System for detecting, quantifying and/or locating water in aircraft sandwich structures and methods for using this system
View Patent ↗A system for the detection of water in a sandwich structure for aircraft including: a microwave generator, at least two microwaves emitters/sensors mounted in the structure, and a microwave detector capable of detecting the microwaves after propagation in the structure; a data-processing unit associated with a library containing at least one model of the structure when empty. Also methods for implementing this system as well as an aircraft including such a system.
1. A system for the detection of water in a sandwich structure for aircraft, comprising:
a microwave generator,
at least two microwaves emitters/sensors mounted in the structure, and
a microwave detector capable of detecting the microwaves after propagation in the structure; and
a data-processing unit associated with a library containing at least one model of the structure when empty.
2. The system of detection according to claim 1 , wherein each emitter/sensor has a base fixed to the structure and a conductive rod situated within the structure.
3. The system of detection according to claim 1 , wherein the generator generates microwaves that are frequency-modulated about a centre frequency chosen as a function of the structure.
4. The system of detection according to claim 3 , wherein the microwaves are modulated on a frequency interval of the order of 1 GHz about an excitation frequency of water.
5. The system of detection according to claim 1 , wherein the system has at least three emitters/sensors distributed in the structure to locate water by triangulation.
6. The system of detection according to claim 5 , wherein the generator generates pulses.
7. The system according to claim 1 , wherein:
the microwave emitters/sensors are embedded in the structure,
the microwave generator, the microwave detector, the data-processing unit and the library are on the ground.
8. The system of detection according to claim 1 , wherein sandwich structure comprises two skins made of a material impervious to microwaves and an intermediate zone made of a low-microwave-absorbent material.
9. The system of detection according to claim 8 , wherein the skins are made of carbon and the intermediate zone is made of a honeycomb material, Nomex® or glass fiber or a low-microwave-absorbent material such as certain synthetic foam materials.
10. A method for the detection of water in an aircraft sandwich structure, comprising:
an emission of microwaves in the sandwich structure,
a reception of these microwaves by sensors after propagation in the structure, and
a processing of these propagation times to deduce a location of the water therefrom.
11. The method for the detection of water according to claim 10 , wherein the processing comprises a sequential scan at variable frequency to determine the presence of water as well as a volume of this water.
12. The method for the detection of water according to claim 10 , wherein the processing comprises:
a determining of the propagation times of these microwaves in the structure, and
a processing of these propagation times to deduce a location of the water therefrom.
13. The method according to claim 12 wherein that the microwaves are emitted at a fixed frequency.
14. An aircraft comprising:
a sandwich structure; and
a system for the detection of water in a sandwich structure for aircraft, including:
a microwave generator,
at least two microwaves emitters/sensors mounted in the structure, and
a microwave detector capable of detecting the microwaves after propagation in the structure; and
a data-processing unit associated with a library containing at least one model of the structure when empty.