Diesel-elektrischer Hybridantrieb für kommunale Arbeitsmaschinen

Angepasste Hybridantriebe in mobilen Arbeitsmaschinen (off-highway Anwendungen) versprechen wegen der typischerweise auftretenden Lastzyklen mit ausgeprägten, häufigen und schnellen Laständerungen folgende Vorteile: geringerer Kraftstoffverbrauch, Einsatz eines Dieselmotors kleinerer Leistung, dadurch Erfüllung strikter werdender Emissionsvorschriften (TIER 4, EURO 5) ohne oder mit reduzierter Abgasnachbehandlung, Lärmreduktion, weitere Einsparpotenziale durch Elektrifizierung der Fahrzeugfunktionen möglich (Erhöhung des Hybridisierungsgrads), höhere Produktivität durch höhere Antriebsdynamik.Several duty cycles have been performed with the LADOG multipurpose community vehicle equipped with a conventional diesel engine drive train. Based on these results, simulation calculations have been performed to estimate the fuel savings which can be achieved if this mobile machine would be equipped with a parallel diesel-electric hybrid drive train. Two hybrid configurations were considered, one with the original diesel engine and one with a right-sized, i.e. a smaller diesel engine. Several operation modes of the hybrid were simulated like start-stop function, recuperation, boosting and diesel engine operation for optimized fuel consumption (characteristic mapping). The simulation results showed fuel savings up to 20 % even for this community vehicle which seemed not to be attractive for hybridization. This LADOG vehicle is actually modified by the hybrid drive train substituting the pure diesel drive train. The experimental proof of the simulations is under way

Variable Speed Generators with High Fuel Savings

Auxiliary power units (APUs) are used in mobile applications to supply electrical power in the range of 3 to 10 kW. The state of the art generators are driven by a diesel engine at constant speed. They have a low efficiency (high fuel consumption) as they operate mostly in partial load conditions. A higher efficiency for partial loads is feasible by adjusting the speed of the diesel engine to its optimum efficiency. A frequency converter provides a constant electric frequency at variable speed of the generator. The resulting higher investments for such a variable speed generator (VSG) need a proof of economics, which is demonstrated by this investigation

Hybrid Drive Systems for Industrial Application

Hybrid drives for automotive application are extensively discussed. In contrast, the company HEINZMANN, the University of Karlsruhe and the University of Applied Sciences Offenburg concentrate on hybrid drives for industrial, offroad purposes in a joint project. These applications promise a much higher fuel saving potential, particularly if highly frequent load cycles are present. Hybrid drive systems offer additional advantages including reduced exhaust aftertreatment requirements due to engine downsizing, better engine dynamics, emissions and noise reduction.Hybridantriebe bieten nicht nur im automobilen Bereich Vorteile, vielmehr kann dieses Prinzip im industriellen Bereich seine Vorteile sogar viel besser nutzen. Im Vergleich zu den etablierten Antriebssystemen sprechen zunächst die erhöhte Systemkomplexität, die Entwicklungskosten und das generelle Risiko beim Einsatz neuer Technologien gegen den Hybridantrieb, jedoch punktet dieser mit Einsparungen beim Kraftstoffverbrauch, beim reduzierten Aufwand der Abgasnachbehandlungund bei der zusätzlichen Flexibilität für die Anwendung. So kann sich der Hybridantrieb in der Industrie durchaus rechnen, insbesondere, wenn schnelle Lastwechsel vorliegen

Equalization of the Concentration of a Scalar Impurity in a Flow‐Type Chamber

Experimental and theoretical investigations of the time of equalization of the concentration of an impurity in a rectangular flow‐type chamber have been carried out. It has been shown that the process of equalization of the concentration with time is exponential in character. The characteristic equalization time has been computed using the theory of turbulent diffusion. Theoretical results describe experimental regularities with an accuracy of about 10%. The value of the coefficient of turbulent diffusion for different configurations of flows in the chamber has been obtained from a comparison of experimental and calculated results

Newly designed flow field-flow fractionation channel for macromolecules and particles in the submicrometer and micrometer range

The flow field-flow fractionation (FIFFF) technique is a promising method for separating and analysing particles and large size macromolecules from a few nanometers to approximately 50 μm. A new fractionation channel is described featuring well defined flow conditions even for low channel heights with convenient assembling and operations features. The application of the new flow field-flow fractionation channel is proved by the analysis of pigments and other small particles of technical interest in the submicrometer range. The experimental results including multimodal size distributions are presented and discussed

Correlation of Measurements of a New Long Optical Path Length Particle Sensor against Gravimetric and Electrical Mobility based Particle Measurements in Diesel Exhaust

A prototype multiwavelength sensor able to characterise soot emissions in Diesel exhaust in terms of size and concentration has been tested against other methods for diesel particle measurements like electrical mobility sizing (SMPS) and raw exhaust gravimetric sampling (RES). Measurements carried out with the prototype sensor were correlated with the SMPS by assuming spherical and/or fractal aggregate morphology of the particles. Correlation of RES gravimetric data against the sensor and the SMPS led to the calculation of the solid density for soot particles to be 2.3 gr/cm3

Analysis of Soot Particles Emitted from a Modern Light Duty Diesel Engine Running in Different Operating Conditions using Field Flow Fractionation and Granulometric Techniques

Soot particles emitted from a light duty (LD) Volkswagen diesel engine running at different operating points (speed and torque levels) are analyzed for mean size determination using a laser‐based three Wavelength Extinction Method (3‐WEM). For this reason, collected soot samples are suspended using an appropriate sample preparation technique with optimized conditions of sonication as it revealed its effect on the soot mean particle size measured by 3‐WEM. An online Scanning Mobility Particle Analyzer (SMPS) is also used to measure soot emission at identical engine operating points. Size values obtained from SMPS are lower than those of suspended soot samples obtained from 3‐WEM. The size discrepancies are mainly related to the required sample preparation procedure employed for 3‐WEM measurements. The engine operating points affect, differently, the size measurements obtained from SMPS and 3‐WEM. Sedimentation Field‐Flow Fractionation (SdFFF) is used for density determination of soot samples based on size measurements of fractions collected at peak maxima of fractograms using the off‐line hyphenation with 3‐WEM. It is assumed that a size dependent separation of soot particles occurred with a uniform particle density over the whole size distribution. An average density value is used for the conversion of soot fractograms to size distributions. Discrepancies are also found with size distribution profiles obtained from SMPS for the same engine operating points, due to the sample preparation procedure employed for SdFFF measurements