System and method for measuring tip velocity of sprayed fuel

• US 20060072101A1
• Filed: 10/04/2005
• Published: 04/06/2006
• Est. Priority Date: 10/05/2004
• Status: Active Grant

• Current Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Original Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Inventors: Park, Young-Kug
• Granted Patent: US 7,405,813 B2
• Time in Patent Office: Days
• US Class Current: 356/28
• CPC Class Codes: G01P 5/001 Full-field flow measurement, e.g. determining flow velocity and direction in a whole region at the same time, flow visualisation
• CPC Class Codes: G01P 5/20 using particles entrained by a fluid stream G01P5/22 takes precedence

Abstract

A system and method for measuring tip velocity of sprayed fuel in an engine includes a light source, a lens, a Charge-Coupled Device (CCD) camera, and a control unit. The lens allows light, which is emitted from the light source, to enter into a combustion chamber. The CCD camera photographs the shapes of the dispersion of the sprayed fuel. The control unit causes the light source to emit light two times by controlling the light source, acquiring a single frame image of the shapes of the dispersion of the sprayed fuel by controlling the CCD camera, and calculates the tip velocity of the sprayed fuel by processing the acquired image.

Claims

1. A system for measuring tip velocity of sprayed fuel in an engine, comprising:

a light source;

a lens for allowing light emitted from the light source to enter into a combustion chamber;

a Charge-Coupled Device (CCD) camera configured to provide images of dispersion shapes of the sprayed fuel; and

a control unit controlling the light source to emit light at least two times acquiring a single frame image of the dispersion shape of the sprayed fuel from the CCD camera, and calculating the tip velocity of the sprayed fuel by processing the acquired image.

2. The system as set forth in claim 1, further comprising a pinhole for eliminating a region, in which light is scattered, in front of the CCD camera.

3. The system as set forth in claim 1, wherein the lens is a convex lens located between the light source and the combustion chamber.

4. A method for measuring tip velocity of sprayed fuel in an engine, comprising:

emitting light toward a combustion chamber into which fuel is sprayed;

photographing dispersion shapes of the sprayed fuel during two emissions of light, and acquiring a single frame image of the dispersion shapes of the sprayed fuel from the two emissions of light;

dividing the single frame image into two images based on brightness values, obtaining boundaries between the dispersion shapes of the sprayed fuel and a background from the divided images, and obtaining a movement distance from the obtained boundaries; and

calculating the tip velocity of the sprayed fuel by dividing the movement distance by a time interval between the two light emissions.

5. The method as set forth in claim 4, wherein the step of dividing the single frame image into two images based on the brightness values comprises:

acquiring a first image by setting a brightness value of each pixel to 0 when the brightness value of the pixel is smaller than a first threshold value, and by setting a brightness value of each pixel to 1 when the brightness value of the pixel is equal to or larger than the first threshold; and

acquiring a second image by setting a brightness value of each pixel to 0 when the brightness value of the pixel is smaller than a second threshold value, and by setting a brightness value of each pixel to 1 when the brightness value of the pixel is equal to or larger than the second threshold.

6. The method as set forth in claim 5, wherein the second threshold value is larger than the first threshold value, and is smaller than a brightness value of the background.

7. The method as set forth in claim 5, wherein the step of obtaining the boundaries between the shapes of the dispersion of the sprayed fuel and the background from the divided images determines that a corresponding pixel is located in a boundary region if a value, which is obtained by multiplying a brightness value of an arbitrary pixel by (4-brightness values of 4 pixels adjacent to the arbitrary pixel), is 1.