Aircraft equipment cooling
An aircraft includes: a cockpit, the inside of which is pressurized; equipment which is at least partially disposed on the outside of the cockpit (external space) where the pressure is lower than the inside of the cockpit (internal space); a forced air delivery mechanism which discharges air from a peripheral space of the equipment on the outside of the cockpit by an exhaust fan to supply a branch flow divided from a main flow of air-conditioning exhaust, which has air-conditioned the inside of the cockpit, as cooling air to the equipment; and a natural air delivery mechanism which uses a differential pressure between the inside of the cockpit and the outside of the cockpit to supply air inside the cockpit as cooling air to the equipment through a ventilation opening putting in communication the peripheral space and the inside of the cockpit with one another.
1. An aircraft comprising:
a cockpit, the inside of which is pressurized;
equipment which is at least partially disposed on the outside of the cockpit where the pressure is lower than the inside of the cockpit;
a forced air delivery mechanism which discharges air from a peripheral space of the equipment on the outside of the cockpit by an exhaust fan in order to supply a branch flow divided from a main flow of air-conditioning exhaust, which has air-conditioned the inside of the cockpit, as cooling air to the equipment; and
a natural air delivery mechanism which uses a differential pressure between the inside of the cockpit and the outside of the cockpit to supply air inside the cockpit as cooling air to the equipment through a ventilation opening putting in communication the peripheral space and the inside of the cockpit with one another.
2. The aircraft according to claim 1 , wherein, even if the forced air delivery mechanism malfunctions, air is delivered to the equipment by the natural air delivery mechanism.
3. The aircraft according to claim 1 , further comprising a flow passage which connects the main flow and the peripheral space with each other, wherein, when the exhaust fan is operating, the branch flow divided from the main flow flows through the flow passage and, when the exhaust fan is down, air in the peripheral space flows through the flow passage toward the main flow.
4. The aircraft according to claim 1 , wherein
the main flow flows toward an underfloor space which is on the outside of the cockpit, and
the branch flow flows via the peripheral space into the underfloor space where the exhaust fan is located.
5. The aircraft according to claim 1 , wherein the ventilation opening is located at a level lower than half the height of the inside of the cockpit.
6. The aircraft according to claim 1 , wherein the ventilation opening is formed in a wall which separates between the inside of the cockpit and the peripheral space.
7. The aircraft according to claim 6 , wherein:
the wall includes an upright part rising from the front end of a floor and a backward part extending backward from the upper end of the upright part, the floor defining the inside of the cockpit together with the wall; and
the ventilation hole penetrates the backward part in the thickness direction.
8. The aircraft according to claim 1 , wherein the equipment includes a cooling fan which discharges heat of the equipment to the peripheral space.
9. The aircraft according to claim 8 , wherein the ventilation opening is located in the vicinity of a suction opening of the equipment through which air is suctioned from the peripheral space by the cooling fan.
10. The aircraft according to claim 1 , wherein the equipment is a display device which displays information required for flight of the aircraft.