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In current research projects such as "Vehicle to Grid" (V2G), "Vehicle to Building" (V2B) or "Vehicle to Home" (V2H), plug-in vehicles are integrated into stationary energy systems. V2B or V2H therefore stands for intelligent networking between vehicles and buildings. However, in these projects the objective is mostly from a pure electric point of view, to smooth the load profile on a household level by optimized charging and discharging of electric vehicles. In the present paper a small energy system of this kind, consisting of a building and a vehicle, is investigated from a holistic point of view. Thermal as well as electrical system components are taken into account and there is a focus on reduction of overall energy consumption and CO₂ emissions. A predictive energy management is presented that coordinates the integration of a plug-in hybrid electric vehicle into the energy systems of a building. System operation is optimized in terms of energy consumption and CO₂ emissions.

A 2-step valve train offers a cost effective alternative to fully variable valve trains. Using the small valve lift, which is usually combined with an early intake closing strategy, reduced pumping losses are opposite to decreasing combustion efficiency due to lower charge motion. To work out the trade off between these two effects an extensive coupled CFD investigation is performed. The 1-D engine model delivering the pumping losses is complemented by an empirical combustion model, that relates combustion duration with residual trapped gas content. The model ensures right prediction of fuel economy. Additionally the influence of a small intake valve event on charge motion can also be demonstrated by 3-D in-cylinder flow simulation.

DVCP, a system with continuously adjustable intake and exhaust cam positions, was investigated in terms of residual gas content, intake manifold pressure, pumping losses and fuel economy by means of engine cycle simulation on a 16-valve 4 cylinder naturally aspirated SI engine at part load conditions. Using the simulation results a phasing strategy for part load operation with the primary emphasis on improved fuel consumption has been developed. To verify simulation predictions subsequently, measurements were made at the test rig. It was found that cycle simulation was able to predict properly the behavior of the engine even far away from calibration point. The simulated and measured cam positions for maximum fuel economy matched. Test rig results showed that fuel economy improvement by DVCP is limited by residual gas content tolerance of the engine investigated.

The COLUMBUS APM employs CO2 stored in centralized tank or, as backup, in portable fire extinguishers (PFEX) for the suppression of eventual fire events. The conditions of the 2-phase flow of the CO2 in the tank and in the ducting system are an important parameter for the layout of the system. In this paper the analytical and experimental work performed to determine these flow conditions and the results for the baseline fire suppression system shall be given.