UV sterilization apparatus, system, and method for aircraft air systems
A sanitizing unit configured for use in an air distribution system of a passenger aircraft is disclosed. The sanitizing unit may include an input structure connected to a cabin air supply plenum, a UV reflective insert that defines an irradiation chamber, at least one ultraviolet (UV) light emitting diode (LED) positioned to provide UV radiation to an airflow within the irradiation chamber, a UV attenuator; and an output structure connected to at least one overhead passenger vent, wherein the at least one overhead passenger vent is configured to output a treated airflow.
1. A sanitizing unit configured for use in an air distribution system of a passenger aircraft, the sanitizing unit comprising:
an input structure configured to connect to a cabin air supply plenum;
a main housing;
a UV reflective insert that defines an irradiation chamber, wherein the UV reflective insert is coaxial with the main housing, and wherein a ratio of a total length of the irradiation chamber to a cross-sectional area of the irradiation chamber is about 6;
at least one ultraviolet (UV) light emitting diode (LED) positioned to provide UV radiation to an airflow within the irradiation chamber;
a UV attenuator; and
an output structure connected to at least one overhead passenger vent, wherein the at least one overhead passenger vent comprises a plurality of air discharge grilles, wherein:
each air discharge grille has a perimeter set of holes having a first size, and a center set of holes having a second size larger than the first size; and
each air discharge grille is configured to output a contoured flow of treated air.
2. The sanitizing unit of claim 1 , wherein each of the plurality of air discharge grilles is configured such that the contoured flow of treated air is uniformly distributed to a plurality of passenger seats within a row in the aircraft.
3. The sanitizing unit of claim 1 , wherein the at least one UV LED comprises a plurality of LEDs emitting light at a wavelength of about 265 nm.
4. The sanitizing unit of claim 1 , wherein the UV reflective insert comprises a surface coating of polished aluminum.
5. The sanitizing unit of claim 1 , wherein a diameter of the irradiation chamber is based on a layout of passenger seats within the aircraft, and the dimensions of the passenger seats.
6. The sanitizing unit of claim 1 , wherein the UV attenuator comprises a plurality of overlapping concentric conical frustum stacked using support fins, wherein each conical frustum comprises:
at least one exterior surface coated with a UV reflective material; and
at least one interior surface coated with a UV radiation-absorbing material.
7. The sanitizing unit of claim 1 , wherein the UV attenuator comprises:
at least one central cone having a concave outer surface, wherein the concave outer surface is coated with a UV reflective material;
a plurality of support fins; and
an outer cylinder;
wherein interior surfaces of the central cone and the outer cylinder are coated with a UV radiation-absorbing material.
8. An air distribution system installed in a passenger aircraft, the system comprising:
a plurality of sanitizing units, wherein each sanitizing unit comprises:
an input structure configured to connect to a cabin air supply plenum;
a main housing;
a UV reflective insert that defines an irradiation chamber, wherein the UV reflective insert is coaxial with the main housing, and wherein a ratio of a total length of the irradiation chamber to a cross-sectional area of the irradiation chamber is about 6;
at least one ultraviolet (UV) light emitting diode (LED) positioned to provide UV radiation to an airflow within the irradiation chamber;
a UV attenuator; and
an output structure; and
a plurality of air distribution grilles each configured to output a contoured flow of treated air to the aircraft cabin, wherein:
the output structure of each sanitizing chamber is connected to at least one of the plurality of air distribution grilles; and
each of the plurality of air distribution grilles has a perimeter set of holes having a first size, and a center set of holes having a second size larger than the first size.
9. The air distribution system of claim 8 , wherein the output structure of each sanitizing chamber is connected to two air distribution grilles.
10. An air circulation system in a passenger aircraft, the system comprising:
at least one circulation fan;
at least one HEPA filter;
an air distribution system, comprising:
a plurality of sanitizing units, wherein each sanitizing unit comprises:
an input structure configured to connect to a cabin air supply plenum;
a main housing;
a UV reflective insert that defines an irradiation chamber, wherein the UV reflective insert is coaxial with the main housing, and wherein a ratio of a total length of the irradiation chamber to a cross-sectional area of the irradiation chamber is about 6;
at least one ultraviolet (UV) light emitting diode (LED) positioned to provide UV radiation to an airflow within the irradiation chamber;
a UV attenuator; and
an output structure; and
a plurality of air distribution grilles configured to output a contoured flow of treated air to the aircraft cabin, wherein:
the output structure of each sanitizing chamber is connected to at least one of the plurality of air distribution grilles; and
each of the plurality of air discharge grilles has a perimeter set of holes having a first size, and a center set of holes having a second size larger than the first size; and
an air conditioner comprising at least one mixing unit configured to provide recirculated air to the air distribution system.