MUFFLERS FOR REFRIGERANT COMPRESSORS

CROSS-REFERENCED TO RELATED APPLICATION

[0001]This application is a 371 application of International Application No. PCT/US2023/023194, filed May 23, 2023, which claims priority to U.S. Provisional Application No. 63/356,020, which was filed on Jun. 27, 2022.

BACKGROUND

[0002]Refrigerant compressors are used to circulate refrigerant in a chiller via a refrigerant loop. Refrigerant loops are known to include a condenser, an expansion device, and an evaporator. The compressor compresses the fluid, which then travels to a condenser, which in turn cools and condenses the fluid. The refrigerant then goes to an expansion device, which decreases the pressure of the fluid, and to the evaporator, where the fluid is vaporized, completing a refrigeration cycle.

SUMMARY

[0003]A refrigerant compressor according to an example of this disclosure includes a discharge portion and a muffler disposed at the discharge portion. The muffler includes an outer cylinder having a center axis, and a sleeve concentric with and radially inward of the outer cylinder relative to the center axis. The sleeve includes a plurality of radially extending through holes and provides a resonance cavity radially between the sleeve and the outer cylinder.

[0004]In a further example of the foregoing, the muffler is attached to the discharge portion.

[0005]In a further example of any of the foregoing, the resonance cavity is sealed at its axial ends.

[0006]In a further example of any of the foregoing, a plurality of axially spaced annular plates are located within the resonance cavity.

[0007]In a further example of any of the foregoing, each of the plurality of annular plates include a plurality of axially extending through holes.

[0008]In a further example of any of the foregoing, the plurality of axially extending through holes are equally circumferentially spaced from one another.

[0009]In a further example of any of the foregoing, the radially extending through holes form axially spaced circumferential rows of radially extending through holes.

[0010]In a further example of any of the foregoing, the plates are positioned axially between, and radially outward of, immediately adjacent of the circumferential rows.

[0011]In a further example of any of the foregoing, the axially extending through holes are circumferentially aligned across two or more of the plates.

[0012]In a further example of any of the foregoing, the radii of the axially extending through holes are greater than the radii of the radially extending through holes.

[0013]In a further example of any of the foregoing, the radially extending through holes are equally circumferentially spaced from one another.

[0014]In a further example of any of the foregoing, the sleeve is welded to the cylinder.

[0015]In a further example of any of the foregoing, the muffler is configured to receive fluid from the discharge portion into the sleeve.

[0016]A method according to an example of this disclosure includes providing a muffler fluidly between a discharge portion of a compressor and a condenser. The muffler includes an outer cylinder including an inner diameter surface and a center axis, and a sleeve concentric with the outer cylinder. The sleeve includes a plurality of radially extending through holes and provides a resonance cavity radially between the outer cylinder and the sleeve.

[0017]In a further example of the foregoing, a plurality of axially spaced annular plates are located within the resonance cavity, each of the plurality of annular plates include a plurality of axially extending through holes.

[0018]In a further example of any of the foregoing, the radially extending through holes form axially spaced circumferential rows of radially extending through holes, and provide the plurality of axially spaced annular plates step, which includes positioning the plurality of annular plates axially between, and radially outward of, immediately adjacent of the circumferential rows.

[0019]In a further example of any of the foregoing, the resonance cavity is sealed at its axial ends.

[0020]In a further example of any of the foregoing, the sleeve is welded to the outer cylinder.

[0021]In a further example of any of the foregoing, the muffler is attached to the discharge portion.

[0022]In a further example of any of the foregoing, the muffler is configured to receive fluid from the discharge portion into the sleeve.

[0023]These and other features may be best understood from the following specification and drawings, the following of which is a brief description.

BRIEF DESCRIPTION OF THE DRAWINGS

[0024]FIG. 1 schematically illustrates a refrigerant system.

[0025]FIG. 2 illustrates an example compressor.

[0026]FIG. 3 illustrates an example muffler.

[0027]FIG. 4 schematically illustrates flow through the example muffler of FIG. 3.

[0028]FIG. 5 illustrates another example muffler.

[0029]FIG. 6 schematically illustrates flow through the example muffler of FIG. 5.

DETAILED DESCRIPTION

[0030]This disclosure relates generally to refrigerant compressors, and more particularly to mufflers at a discharge portion of a refrigerant compressor. The systems and methods disclosed herein have been found to decrease the noise output of refrigerant compressors. The term “muffler” as used herein is intended to refer to all types of noise reduction devices and is not intended to be limited to any size or shape.

[0031]FIG. 1 schematically illustrates a refrigerant cooling system 10. The refrigerant system 10 includes a main refrigerant loop, or circuit, 12 in communication with a compressor or multiple compressors 14, a condenser 13, an evaporator 15, and an expansion device 17. This refrigerant system 10 may be used in a chiller or heat pump, for example. While a particular example of the refrigerant system 10 is shown, this disclosure extends to other refrigerant system configurations. For instance, the main refrigerant loop 12 can include an economizer downstream of the condenser 13 and upstream of the expansion device 17. The refrigerant cooling system 10 may be an air conditioning system, for example.

[0032]FIG. 2 illustrates an example compressor 14 including a discharge portion 20 where refrigerant exits the compressor 14 before flowing to the condenser 13 (see FIG. 1). The example discharge portion 20 is where refrigerant exits the compressor 14, as opposed to a location between compressor stages. Although an example compressor 14 is shown, other types of compressors may benefit from this disclosure.

[0033]FIG. 3 illustrates an example muffler 22, which may be provided at the area A (FIG. 1) fluidly between the compressor 14 and the condenser 13. In some examples, the muffler 22 may be attached to, or otherwise positioned near, the discharge portion 20 (FIG. 2) of the compressor 14. The example muffler 22 includes a hollow outer cylinder 24 having a center axis 26. The outer cylinder 24 is shown as transparent for ease of viewing the other components of the example muffler 22. A cylindrical sleeve 28 is concentric with and radially inward of the outer cylinder 24. The sleeve 28 includes a plurality of radially extending through holes 30. An axially extending annular resonance cavity 32 is provided radially between the radially inner surface 34 of the outer cylinder 24 and the radially outer surface 36 of the sleeve. The example resonance cavity 32 is sealed at axial ends of the cylinder 24 and sleeve 28.

[0034]As shown schematically in FIG. 4, with continued reference to FIG. 3, the discharge flow from the discharge portion 20 of the compressor 14 enters the muffler 22 with leftover swirl from the input rotational energy produced by the compressor impeller. The flow enters the muffler 22 into the sleeve 28. As the flow enters and flows axially through the muffler 22, a portion of the fluid is directed radially outward through the radially extending through holes 30, being reoriented to the resonance cavity 32 and creating pressure wave reflections in the flow that, in turn, generate reflective waves that cancels the naturally incoming pressure waves. The result is a decrease in overall noise generation from the compressor 14.

[0035]Refrigerant enters the muffler 22 at one axial end 40 of the sleeve 28 and exits the muffler 22 at an opposite axial end 42 of the sleeve 28. Because the resonance cavity 32 is sealed at the axial ends, refrigerant flows back radially inward of the radially inner surface 44 of the sleeve 28 before exiting the muffler 22 at the axial end 42. In some examples, as shown, the resonance cavity 32 is sealed at its axial ends by annular radially inwardly extending extensions 43 received against the sleeve 28. In the example, the resonance cavity 32 receives fluid through the through holes 30 of the sleeve 28 rather than being fed fluid directly from the discharge portion 20 at its axial end.

[0036]The muffler 22 design can be finely tuned to reflect specific wavelengths that exhibit the highest level of noise in the compressor operation, such as through sizing the holes 30 and their spacing to generate noise at desired frequencies. In some examples, the radially extending through holes 30 are equally circumferentially spaced from one another.

[0037]In some examples, the sleeve 28 is manufactured separately, according to the desired application, and fixed to the cylinder 24, such as by mechanical connection or welding in some examples.

[0038]FIGS. 5 and 6 illustrate another example muffler 122 substantially similar to the muffler 122 except that a plurality of axially spaced annular plates 146 are provided within the resonance cavity 132. It should be understood that like reference numerals identify corresponding or similar elements throughout the several drawings. One or more or each of the example plates 146 includes a plurality of circumferentially spaced axially extending through holes 148. In some examples, as shown, the radially extending through holes 130 of the sleeve 128 form axially spaced circumferential rows of through holes 130, and the plates 146 are positioned axially between, and radially outward of, immediately adjacent rows. The example plates 146 are disk-shaped, extending a full circumference.

[0039]The usage of additional plates 146 allows for more frequencies to be resonated within the system, and the decrease of noise generation of multiple frequencies. The muffler 122 design can be finely tuned to reflect specific wavelengths that exhibit the highest level of noise in the compressor operation. This is done by sizing the holes and their spacing in both the sleeve 128 and in the plates 146 to generate noise at desired frequencies.

[0040]In some examples, the axially extending through holes 148 are equally circumferentially spaced from one another. In some examples, as shown, the axially extending through holes 148 are circumferentially aligned across two or more of the plates 146. In some examples, as shown, the axially extending through holes 148 are circumferentially aligned with adjacent radially extending through holes 130. In some examples, as shown, the radii of the axially extending through holes 148 are greater than the radii of the radially extending through holes 130. Applicant has found that the above examples can be utilized to resonate noise at certain frequencies.

[0041]FIG. 6 schematically illustrates flow through the example muffler 122 of FIG. 5.

[0042]A method in view of the above examples may be said to include providing a muffler 22/122 fluidly between a discharge portion of a compressor and a condenser, the muffler including a hollow outer cylinder including an inner diameter surface and a center axis, and a hollow inner cylinder or sleeve concentric with the outer cylinder and including a plurality of radially extending through holes.

[0043]An example refrigerant compressor may be said to include a discharge portion and a muffler at the discharge portion. The muffler includes an outer cylinder having a center axis, and a sleeve concentric with, and radially inward of, the outer cylinder relative to the center axis. The sleeve includes a plurality of radially extending through holes, providing a resonance cavity radially between the sleeve and the outer cylinder.

[0044]The foregoing description shall be interpreted as illustrative. A worker of ordinary skill in the art would understand that certain modifications could come within the scope of this disclosure. Various examples of the disclosure have been described. Any combination of the described systems, operations, or functions is contemplated. It is possible to use some of the components or features from any of the examples in combination with features or components from any of the other examples. These and other examples are within the scope of the following claims.