Air diffuser and construction method thereof

1 . An air diffuser, comprising:

an open upper end part, the open upper end part comprising an upper wall and an air supply inlet in the upper wall for connecting with an air supply pipe;

an open lower end part; and

an air flow passage defined between the open upper end part and the open lower end part, the air flow passage comprising a first side wall and a second side wall which are connected between the open upper end part and the open lower end part, and are symmetrically located with respect to a vertical center plane of the air diffuser;

wherein the section outline of each of the first side wall and the second side wall has a curved shape bending inwards, such that in a direction from the open upper end part to the open lower end part, the air flow passage has, in sequence, a contraction portion bending toward the vertical center plane and an expansion portion away from the vertical center plane, and wherein a maximum width of the air inlet in the upper wall is less than a minimum width of the air flow passage between the first side wall and the second side wall.

2 . The air diffuser as claimed in claim 1 , wherein the curved shape comprises a first arc-shaped part and a second arc-shaped part connected in sequence in the direction from the open upper end part to the open lower end part.

3 . The air diffuser as claimed in claim 2 , wherein at least a portion of the first arc-shaped part is curved towards the vertical center plane, a first end of the first arc-shaped part is connected to the open upper end part, and the width of the air flow passage at at least a part of the first arc-shaped part is less than or equal to the width of the open upper end part between the first side wall and the second side wall.

4 . The air diffuser as claimed in claim 3 , wherein at least a portion of the second arc-shaped part is curved away from the vertical center plane, a first end of the second arc-shaped part is connected to a second end of the first arc-shaped part, and a second end of the second arc-shaped part is connected to the open lower end part.

5 . The air diffuser as claimed in claim 4 , wherein the first arc-shaped part is formed such that the radius of curvature of the first arc-shaped part is less than the radius of curvature of the second arc-shaped part.

6 . The air diffuser as claimed in claim 4 , wherein the first arc-shaped part is formed such that the distance from the first end of the first arc-shaped part to the vertical center plane is identical to the distance from the second end of the first arc-shaped part to the vertical center plane.

7 . The air diffuser as claimed in claim 4 , wherein the second arc-shaped part is formed such that the second arc-shaped part at its second end is tangent to the plane in which the second arc-shaped part contacts and connects with the open lower end part.

8 . The air diffuser as claimed in claim 4 , wherein a connection point is formed where the second end of the first arc-shaped part being connected to the first end of the second arc-shaped part, wherein an included angle formed by the tangent line to the first arc-shaped part at the connection point and the tangent line to the second arc-shaped part at the connection point is less than or equal to 20 degrees.

9 . The air diffuser as claimed in claim 1 , wherein the width of the open lower end part between the first side wall and the second side wall is greater than the width of the open upper end part between the first side wall and the second side wall.

10 . The air diffuser as claimed in claim 9 , wherein the ratio of the width of the open lower end part and the width of the open upper end part is about 2:1.

11 . The air diffuser as claimed in claim 1 , wherein the air diffuser has an average air supply speed ranging from 3 m/s to 4 m/s at the open lower end part.

12 . The air diffuser as claimed in claim 11 , wherein the air diffuser has an average air supply angle ranging from 30 degrees to 40 degrees at the open lower end part.

13 . The air diffuser as claimed in claim 1 , wherein the air diffuser further comprises a front wall and a rear wall which are parallel to each other and parallel to the direction from the open upper end part to the open lower end part.

14 . The air diffuser as claimed in claim 1 , wherein the air diffuser is used on a transportation vehicle.

15 . The air diffuser as claimed in claim 14 , wherein the transportation vehicle is an aircraft, and the air diffuser is mounted within a cabin of the aircraft.

16 . A method for construction of the air diffuser of claim 1 , comprising:

providing the open upper end part and the open lower end part of the air diffuser; and

configuring the first side wall and the second side wall which are connected between the open upper end part and the open lower end part and symmetrically located with respect to the vertical center plane of the air diffuser, the first side wall and the second side wall define the air flow passage between the open upper end part and the open lower end part;

wherein configuring the first side wall and the second side wall comprises:

forming the section outline of each of the first side wall and the second side wall into the curved shape bending inwards, such that in the direction from the open upper end part to the open lower end part, the air flow passage has, in sequence, the contraction portion bending towards the vertical center plane and the expansion portion away from the vertical center plane.

17 . The air diffuser as claimed in claim 1 , wherein a distance between the first side wall and the second side wall at the top of the open upper end part is greater than a distance between the first side wall and the second side wall at the bottom of the open upper end part.

18 . An aircraft comprising:

a cabin defined by a cabin side wall and a luggage compartment arranged above the side wall;

an air diffuser located between the cabin side wall and the luggage compartment, the air diffuser having an upper end and a lower end and being in fluid communication with an interior space of the cabin at the lower end; and

an air supply pipe connected to the upper end of the air diffuser and configured to deliver conditioned air into the air diffuser,

wherein the air diffuser defines an air-flow passage extending from the upper end to the lower end, the air-flow passage including opposing diffuser side walls connected between the upper and lower ends,

wherein each of the diffuser side walls has a curved shape bending inward such that, in a direction from the upper end to the lower end, the air-flow passage includes, in sequence, a contraction portion bending toward a vertical center plane of the air diffuser and an expansion portion bending away from the vertical center plane, and

wherein the upper end of the air diffuser comprises an upper wall having an air inlet for connection with the air supply pipe, and wherein a maximum width of the air inlet is less than a minimum width of the air-flow passage between the diffuser side walls.

19 . The aircraft of claim 18 , wherein the air diffuser is free of an orifice plate and a grid structure at the lower end.

20 . The aircraft of claim 18 , wherein the air diffuser further comprises a front wall and a rear wall which are parallel to each other.