The NASA rotor 37 is investigated accounting for as many as 9 simultaneous operational and geometrical uncertainties. The combined influence of uncertainties on input quantities such as the total inlet pressure, static outlet pressure, tip gap or leading and trailing edge angles on output quantities is studied. These simulations provide results which go far beyond the standard deterministic simulation. A probabilistic collocation method in combination with a sparse grid quadrature is introduced into the software suite FINE™ propagating combined operational and geometrical uncertainties in complex 3D CFD simulations. The modification of the parameterized geometry and the consequent re-meshing is provided by a fully automatic tool, which also couples with the flow solver and provides post-treatment routines. It is this automation, which makes this kind of study feasible. A manual modification of geometry, manual meshing and simulation set-up accounting for a multitude of simultaneous uncertainties is simply unfeasible for as many as hundreds of complex 3D turbo-machinery simulations. This work represents thus a break-through in the uncertainty management towards the application of uncertainty propagation in the daily engineering practice.

A time driven Lagrangian particle detection algorithm for a poly-dispersed mixture of particles is developed and validated. The advantage of this algorithm is the possibility to treat a distribution of particle diameters. We are especially interested in the collision treatment of poly-dispersed particle mixtures and coalescence. Particle pairs are found by applying the overlap criteria and additionally another second criterion, which allows a substantial increase of the time step without limiting the algorithm’s accuracy. The algorithm, which is developed here, is validated with test cases by comparison with predictions of the kinetic theory of rarefied gases. They are applied to dry granular flows. The algorithm accuracy is determined with respect to time step criteria, for both dilute and dense systems.

This paper describes alternative low-temperature bonding procedures in Microsytems Technology. On the one hand reactive bonding is introduced, which is a relatively new joining technique for the mounting of microelectric components and the hermetic sealing of microelectronic packages. The usage of commercially available Ni/Al foils is demonstrated for room-temperature bonding an IR-emitter onto a covar socket. Furthermore integrated nano scale multilayer films of aluminum and titanium as well as titanium and amorphous silicon were magnetron sputter deposited and characterized. On the other hand surface activating procedures prior to bonding, like low- and atmospheric-pressure plasma, are presented. The wafer level bonding was examined for silicon to lithium tantalate (LiTaO3) and Foturan{copyright, serif} by using CMP-processes and plasma activation. The bond strength was characterized by micro chevron test to evaluate the different bonding, plasma and annealing conditions. The results showed that with the surface activation the bond strength can be dramatically enhanced.

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