Pipe structure, aircraft, and method for giving robustness to leak detection

1. A pipe structure comprising:

a pipe that is disposed along an approximately horizontal direction, and has a plurality of ducts through which a gaseous body having a higher temperature than a temperature of a surrounding atmosphere continuously flows, and a plurality of couplings each connecting the ducts together; and

a cover that covers an outer periphery of the pipe,

wherein the cover defines a plurality of vents from which the gaseous body leaking from the pipe flows out of the cover at an interval in a length direction of the pipe, and

as the plurality of vents, the cover comprises first vents that are located corresponding to the plurality of couplings, and second vents that are located corresponding to the plurality of ducts,

wherein respective positions of the first vents are substantially set within a range from a two o'clock position to a ten o'clock position through a six o'clock position in a cross sectional surface of the cover, and wherein respective positions of the second vents are substantially set to a twelve o'clock position in the cross sectional surface of the cover.

2. The pipe structure according to claim 1 ,

further comprising a leak sensor that detects a leak of the gaseous body,

wherein the leak sensor has

a sensitive section that passes a position corresponding to each of the plurality of vents and is sensitive to a temperature or a concentration of a gaseous body outside the cover, and

a detection section that detects the leak by using a state of the sensitive section.

3. The pipe structure according to claim 2 ,

wherein

the leak sensor is disposed so as to be erected up along a circumferential direction of the cover at positions corresponding to the second vents.

4. The pipe structure according to claim 2 ,

further comprising a roof that is located in a vicinity of at least one of the first vents,

the roof is configured to restrict a rise of a gaseous body wherein the roof is disposed above the at least one first vent at an interval from the cover that defines the first vents, and

the sensitive section is disposed below the roof.

5. The pipe structure according to claim 4 ,

wherein the roof is supported on the cover by a support portion that links the roof and the cover.

6. The pipe structure according to claim 4 ,

wherein the roof is supported on the sensitive section by a clip that holds the sensitive section.

7. The pipe structure according to claim 2 , the sensitive section of the leak sensor being sensitive to the temperature of the gaseous body outside the cover, and a set temperature of the sensitive section is set between a first range of temperatures of a leak flow rate that is affected by a buoyancy and a second range of temperatures of the leak flow rate that escapes from the influence of the buoyancy.

8. The pipe structure according to claim 1 ,

further comprising a wind protection wall that is located in a vicinity of at least one of the first vents,

the wind protection wall is configured to block a flow of a gaseous body outside the cover that affects a flow of the gaseous body flowing out from the at least one first vent.

9. The pipe structure according to claim 1 ,

wherein the respective positions of the first vents are substantially set within a range from a three o'clock position to a nine o'clock position through a six o'clock position in the cross sectional surface of the cover.

10. The pipe structure according to claim 1 ,

wherein the respective positions of the first vents are substantially set to a three o'clock position or a nine o'clock position in the cross sectional surface of the cover.

11. An aircraft comprising the pipe structure according to claim 1 .

12. The aircraft according to claim 11 ,

wherein the gaseous body is bleed air from an engine or an auxiliary power unit that is a power source of the aircraft.

13. A method for giving robustness to leak detection, comprising:

defining a plurality of vents in a cover that covers an outer periphery of a pipe disposed along an approximately horizontal direction at an interval in a length direction of the pipe, wherein the pipe comprises a plurality of ducts and a plurality of couples, each coupling connecting the ducts together;

causing a gaseous body leaking from the pipe and having a higher temperature than a temperature of an atmosphere around the pipe to flow out of the cover from the vents; and

detecting a leak of the gaseous body by using a temperature or a concentration of the gaseous body at positions corresponding to the vents,

wherein the plurality of vents comprises first vents and second vents,

wherein the first vents are located corresponding to the plurality of couplings, wherein respective positions of the first vents are substantially set within a range from a two o'clock position to a ten o'clock position through a six o'clock position in a cross sectional surface of the cover, and

wherein the second vents are located corresponding to the plurality of ducts, wherein respective positions of the second vents are substantially set to a twelve o'clock position in the cross sectional surface of the cover.

14. The method for giving robustness to leak detection according to claim 13 ,

wherein the pipe is mounted on an aircraft, and

the gaseous body is bleed air from an engine or an auxiliary power unit that is a power source of the aircraft.