Patent ID: 7969165
Filing Date: 2011-06-28
Classification: G01B

Abstract:
1. A device for determining a distance between a rotor blade and a wall of a turbine engine surrounding the rotor blade, comprising: a waveguide that guides and emits electromagnetic waves in a direction to the rotor blade through a waveguide opening facing the rotor blade; a sealing element arranged in the waveguide that reflects a first portion of the electromagnetic waves having a first frequency and transmits through a second portion of the electromagnetic waves having a second frequency to the rotor blade; a first unit that injects the electromagnetic waves into the waveguide; a second unit that receives reflected portions of the electromagnetic waves comprising a first reflected portion of the electromagnetic waves reflected by the sealing element and a second reflected portion of the electromagnetic waves reflected by the rotor blade; and an evaluation unit that compares phases of the electromagnetic waves to be injected with phases of the reflected portions of the electromagnetic waves for each frequency and determines the distance based on the phase comparison.