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Collecting spatially resolved gas phase concentration profiles in catalytic monoliths by applying suction probe techniques has become an important tool for understanding the reaction sequence and for optimizing the design of structured catalysts. The impact of the capillary on the data is investigated by means of computational fluid dynamics (CFD) simulations using the exemplary cases of catalytic partial oxidation of methane over rhodium and oxidation of carbon monoxide over palladium. The influence of a suction probe inside a rectangular channel of a monolith on flow field and concentration profiles are discussed. Four different configurations were investigated: probe in center or corner of the channel with insertion from upstream or downstream in each case. If the capillary is located in the corner of the channel, the influence on the data is negligible. For a position in the center, a noticeable impact was observed. A simple analytical model can predict the reduction of the mass flux due to the insertion of the probe. The worst case exhibits a reduction >50 %. The measuring error is dependent on the direction of insertion of the capillary into the channel (upstream or downstream). Additionally, axial diffusion plays a significant role. For any interpretation of the data, the influence of the probe on the measured data has to be considered. The quantification of the error requires three-dimensional CFD simulations.

Fixed bed reactor simulations are often based on a porous media model with a single energy equation for the combined fluid and solid phases. In this energy equation, an effective thermal conductivity (which takes into account both the fluid and solid properties) is typically utilized. DUO (DETCHEM und OpenFOAM) has been extended to model porous media reactions in 1D and 2D, including the effects of packed bed effective thermal conductivity and intra-particle diffusion. For the 1D model, correlations for the wall Nusselt number and the overall heat transfer coefficient are used to capture radial heat transfer effects. With these approaches, reactor simulation times have been reduced from hundreds or thousands of core hours required for 3D Particle Resolved Computational Fluid Dynamics (PRCFD), to core minutes/hours for a 2D porous media model, to core seconds/minutes for a 1D porous media model, while maintaining fidelity to the 3D CFD and experimental comparison data sets. Supporting examples include catalytic steam methane reforming, catalytic dry reforming of methane, and heat transfer in an empty tube.

From analytical investigations it is well known that the roll-up of an inviscid plane vortex sheet which separates at the edge of a body is a self-similar process which can be described by scaling laws. Unlike plane vortices, ring vortices have a curved rotational axis. For this special vortex type experimental investigations as well as calculations in the literature suggest that the scaling laws are only partially valid. The main goal of this work is to clarify how far these similarity or scaling laws are also valid for the formation of viscid laminar vortex rings. Therefore, the formation process of laminar vortex rings was investigated numerically using a CFD (computational-fluid-dynamics) code. The calculations refer to an experimental setup for which detailed experimental data are available in the literature. In this setup, laminar ring vortices are generated by ejecting water from a circular tube into a quiescent environment by means of a piston. First, a case based on a constant piston velocity was investigated. Comparing calculated and measured data yields a very good agreement. Further calculations were made when forcing the velocity of the piston by three different time-dependent functions. The results of these calculations show that the formation laws for inviscid plane vortices are also valid for the formation process of viscid ring vortices. This applies to the normalized axial and radial position of the vortex centre as well as the normalized diameter of the vortex spiral. However, the similarity laws are valid only if the process is considered in a special frame of reference which moves in conjunction with the front of the jet and if the starting time of the formation process with respect to the starting time of the ejection is taken into account. Additionally, the formation of a ring vortex, which occurs during the start-up process of a free jet flow, was calculated. The results confirm a dependence for the motion of the jet front, which is known from analytical considerations and allows some interesting features to be identified.

Validation and optimization of technical systems are central activities in the product development process. One part of it is the calibration and validation on a level, which covers the whole vehicle. The aspect, that plays the most important role in both validation and optimization, is the driving condition. Especially in the case of hybrid vehicles, state variables like the state of charge (SOC) have great influence on the operating strategy and therefore on assessment criteria.The article’s objective is to present a procedure, which performs the conditioning and brings the planned maneuver into an order, which reduces the total needed conditioning duration. Thereby a lot of time can be saved, according to the type and amount of the possible maneuver and state values. In addition to optimizing the order of conventional maneuver, the procedure can be used to optimize the list of maneuver in a DOE-Plan. Thereby the maneuver of the individual criteria can be re-sorted as well as the designparametervariation. The IPEK-X-in-the-Loop framework (XiL) is the basis for the approach and will be used as a validation environment in an acoustic roller test bench with vehicle-in-the-loop technology.