US-12625101-B2 - Method for identifying a state of a stream of refrigerant

Abstract

A method for identifying a state of a stream of refrigerant includes capturing a plurality of sample images of a sensor for sensing the stream of the refrigerant, processing each of the plurality of sample images to identify a first color indicative of a dry refrigerant and a second color indicative of a wet refrigerant. The method also includes calculating an aggregated volume of each of the first color and the second color, wherein the aggregated volumes of the first color and the second color indicate a dry refrigerant or the wet refrigerant respectively in the stream. Further, the method includes comparing an aggregated volume ratio of the first color and the second color with a first threshold ratio and a second threshold ratio and determining the state as one of a dry state, a transient state, and a wet state based on the comparison.

Inventors

• Mateusz Mazur
• Leszek Wolski

Assignees

• CARRIER CORPORATION

Dates

Publication Date

20260512

Application Date

20231215

Claims (19)

1. 1 . A method for identifying a state of a stream of refrigerant, comprising: capturing, by an image sensor in a set of short-predefined intervals, a plurality of sample images of a sensor for sensing the stream of the refrigerant, wherein the sensor changes its color in response to one of presence or absence of humidity associated with the refrigerant in the stream, wherein a dry refrigerant is one associated with the absence of humidity and a wet refrigerant is one associated with the presence of humidity; processing each of the plurality of sample images to identify a plurality of colors, wherein a first color among the plurality of colors is indicative of the dry refrigerant and a second color among the plurality of colors is indicative of the wet refrigerant; calculating, for a long-predefined interval, an aggregated volume of each of the first color and the second color corresponding to the plurality of processed sample images, wherein the aggregated volumes of the first color and the second color are indicative of a volume of the dry refrigerant and the wet refrigerant respectively in the stream; comparing an aggregated volume ratio of the first color and the second color with a first threshold ratio and a second threshold ratio; and determining the state as one of a dry state, a transient state, and a wet state based on the comparison.
2. 2 . The method of claim 1 , wherein the aggregated volume ratio corresponds to a ratio of the aggregated volumes of the first color and the second color.
3. 3 . The method of claim 1 , comprising: identifying a third color from the plurality of colors corresponding to an abnormal image sensor operation due to lack of illumination; calculating, for the long-predefined interval, an aggregated volume of third color corresponding to the plurality of processed sample images, wherein the aggregated amount of the third color is indicative of a volume of the third color; comparing the calculated aggregated volume of the third color with a third threshold ratio; determining an abnormality in the plurality of captured sample images based on the comparison.
4. 4 . The method of claim 1 , wherein the state of the stream is determined as the dry state if the ratio is greater than the first threshold ratio.
5. 5 . The method of claim 1 , wherein the state of the stream is determined as the transient state if the ratio is less than the first threshold ratio and greater than the second threshold ratio.
6. 6 . The method of claim 1 , wherein the state of the stream is determined as the wet state if the ratio is less than the second threshold ratio.
7. 7 . The method of claim 1 , comprising: sensing, by a temperature sensor, a temperature of the refrigerant; and setting a value of each of the first threshold ratio and the second threshold ratio based on the sensed temperature.
8. 8 . An apparatus for sensing a state of a stream of refrigerant, comprising: a moisture sensor in fluid communication with the stream of refrigerant and adapted to changes color in response to one of presence or absence of humidity associated with the refrigerant in the stream, wherein a dry refrigerant is one associated with the absence of humidity and a wet refrigerant is one associated with the presence of humidity; an image sensor installed proximate to the moisture sensor and adapted to capture a plurality of images of the sensor; and a processor configured to: control the image sensor to capture a plurality of sample images of the sensor in a set of short-predefined intervals for sensing the stream of the refrigerant; process each of the plurality of sample images to identify a plurality of colors, wherein a first color among the plurality of colors is indicative of the dry refrigerant and a second color among the plurality of colors is indicative of the wet refrigerant; calculate, for a long-predefined interval, an aggregated volume of each of the first color and the second color corresponding to the plurality of processed sample images, wherein the aggregated volumes of the first color and the second color are indicative of a volume of the dry refrigerant and the wet refrigerant respectively in the stream; compare an aggregated volume ratio of the first color and the second color with a first threshold ratio and a second threshold ratio; and determine the state as one of a dry state, a transient state, and a wet state based on the comparison.
9. 9 . The apparatus of claim 8 , wherein the aggregated volume ratio corresponds to a ratio of the aggregated volumes of the first color and the second color.
10. 10 . The apparatus of claim 8 , wherein the processor is further configured to: identify a third color from the plurality of color corresponding to an abnormal image sensor operation due to lack of illumination; calculate, for the long-predefined interval, an aggregated volume of third color corresponding to the plurality of processed sample images, wherein the aggregated amount of black color is indicative of a volume of the abnormal image sensor operation due to lack of illumination; compare the calculated aggregated volume of the third color with a third threshold ratio; determine an abnormality in the plurality of captured sample images based on the comparison.
11. 11 . The apparatus of claim 8 , wherein the state of the stream is determined as the dry state if the ratio is greater than the first threshold ratio.
12. 12 . The apparatus of claim 8 , wherein the state of the stream is determined as the transient state if the ratio is less than the first threshold ratio and greater than the second threshold ratio.
13. 13 . The apparatus of claim 8 , wherein the state of the stream is determined as the wet state if the ratio is less than the second threshold ratio.
14. 14 . The apparatus of claim 8 , comprising a temperature sensor adapted to sense a temperature of the stream of refrigerant, wherein the processor is adapted to set a value of each of the first threshold ratio and the second threshold ratio based on the sensed temperature.
15. 15 . A non-transitory computer-readable medium having stored thereon computer-executable instructions which, when executed by a processor of an apparatus, cause the apparatus to execute operations for identifying a state of a stream of refrigerant, the operations comprising: capturing, by an image sensor in a set of short-predefined intervals, a plurality of sample images of a sensor for sensing the stream of the refrigerant, wherein the sensor changes its color in response to one of presence or absence of humidity associated with the refrigerant in the stream, wherein a dry refrigerant is one associated with the absence of humidity and a wet refrigerant is one associated with the presence of humidity; processing each of the plurality of sample images to identify a plurality of colors, wherein a first color among the plurality of colors is indicative of the dry refrigerant and a second color among the plurality of colors is indicative of the wet refrigerant; calculating, for a long-predefined interval, an aggregated volume of each of the first color and the second color corresponding to the plurality of processed sample images, wherein the aggregated volumes of the first color and the second color are indicative of a volume of the dry refrigerant and the wet refrigerant respectively in the stream; comparing an aggregated volume ratio of the first color and the second color with a first threshold ratio and a second threshold ratio; and determining the state as one of a dry state, a transient state, and a wet state based on the comparison.
16. 16 . The non-transitory computer-readable medium of claim 15 , wherein the aggregated volume ratio corresponds to a ratio of the volume of the first color and the second color.
17. 17 . The non-transitory computer-readable medium of claim 15 , wherein the operation comprises: identifying a third color from the plurality of color corresponding to an abnormal image sensor operation due to lack of illumination; calculating, for the long-predefined interval, an aggregated volume of third color corresponding to the plurality of processed sample images, wherein the aggregated amount of black color is indicative of a volume of the abnormal image sensor operation due to lack of illumination; comparing the calculated aggregated volume of the third color with a third threshold ratio; determining an abnormality in the plurality of captured sample images based on the comparison.
18. 18 . The non-transitory computer-readable medium of claim 15 , wherein the state is determined as the dry state if the ratio is greater than the first threshold ratio; the state of the stream is determined as the transient state if the ratio is less than the first threshold ratio and greater than the second threshold ratio; and the state of the stream is determined as the wet state if the ratio is less than the second threshold ratio.
19. 19 . The non-transitory computer-readable medium of claim 15 , wherein the operation comprises: sensing, by a temperature sensor, a temperature of the refrigerant; and setting a value of each of the first threshold ratio and the second threshold ratio based on the sensed temperature.

Description

CROSS REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Patent Application No. 63/477,628 filed on Dec. 29, 2022 which is incorporated herein in its entirety. FIELD OF THE INVENTION The disclosure relates to aspects of identifying a state of a stream of refrigerant. BACKGROUND A refrigeration system includes various pipes and hoses that supply refrigerant to different components of the refrigeration system, such as a compressor, a condenser, an expansion valve, or an evaporator. Some of the hoses may include a sight glass having a moisture sensor adapted to sense the wet refrigerant in a stream of refrigerant flowing through the hose. Generally, the moisture sensor changes color in the presence of the wet refrigerant or dry refrigerant. The moisture sensor, though able to sense the presence of wet refrigerant, is not capable of determining the volume of wet refrigerant inside the stream. Such information may be needed to plan service or repair or change operating parameters to remove the wet refrigerant from the stream and improve the performance of the refrigeration system. SUMMARY This summary is provided to introduce a selection of concepts, in a simplified format, that are further described in the detailed description of the invention. This summary is neither intended to identify key or essential inventive concepts of the invention and nor is it intended for determining the scope of the invention. The disclosure relates to a technique for determining a state of a stream of refrigerant. The technique involves gathering and processing image samples for short time intervals and aggregating the processed information to determine whether the stream is wet, dry, or in a transient state. Disclosed herein is a method for identifying a state of a stream of refrigerant. The method includes capturing, by an image sensor in a set of short-predefined intervals, a plurality of sample images of a sensor for sensing the stream of the refrigerant, wherein the sensor changes its color in response to one of presence or absence of humidity associated with the refrigerant in the stream, wherein a dry refrigerant is one associated with the absence of humidity and a wet refrigerant is one associated with the presence of humidity; processing each of the plurality of sample images to identify a plurality of colors, wherein a first color among the plurality of colors is indicative of a dry refrigerant and a second color among the plurality of colors is indicative of a wet refrigerant; calculating, for a long-predefined interval, an aggregated volume of each of the first color and the second color corresponding to the plurality of processed sample images, wherein the aggregated volumes of the first color and the second color are indicative of a volume of the dry refrigerant and the wet refrigerant respectively in the stream; comparing an aggregated volume ratio of the first color and the second color with a first threshold ratio and a second threshold ratio; and determining the state as one of a dry state, a transient state, and a wet state based on the comparison. In some embodiments, the aggregated volume ratio corresponds to a ratio of the volume of the first color and the second color. In some embodiments, the method includes identifying a third color from the plurality of color corresponding to an abnormal image sensor operation due to lack of illumination. The method further includes calculating, for a long-predefined interval, an aggregated volume of third color corresponding to the plurality of processed sample images, wherein the aggregated amount of black color is indicative of a volume of the abnormal image sensor operation due to lack of illumination. The method also includes comparing the calculated aggregated volume of the third color with a third threshold ratio and determining the state as an abnormal state based on the comparison. In some embodiments, the state of the stream is determined as the dry state if the ratio is greater than the first threshold ratio. In some embodiments, the state of the stream is determined as the transient state if the ratio is less than the first threshold ratio and greater than the second threshold ratio. In some embodiments, the state of the stream is determined as the wet state if the ratio is less than the second threshold ratio. In some embodiments, the method includes sensing, by a temperature sensor, a temperature of the refrigerant; and setting a value of each of the first threshold ratio and the second threshold ratio based on the sensed temperature. In some embodiments, an apparatus for sensing a state of a stream of refrigerant is disclosed. The apparatus includes a moisture sensor in fluid communication with the stream of refrigerant and is configured to change color in response to one of presence or absence of humidity associated with the refrigerant in the stream, wherein a dry refrigerant is one associated with the absence of hum