Societe Nationale D'etude Et De Construction De Moteurs D'aviation

Societe Europeenne De Propulsion

Jacky Y Rouhet

Georges Boulon

Gilbert M Tribillon

Stephane F Bertrand

Michel Clement

The present invention relates to a device for optically measuring the temperatures of cryogenic fluids or of moving surfaces in such fluids by analyzing the decay in the luminescence of a doped crystal, the device comprising a light source for exciting said crystal, an optical fiber for transporting the light flux emitted by said source to the crystal and for returning to a detection assembly the luminescent light emitted by the crystal as a result, and a measurement probe past which the fluid or the moving surface moves, wherein the doped crystal is constituted by one of the crystals from the group comprising strontium fluoride doped with divalent ytterbium, SrF.sub.2 :Yb.sup.2+ ; and calcium fluoride doped with divalent ytterbium, CaF.sub.2 :Yb.sup.2+. In a preferred embodiment for measuring the temperatures of moving surfaces, the measurement probe includes a fiber for transmitting the light flux emitted by the light source plus at least one receiver fiber for returning the light emission given off by the doped crystal which is presented in the form of a crystal covering covering a determined location on the surface to be scanned, each of said fibers being surrounded by a metal capillary.

Device for optically measuring a cryogenic temperature

The present invention relates to a device for optically measuring the temperatures of cryogenic fluids by analyzing the decay in the luminescence of a doped crystal, the device comprising a light source for exciting said crystal, an optical fiber for transporting the light flux emitted by said source to the crystal and for returning to a detection assembly the luminescent light emitted by the crystal as a result, and a measurement probe past which the fluid moves, wherein the doped crystal is constituted by one of the crystals from the group comprising strontium fluoride doped with divalent ytterbium, SrF.sub.2 :Yb.sup.2+ ; and calcium fluoride doped with divalent ytterbium, CaF.sub.2 :Yb.sup.2+. The crystal is placed at an interior end of a housing constituting the probe. The fiber has a surrounding capillary being placed in the housing facing the covering. A chamber is defined between the end of the fiber and the covering. The housing includes an inlet orifice in the chamber perpendicular to the fiber axis and an outlet for a fluid in the chamber.

Device of optically measuring a cryogenic temperature

A process and a device for the optical measurement of vibrations of rotating turbine blades moving with a specified speed of rotation. In one embodiment, the process comprises the steps of generating three reference signals in response to the detection, by an optical detector, of the passing of a marking made on the hub of a turbine wheel; detecting measurement signals, by another optical detector, in response to the passing of another marking made on at least one of the parts of a turbine blade, the blade undergoing oscillation; determining the time offsets existing between each of the reference signals and each of the measurement signals, these offsets being, in the absence of oscillations of the blade, zero or equal to specified constant values; and calculating the amplitude, frequency and phase components of blade vibration from the various offsets recorded.

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Saint Marcel, France

Jacky Y Rouhet