Method and device for testing water droplet shedding ability of aircraft wing

• US 9,804,061 B2
• Filed: 03/04/2016
• Issued: 10/31/2017
• Est. Priority Date: 03/05/2015
• Status: Active Grant

• Current Assignee: Subaru Corp.
• Original Assignee: Subaru Corp.
• Inventors: Tanaka, Taro
• Primary Examiner(s): Gibson, Randy
• Assistant Examiner(s): Kidanu, Gedeon M
• Application Number:
  US15/061,346
• Publication Number:
  US 20160258843A1
• Time in Patent Office: 606 Days
• Field of Search: 731183, 73147
• CPC Class Codes: B64D 15/00 De-icing or preventing icing on exterior surfaces of aircraft motor vehicles specially adapted for carrying de-icing equipment B60P
• CPC Class Codes: B64D 15/20 Means for detecting icing or initiating de-icing
• CPC Class Codes: G01M 9/02 Wind tunnels
• CPC Class Codes: G01M 9/06 Measuring arrangements specially adapted for aerodynamic testing
• CPC Class Codes: G01M 9/067 visualisation
• CPC Class Codes: G01M 99/00 Subject matter not provided for in other groups of this subclass
• CPC Class Codes: G09B 25/00 Models for purposes not provided for in G09B23/00, e.g. full-sized devices for demonstration purposes model vehicles, tracks therefor, models in the nature of toys A63H

Abstract

A method for testing water droplet shedding ability of a surface of an aircraft wing includes: blowing air toward a surface of a cylindrical member in an airflow direction perpendicular to an axial direction of the cylindrical member, the cylindrical member simulating the wing and having water-related surface characteristics that differ across a predetermined boundary position in a circumferential direction; supplying a water droplet to a portion of the surface of the cylindrical member on a leading edge side with respect to a flow of the air; and capturing an image of the water droplet that moves on the surface of the cylindrical member across the boundary position due to the flow of the air.

Claims

1. A method for testing water droplet shedding ability of a surface of an aircraft wing, the method comprising:

blowing air from a blower toward a surface of a cylindrical member in an airflow direction perpendicular to an axial direction of the cylindrical member, the cylindrical member simulating the wing and having water-related surface characteristics that differ across a predetermined boundary position in a circumferential direction;

supplying a water droplet from an inner side of the cylindrical member to a portion of the surface of the cylindrical member on a leading edge side with respect to a flow of the air; and

capturing an image indicating behavior of the water droplet that moves on the surface of the cylindrical member across the boundary position due to the flow of the air.

2. The method according to claim 1, wherein an ambient temperature of the cylindrical member is room temperature.

3. The method according to claim 1, wherein the method is performed under ambient temperature at 0°

C. or higher.

4. The method according to claim 1, wherein the cylindrical member simulates an aircraft wing that has characteristics that differ between a leading edge side and a trailing edge side across the predetermined boundary position, and

wherein the cylindrical member has a radius that is substantially equal to a radius of curvature of the wing at the boundary position, and a central angle between a line passing through the boundary position of the cylindrical member and the airflow direction is substantially equal to an angle between a line perpendicular to the wing at the boundary position of the wing and a direction of a flow of air.

5. The method according to claim 4, wherein an ambient temperature of the cylindrical member is room temperature.

6. The method according to claim 1, wherein a region of the surface of the cylindrical member on a leading edge side of the boundary position is a non-hydrophobic region and a region of the surface of the cylindrical member on a trailing edge side of the boundary position is a hydrophobic region.

7. The method according to claim 6, wherein an ambient temperature of the cylindrical member is room temperature.

8. The method according to claim 6, wherein the cylindrical member simulates an aircraft wing that has characteristics that differ between a leading edge side and a trailing edge side across the predetermined boundary position, and

wherein the cylindrical member has a radius that is substantially equal to a radius of curvature of the wing at the boundary position, and a central angle between a line passing through the boundary position of the cylindrical member and the airflow direction is substantially equal to an angle between a line perpendicular to the wing at the boundary position of the wing and a direction of a flow of air.

9. The method according to claim 8, wherein an ambient temperature of the cylindrical member is room temperature.

10. A device for testing water droplet shedding ability of a surface of an aircraft wing, the device comprising:

a cylindrical member that simulates the wing and has water-related surface characteristics that differ across a predetermined boundary position in a circumferential direction;

a blower that blows air toward a surface of the cylindrical member in an airflow direction perpendicular to an axial direction of the cylindrical member;

a water droplet supply that supplies a water droplet from an inner side of the cylindrical member to a portion of the surface of the cylindrical member on a leading edge side with respect to a flow of the air; and

an image capturer that captures an image indicating behavior of the water droplet that moves on the surface of the cylindrical member across the boundary position due to the flow of the air.

11. A method for testing water droplet shedding ability of a surface of an aircraft wing, the method comprising:

blowing air toward a surface of a cylindrical member in an airflow direction perpendicular to an axial direction of the cylindrical member, the cylindrical member simulating the wing and having water-related surface characteristics that differ across a predetermined boundary position in a circumferential direction;

supplying a water droplet from an inner side of the cylindrical member to a portion of the surface of the cylindrical member on a leading edge side with respect to a flow of the air; and

capturing an image of the water droplet that moves on the surface of the cylindrical member across the boundary position due to the flow of the air.

12. The method according to claim 11, wherein the cylindrical member simulates an aircraft wing that has characteristics that differ between a leading edge side and a trailing edge side across the predetermined boundary position, and

wherein the cylindrical member has a radius that is substantially equal to a radius of curvature of the wing at the boundary position, and a central angle between a line passing through the boundary position of the cylindrical member and the airflow direction is substantially equal to an angle between a line perpendicular to the wing at the boundary position of the wing and a direction of a flow of air.

13. The method according to claim 11, wherein an ambient temperature of the cylindrical member is room temperature.

14. The method according to claim 11, wherein a region of the surface of the cylindrical member on a leading edge side of the boundary position is a non-hydrophobic region and a region of the surface of the cylindrical member on a trailing edge side of the boundary position is a hydrophobic region.

15. The method according to claim 14, wherein the cylindrical member simulates an aircraft wing that has characteristics that differ between a leading edge side and a trailing edge side across the predetermined boundary position, and

wherein the cylindrical member has a radius that is substantially equal to a radius of curvature of the wing at the boundary position, and a central angle between a line passing through the boundary position of the cylindrical member and the airflow direction is substantially equal to an angle between a line perpendicular to the wing at the boundary position of the wing and a direction of a flow of air.