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Novel laser sensor allows for precise tip clearance and vibration measurements of turbo-machines The Technische Universität Dresden (TU Dresden) and the German Aerospace Center (DLR) have cooperated in developing a novel laser sensor which measures two quantities that are important for turbine engineering more precise than ever before: firstly, the tip clearance between the rotating blades and the turbine casing over and, secondly, the vibrations resulting from the blades’ supersonic velocity. The scientists applied the laser Doppler technology, developing a sensor which allows for the mathematical calculation of the tip clearance via the electronic signal processing of two different Doppler frequencies – instead of one – which are generated by two separate laser wavelengths.
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