Air distribution system for use in an aircraft

An aircraft including a fuselage having a side wall at least partially defining a passenger cabin and a crown section of the aircraft. The passenger cabin includes an overhead zone, a passenger zone, and a floor zone. An air supply duct is positioned within the crown section, and the air supply duct is configured to pressurize the crown section with air. At least one return air outlet is defined in the floor zone. An interior structure is coupled to the side wall and extends between the passenger cabin and the crown section. The interior structure includes a plurality of nozzles oriented to discharge the pressurized air from the crown section along an airflow path that extends downward through the overhead zone, downward through the passenger zone, and then towards the at least one return air outlet.

FIELD

The field relates generally to environmental control systems for use in confined spaces designed for human occupancy and, more specifically, to air distribution systems that facilitate minimizing airflow between passengers within confined spaces, such as aircraft passenger cabins.

BACKGROUND

Some known pressurized aircraft use Environmental Control Systems (“ECS”) to maintain cabin pressurization and to control cabin temperatures during flight. The ECS generally channels external air from the engines towards the aircraft cabin to pressurize the cabin. Some known systems condition the air using air conditioning packs, and the conditioned air is distributed within the cabin via an air distribution system. Some air distribution systems include multiple discrete nozzles located on either side of the interior of the aircraft fuselage above the passengers. The nozzles discharge conditioned air therefrom to generate two opposing and counter-rotating “cells” of air that circulate across the passenger seats before exiting the cabin through a return air grille located at the floor of the cabin. However, generating the counter-rotating cells requires the air to be discharged at relatively high velocities, which can generate undesirable noise pollution within the cabin. In addition, the counter-rotating cells may cause cross-circulation to occur between passengers, which is a significant consideration in view of recent global health crises.

BRIEF DESCRIPTION

One aspect is an aircraft including a side wall at least partially defining a passenger cabin and a crown section of the aircraft. The passenger cabin includes an overhead zone, a passenger zone, and a floor zone. An air supply duct is positioned within the crown section, and the air supply duct is configured to pressurize the crown section with air. At least one return air outlet is defined in the floor zone. An interior structure is coupled to the side wall and extends between the passenger cabin and the crown section. The interior structure includes a plurality of nozzles oriented to discharge the pressurized air from the crown section along an airflow path that extends downward through the overhead zone, downward through the passenger zone, and then towards the at least one return air outlet.

Another aspect is an aircraft including a side wall at least partially defining a passenger cabin and a crown section of the aircraft. The passenger cabin includes an overhead zone, a passenger zone, and a floor zone. An air supply duct is positioned within the crown section, and the air supply duct is configured to channel air therethrough. At least one return air outlet is defined in the floor zone. A plurality of interior panels extend between the passenger cabin and the crown section, and each interior panel is coupled in flow communication with the air supply duct. The plurality of interior panels each include a plurality of perforations configured to discharge the air therefrom along an airflow path that extends downward through the overhead zone, downward through the passenger zone, and then towards the at least one return air outlet.

Yet another aspect is an air distribution system including an air supply duct configured to channel air therethrough. A plurality of interior panels are each coupled in flow communication with the air supply duct, and the plurality of interior panels are coupled to each other in an array to define an interior structure. Each interior panel includes a housing having a side wall defining an air inlet and an air outlet. A porous support structure is coupled to the side wall at the air outlet. An air plenum is defined between the air inlet and a first side of the porous support structure, and a plurality of perforations configured to discharge the air therefrom are defined on a second side of the porous support structure.

DETAILED DESCRIPTION

Examples described below include air distribution systems that facilitate minimizing airflow between passengers within confined spaces, such as aircraft passenger cabins. Example systems described provide a displacement ventilation scheme that generates bulk downward airflow within the confined space. In one example, the bulk downward airflow is discharged from above seated passengers in the confined space, downward past the passengers, and towards an outlet located at the floor of the confined space. This directional bulk downward airflow facilitates limiting cross-circulation between passengers seated next to each other in a respective row of an aircraft, for example. Example systems facilitate reducing the spread of airborne contaminants between nearby occupants, reducing noise and undesirable drafts, and limiting the formation of stagnant zones of circulation within the confined space.

FIG.1is a cross-sectional view of an aircraft100having an example air distribution system102therein. Aircraft100includes a fuselage104having a side wall106that at least partially defines a passenger cabin108and a crown section110of aircraft100. Crown section110is positioned above passenger cabin108, and an interior structure112coupled to side wall106extends between crown section110and passenger cabin108. Passenger cabin108includes an overhead zone114, a passenger zone116, and a floor zone118. Passenger zone116includes a plurality of seats120designed for human occupancy. Seats120are arranged in one or more rows122across passenger cabin108. Overhead zone114is located above passenger seats120, and floor zone118is located below passenger seats120.

Air distribution system102includes an air supply duct124positioned within crown section110. In one example, interior structure112is arranged such that crown section110defines an open volume between side wall106and interior structure112. Air supply duct124is configured to channel conditioned air126therethrough, which is received from an environment control system (not shown) of aircraft100. Air supply duct124is configured to discharge the conditioned air126within the crown section110to pressurize crown section110with conditioned air126. Pressurizing crown section110with conditioned air126facilitates supplying passenger cabin108with conditioned air126. For example, at least one return air outlet128is defined in floor zone118and, as will be described in more detail below, conditioned air126discharged from crown section110is channeled through passenger cabin108and then exhausted from passenger cabin108through return air outlet128. Referring toFIG.1, return air outlet128is a return air grille defined in side wall106of fuselage. Alternatively, an air exhaust port may be defined in a floor130of passenger cabin108.

Referring toFIG.1, air supply duct124includes a side wall132having a plurality of airflow openings134defined therein. Airflow openings134provide flow communication from air supply duct124to crown section110to facilitate pressurization thereof. Airflow openings134may be any size and/or shape that enables air distribution system102to function as described herein. For example, airflow openings134may be defined by multiple discrete holes or cutouts within side wall106spaced along a length of air supply duct124and fuselage104. In an alternative example, air supply duct124is a piccolo type supply duct.

Interior structure112is formed from a plurality of components, such as interior panels136, stowage bins138, overhead consoles140, and the like. In one example, at least some of components are spaced from each other to define gaps142therebetween. For example, interior panels136, stowage bins138, and overhead consoles140may be coupled to each other, but also spaced from each other to provide airflow communication between crown section110and passenger cabin108through gaps142. In such an example, a blocking member144may extend across at least one of the plurality of gaps142. Blocking member144is adapted to restrict visibility into crown section110from passenger cabin108while still permitting airflow communication therebetween. Components, such as overhead consoles140, may also be spaced from side wall106to define additional gaps142.

Accordingly, gaps142define a plurality of nozzles146within interior structure112. In an alternative example, the components themselves include airflow openings (not shown) defined therein to define nozzles146of interior structure112. For example, gaps may be hidden behind light valences or other interior features to define additional nozzles146within interior structure112. Nozzles146are designed to discharge conditioned air126therefrom in a substantially downward direction relative to crown section110. Referring toFIG.1, conditioned air126travels along an airflow path148that extends downward through overhead zone114, downward through passenger zone116, and then towards return air outlet128located in floor zone118. As a result of a combination of factors, such as airflow discharge velocity, discharge directionality of conditioned air126, and/or a pressure differential defined at return air outlet128, for example, airflow path148extends downward through passenger cabin108to facilitate limiting cross-circulation between passengers seated next to each other in a respective row122of aircraft100. As used herein, “downward” refers to a one-way direction of travel that reduces in height between two points, such as from nozzles146to return air outlet128, without the direction of travel increasing in height between the two points.

FIG.2is a cross-sectional view of aircraft100having an alternative air distribution system150therein. In the illustrated example, interior structure112includes a plurality of interior panels136extending between crown section110and passenger cabin108. Interior panels136may be ceiling panels, side wall panels, overhead console panels, and the like, which are designed to be visible and aesthetically pleasing to the occupants of passenger cabin108. Each interior panel136is coupled in flow communication with air supply duct124. For example, a branched duct152may be coupled between air supply duct124and each interior panel136to enable conditioned air126to be channeled from air supply duct124to the plurality of interior panels136. As will be described in more detail below, each interior panel136includes a plurality of perforations154(shown inFIG.3) configured to discharge conditioned air126therefrom in a substantially downward direction relative to crown section110.

As illustrated inFIG.2, conditioned air126travels along an airflow path156that extends downward through overhead zone114, downward through passenger zone116, and then towards return air outlet128located in floor zone118. Similar to airflow path148, airflow path156extends downward through passenger cabin108to facilitate limiting cross-circulation between passengers seated next to each other in a respective row122of aircraft100.

FIG.3is a cross-sectional view of an example interior panel158that may be used in air distribution system150(shown inFIG.2). In the illustrated example, each interior panel158includes a housing160having a side wall162defining an air inlet164and an air outlet166. Air inlet164is coupled in flow communication with branched duct152(shown inFIG.2) to enable conditioned air126to be channeled therethrough. Conditioned air126is channeled through housing160and then discharged from air outlet166directly into passenger cabin108(shown inFIG.2).

Interior panel158includes a nozzle168coupled to side wall132at air outlet166. In the illustrated example, nozzle168includes a porous support structure170, and at least one layer of material coupled thereto, as will be described in more detail below. Porous support structure170may be any flexible, semi-rigid, or rigid structure that enables airflow to be channeled therethrough. In the illustrated example, porous support structure170is in the form of a honeycomb structure having a plurality of hollow channels extending therethrough. Alternatively, as shown inFIG.4, an interior panel171includes porous support structure170that is in the form of a porous foam material, such as polyvinyl chloride, polyetherimide, polyvinylidene fluoride, and the like.

Nozzle168has a first side172and a second side174. Nozzle168extends across the entirety of air outlet166to define an air plenum176between air inlet164and first side172of nozzle168. Perforations154are defined on second side174of nozzle168. Extending nozzle168across air outlet166facilitates at least partially sealing housing160, which enables air plenum176to be pressurized with conditioned air126channeled through air inlet164. Accordingly, conditioned air126may be distributed across the entire surface area of first side172. In one example, air inlet164is smaller in cross-sectional size than air outlet166. Accordingly, side wall162of housing160may be tapered to increase in cross-sectional size from air inlet164to air outlet166, which facilitates equalizing the pressure of conditioned air126across first side172of nozzle168.

Referring again toFIG.3, nozzle168further includes a layer178of porous material coupled on at least one of first side172or second side174thereof. The porous material may be any material that enables interior panel158to function as described herein. For example, the porous material may be a woven fibrous material, such as in a Leno weave pattern. The woven fibrous material may also be pre-impregnated with resin, adhesive, and the like (i.e., a “prepreg” composite). Accordingly, layer178extends across first side172and/or second side174to provide support to, and increase the rigidity of, porous support structure170while still permitting airflow therethrough.

In the illustrated example, nozzle168also includes a layer180of decorative porous material coupled over layer178of porous material on second side174. Accordingly, layer180defines the exterior surface of interior panel158that is visible to occupants of passenger cabin108(shown inFIG.2). Layer180provides an improved aesthetic appearance, relative to layer178, that is suitable for visibility to occupants of passenger cabin108. The decorative porous material may be any material that enables interior panel158to function as described herein. For example, layer180may be a thermoplastic sheet perforated by laser, chemical etching, abrasive blasting, contact with a drum roller with pins, or other suitable methods. Layer180may also be a cloth fabric material. Accordingly, interior panel158is provided with a plurality of perforations154on second side174thereof. In one example, perforations154are distributed generally substantially uniformly across layer180such that conditioned air126discharged therefrom is in the form of distributed bulk airflow. Thus, airflow is provided across the exposed surface area of layer180.

In operation, conditioned air126is discharged from nozzles146and168at a flow rate greater than a first threshold, and at a velocity less than a second threshold, in order to satisfy a desired airflow recirculation rate through passenger cabin108. The flow rate threshold is based at least partially on the number of occupants aircraft100is designed to transport. Accordingly, in one example, air distribution systems102and150are operable to discharge conditioned air from nozzles146and168at a flow rate greater than about 0.25 pounds per minute per occupant (lbs/min/occupant), greater than about 0.4 lbs/min/occupant, greater than about 0.5 lbs/min/occupant, or greater than about 0.55 lbs/min/occupant. The velocity threshold is based at least partially on a perceived comfort level of occupants of passenger cabin108. Accordingly, in operation, air distribution systems102and150are operable to discharge conditioned air126from nozzles146and168into passenger cabin108at a velocity that is less than a threshold in which occupants of passenger cabin108may perceive an undesirable draft at their seat120. Accordingly, air distribution systems102and150discharge conditioned air126at a velocity of less than about 500 feet per minute (ft/min), less than about 250 ft/min, less than about 100 ft/min, or less than about 50 ft/min.

The systems and methods described are not limited to the specific embodiments described herein, but rather, components of the systems and/or steps of the methods may be utilized independently and separately from other components and/or steps described herein.

This written description uses examples to disclose various implementations, including the best mode, and also to enable any person skilled in the art to practice the various implementations, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the disclosure is defined by the claims, and may include other examples that occur to those skilled in the art after reading this specification. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.