The hydrogenation of p-nitrotoluol to p-toluidin was done both in a fixed bed reactor and in a microchannel reactor made of a stack of micro structured aluminum wafers. Two procedures for the deposition of the catalytic active component palladium on the microstructured aluminum wafers are described. The hydrogenation results are discussed. Advantages and drawbacks of both reactor types are shown.

This abstract deals with thermal energy stores for solar and district heat supply systems and presents numerical results for the performance of radial diffusers in a new type of overground storage tank which has a floating ceiling. The influence of the position of the radial diffuser in the thermal store was investigated revealing significant potentials regarding thermal stratification and storage efficiency. The optimization of the diffuser geometry led to a new free-form radial diffuser, which allows charging temperatures up to 98 °C. A Large Eddy Simulation (LES) illustrated the development of the stratification.

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Residence time distributions (RTD) are often described on the basis of the dispersion or the tanks in series models, whereby the fitting is not always good. In addition, the underlying ideas of these models only roughly characterize the real existing processes. Two semi-empirical equations are presented based on characteristic parameters (mean, minimum, maximum residence time) and on an empirical exponent to permit better fitting. The determination of the parameters and their influence on the RTD are discussed. The usefulness of the models is shown in this first part for single-phase systems and for the continuous phase of multiphase systems using data from literature for laminar and turbulent flows in different apparatuses. A comparison with the results of other models is also done.

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Radialdiffusoren dienen der Be‐ und Entladung von thermischen Speichern und beeinflussen signifikant die Qualität der thermischen Schichtung. Zur Verbesserung der Schichtungsqualität ist das Verständnis der komplexen Strömungsvorgänge notwendig. Gegenstand von Teil 1 der Veröffentlichungsreihe ist die Simulation einer isothermen Strömung im Radialdiffusor unter besonderer Beachtung der Strömungsvorgänge in der Einlaufstrecke sowie der Grenzschichtbehandlung. Nur bei einer sehr guten Auflösung der Grenzschichtströmung ist ein symmetrisches Ausströmen festzustellen.

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