial resolution of the layer structure of these wall elements, for the 3D model as well as for the reduced one.

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.