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Compared with the traditional bench testing approach, the virtual validation on a PC is more time-saving and cost-effective. However, the control software of an electronic control unit is typically developed together with suppliers and original equipment manufacturer, and each owns parts of the source code. So it is impossible to set up a simulation based on the original C code. Alternatively, to set up an equivalent model is usually time-consuming and less effective. In this work, Schaeffler describes how to develop a virtual testing method based on chip simulation for the series produced mechatronic active roll control system.

With the continuous growth in the emission requirements and higher riding comfort demand, the shift quality becomes more and more an important evaluation index of the automated transmission control algorithms. Traditionally, the shift quality is assessed subjectively by the driver's feeling and then adjusted based on the calibration engineer experience. This classical calibration has disadvantages, such as low reproducibility of the shifting event and a high dependence on the driver's driving habit, so here a model-based multi-objective optimization method is proposed, and the optimization of the clutch control parameters during the vehicle starting is used as an example. Firstly, a Modelica® based vehicle model is introduced. A second-order sliding mode control is applied to track the clutch position trajectory. The clutch engagement point and the clutch engagement speed in the slipping stage are taken as the optimization objects.

The new opoc™ diesel engine concept was presented at the SAE 2005 World Congress [1]. Exceptional power density of >1hp/lb and >40% efficiency have been predicted for the 2-stroke opoc™ diesel engine concept. Intensive CAE simulations have been performed during the concept and design phase in order to define the baseline scavenging and combustion parameters, such as port timing, turbocharger configuration and fuel injection nozzle design. Under a DARPA contract, first prototype engines have been built and have undergone a validation testing program. The main goal of the first testing phase was to demonstrate the power output capability of the new engine concept. In close relationship and interaction of testing and CAE simulation, the uniflow scavenging process and parameters of the special diesel direct side injection have been optimized. This paper discusses the latest results of the opoc engine development.

The opposed piston opposed cylinder (opoc™) engine concept has been demonstrated as an engine concept with high specific power density and high power to volume ratio. The engine has several potential applications, including use as an auxiliary power unit (APU) in various commercial and military applications and as the primary power source for small unmanned air vehicles (UAVs). An engine in this power range operating on heavy fuels (e.g. JP5, JP8, DF2) is not typically available. The engine uses a two-cycle supercharged uniflow scavenging system with asymmetric port timing and will run at speeds between 8,000 and 12,000 rpm. The unique design of the opoc™ engine produces a piston speed that is half the speed of a typical crankshaft engine running at the same speed. Uniflow scavenging produces gas exchange efficiencies rivaling those of four-cycle engines. The design also leads to reduced in-cylinder heat losses. Furthermore, the opoc™ engine is fully balanced.

The purpose of this study is to predict droplet breakup characteristics and spray characteristics of intermittent butane injection. In this study attention was paid to the breakup of liquid and droplet collision in order to quantify the spray formation and development in a furnace. The predicted results were compared with the experimental results obtained by a phase Doppler anemometer (PDA). It could help to determine the spray pattern, arrival distance, droplet diameter distributions, Sauter mean diameter, and vapor concentration in the butane injection.