Method for automatic calculation of axial cooling fan shroud circular opening size

1. A computer-implemented method for determining shroud size of an axial fan, the method comprises:

receiving by a computer processing system digital data of a three-dimensional representation of a shroud and an axial fan;

partitioning by the computer processing system, the received digital data into a first partition corresponding to a shroud segment and a second partition corresponding to an axial fan segment;

determining by the computer processing system, a shroud boundary ring for the shroud segment;

applying by the computing processing system to an image of the first partition, a series of beams to determine in pixels a shroud diameter of the shroud;

determining by the computing processing system pixels in the image that have values that produce a signal indicating that the pixels are coincident with portions of the shroud; and

calculating by the computer processing system, the shroud diameter from information from the series of beams, including beam angles and length of travel of the series of beams when the signal is detected.

2. The method of claim 1 , further comprising:

determining a viewing angle of the shroud boundary ring.

3. The method of claim 1 , further comprising:

repeating applying the beams and determining until the signal is detected.

4. The method of claim 1 , wherein calculating the shroud diameter further comprises:

determining from the digital data of the three-dimensional representation of the axial fan, a two-dimensional projection of the shroud to determine the shroud boundary ring.

5. The method of claim 4 wherein the calculated shroud diameter is determined in pixels using digital image of the feature lines of the fan so that a conversion ratio between physical units and pixel is obtained.

6. The method of claim 4 further comprising:

calculating a value corresponding to the center of the fan using the fan image; and

passing the calculated center value to the determining the signal.

7. The method of claim 4 wherein a viewing vector, a depth of the field of view, and the image resolution are based on the fan diameter so that the dimensions of the fan and the shroud do not affect measurement accuracy.

8. The method of claim 4 wherein the applying the beams emits plural beams from the fan edges in plural directions to search for the shroud inner circle to reduce the computational cost and increase the signal-to-noise ratio when multiple concentric circles are present.

9. The method of claim 4 further comprises:

excluding certain directions; and

applying high-pass filtering to the determined signal to improve measurement accuracies for structures present along the opening or when the shroud opening is less circular after discretization.

10. The method of claim 4 further comprising:

searching for target pixels along the beam moving direction and among neighboring pixels.

11. A computer system comprising:

one or more processors;

memory operatively coupled to the one or more processors, and

computer storage storing a computer program for determining shroud size of an axial fan that comprises instructions to cause the computer system to:

receive digital data of a three-dimensional representation of a shroud and an axial fan;

partition the received digital data into a first partition corresponding to a shroud segment and a second partition corresponding to an axial fan segment,

determine a shroud boundary ring for the shroud segment;

apply to an image of the first partition a series of beams to determine in pixels a shroud diameter of the shroud;

determine pixels in the image that have values that produce a signal indicating that the pixels are coincident with portions of the shroud; and

calculate the shroud diameter from information from the series of beams, including beam angles and length of travel of the series of beams when the signal is detected.

12. The system of claim 11 , further comprising instructions to:

determine a viewing angle of the shroud boundary ring; and

repeat instructions to apply the beams; and instructions to determine until the signal is detected.

13. The system of claim 11 , further comprising instructions to:

determine from the digital data of the three-dimensional representation of the axial fan, a two-dimensional projection of the shroud to determine the shroud boundary ring.

14. The system of claim 11 , wherein the calculated shroud diameter is determined in pixels using digital image of the feature lines of the fan so that a conversion ratio between physical units and pixel is obtained.

15. A computer program product stored on an non-transitory computer readable medium for determining shroud size of an axial fan, the computer program product including instructions for causing a system comprising one or more processors and memory to:

receive digital data of a three-dimensional representation of a shroud and an axial fan;

partition the received digital data into a first partition corresponding to a shroud segment and a second partition corresponding to an axial fan segment,

determine a shroud boundary ring for the shroud segment;

apply to an image of the first partition, a series of beams to determine in pixels a shroud diameter of the shroud;

determine pixels in the image that have values that produce a signal indicating that the pixels are coincident with portions of the shroud; and

calculate the shroud diameter from information from the series of beams, including beam angles and length of travel of the series of beams when the signal is detected.

16. The product of claim 15 , further comprising instructions to:

determine a viewing angle of the shroud boundary ring; and

repeat instructions to apply the beams; and instructions to determine until the signal is detected.

17. The product of claim 15 wherein instructions to calculate the shroud diameter further comprises instructions to:

determine from the digital data of three-dimensional representation of the axial fan, a two-dimensional projection of the shroud to determine the shroud boundary ring.

18. The product of claim 17 wherein the calculated shroud diameter is determined in pixels using digital image of the feature lines of the fan so that a conversion ratio between physical units and pixel is obtained.