To enhance the insulating properties of a thermal barrier coating, one has to focus on new materials with lower intrinsic thermal conductivity than established yttria-stabilized zirconia. Substances with pyrochlore structure were investigated. Starting from lanthanum zirconate, substitutions of the lanthanum by other trivalent rare-earth elements were made, and the thermal conductivity and the thermal expansion coefficient of the manufactured materials were measured. A complete substitution of the lanthanum led to increased thermal expansion coefficients, whereas the partial substitution did not show an appreciable effect. The thermal conductivities of the modified materials were lower than that of the pure lanthanum zirconate for temperatures <1000°C for all amounts and elements of substitution. A comparison of the observed values with calculated values of the thermal conductivities showed a relatively good agreement.N. Padture-contributing editor Manuscript No. 186991.

In application as a thermal barrier coating (TBC), partially stabilized zirconia (Zr) approaches some limits of performance. To further enhance the efficiency of gas turbines, higher temperature capability and a longer lifetime of the coating are needed for the next generation of TBCs. This paper presents the development of new materials and concepts for application as TBC. Materials whose compositions have the pyrochlore structure or doped Zr are presented in contrast with new concepts like nanolayers between the top and bond coat, metal-glass composites, and double-layer structures. In the last concept, the new compositions are used in a combination with Zr, as a double, multi, or graded layer coating. In this case, the benefits of Zr will be combined with the promising properties of the new top coating. In the case of metal-glass composites, the paper will be focused on the influences of different plasma spraying processes on the microstructure. The performance of all these different coating systems has been evaluated by burner rig tests. The results will be presented and discussed.

Today's large-scale scientific simulations generate massive data sets that pose challenges both for data storage in HPC environments dur ing the simulation phase and the subsequent data analysis phase. A promising approach for reducing the amount of data written out dur ing simulation run is in-situ compression. However, even the com pressed data sets are typically still too large for interactive visual data exploration which calls for multi-resolution data layouts. The recently proposed ISABELA method for lossy in-situ compression was shown to outperform other compression methods for scientific data sets. In this paper, we propose two main extensions to the IS ABELA method: (1) an interlaced data layout that supports decom pression of multi-resolution views of the data without overhead in the compressed format; (2) a new temporal compression scheme for improving the compression rate by exploiting temporal coherence in the data set. The compressed multi-resolution data can easily be transformed to the VTK AMR (adaptive multi-resolution) data for mat to support interactive exploration in Para View and other visu alization tools based on VTK. During the simulation phase, there is no significant increase of computational demands for the generation of complete multi-resolution compressed data sets as compared to fiat ISABELA compression. During the analysis phase, due to the AMR data layout, our method supports selective loading of regions of interests as well as progressive loading of data sets, thus enabling interactive visualizations of large-scale scientific simulations.

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