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Das Betriebsverhalten von Wellenleistungsgasturbinen zum Antrieb von Hubschraubern hängt stark vom Zustand der Luftströmung am Eintritt ab. In der hier vorliegenden Arbeit werden die Auswirkungen wechselnder Gaszusammensetzungen auf das Triebwerk untersucht. Eine wesentliche Gefahr stellt das Verlöschen der Brennkammer infolge Sauerstoffmangels dar. Der Einsatz spezieller Sensoren an einem Triebwerk ermöglicht die Integration zusätzlicher Funktionen in die elektronische Triebwerksregelung, die zur Verbesserung des Betriebsverhaltens und damit zur Sicherheit beitragen. The performance of gas turbines for helicopters strongly depends on the quality of the airflow at the engine intake. This thesis thoroughly investigates the effects of a changing gas composition on the engine. The risk of a flame out of the combustion chamber due to the lack of oxygen in the intake air poses a major danger for flight safety. With the use of special sensors, additional functions are added to the electronic control system to enhance engine performance and improve flight safety.

Zirconium oxide Zr02, as an important representative of advanced ceramic materials, has outstanding mechanic, refractory, and electrochemical properties. In addition to its wide use in ultra-strong stabilized zirconia tools and as an ion conducting electrolyte in oxygen sensors, pumps, and fuel cells, it has recently been examined for use in ceramic automotive engines and as a support for high temperature catalysts (1,2). Zirconia plays also a crucial role in nuclear reactors as a protective oxide layer on various zirconium-alloy components, such as fuel cladding, fuel channels and pressure tubes. It appears that iron impurities in zirconia may seriously affect the properties of the zirconia-based ceramics as well as the oxida¬tion characteristics of zirconium alloys (3–5). However, unlike the Zr-Fe alloy system, which is rather well established (6), the knowledge of the ternary Zr-Fe-0 system is still in its infancy (7,8). Therefore, detailed understanding of the state of iron in zirconia, and — particularly — its role in oxygen and hydrogen transport, is of primary interest.