Multi-channel diffuser

Abstract

A multi-channel diffuser (MCD) has a plurality of radial inlets in an annular configuration, a tangential outlet, a single discharge passage, and a plurality of separation passages extending from the plurality of radial inlets and toward the outlet. The plurality of separation passages are fluidly isolated from each other at their upstream ends and converge at one or more convergence locations upstream of the single discharge passage. Thus, fluid streams entering the plurality of radial inlets are initially separated within the plurality of separation passages, converge within a single discharge passage, and then collectively flow out of the MCD through the outlet. The mixing loss and the viscosity loss are reduced.

Description

[0001] Cross-references to related applications

[0002] This application, filed on June 26, 2023, is entitled " MULTIPLE CHANNEL DIFFUSER (MULTIPLE CHANNEL DIFFUSER) compressor The entire contents of U.S. Patent Application No. 18 / 213,990, which is related to and claims priority to, are incorporated herein by reference. Technical Field

[0003] This technology generally relates to a pump or compressor, and more specifically to a diffuser for a pump or compressor. Background Technology

[0004] In pumps or compressors such as turbopumps, diffusers are typically used to convert the dynamic pressure of the fluid flow leaving the pump or compressor into a static pressure increase at the volute outlet. There are three commonly used diffusers: bladeless diffusers, airfoil diffusers, and island diffusers. The single largest loss in a turbopump is in the diffuser, and diffuser losses can account for more than 20% of the total pressure loss from the impeller outlet to the volute. This loss originates from the leading edge (incident loss), trailing edge (expansion loss), mixing loss, and / or skin friction loss. Of these losses, mixing loss is the largest and accounts for more than 90% of the total loss.

[0005] The mixing losses are greatest due to the large pressure and velocity gradient between the diffuser and the volute. An additional contribution to the losses is the asymmetry caused by the volute tongue, which also induces a circumferential hydrostatic gradient around the volute, propagating to the impeller through the diffuser. The volute tongue is a major contributor to the radial side load acting on the bearing from the impeller; however, eliminating the tongue and the circumferential pressure gradient eliminates this side load, increasing bearing life and reliability.

[0006] Furthermore, once the radial component of the kinetic energy, along with the meridional dynamic pressure, enters the volute, this radial component is almost irrecoverable. Leading-edge or incident losses are due to stagnation conditions caused by the leading edge and any misalignment between the flow field streamlines and the leading edge. Even if these are perfectly aligned under design point conditions (which is impossible), incident losses will occur under deviated design conditions. Trailing-edge losses are caused by the pressure gradient between the pressure side and the suction side of the diffuser. These losses even exist in symmetrical blades, but are larger in asymmetrical blades with rotation due to the increased pressure and velocity gradient between the pressure side and the suction side. Skin friction losses are caused by the velocity of the moving fluid in contact with the stationary wall. These losses can be significant in pumps with viscous fluids; however, they are negligible for refrigerants such as hydrogen, oxygen, and methane, as these are almost non-viscous. Even non-refrigerants with low viscosity, including rocket propellants and any low-viscosity fluid such as water, will have relatively low skin friction losses. To highlight the magnitude of the mixing loss, it is worth noting that bladeless diffusers do not have leading or trailing edge losses, but are still the least efficient diffusers due to their high mixing losses. Summary of the Invention

[0007] Some embodiments advantageously provide a multichannel diffuser (MCD), such as the MCD used in turbomachinery.

[0008] In one embodiment, an MCD includes: a plurality of inlets arranged in a ring; an outlet; and a plurality of separation passages extending from the plurality of inlets toward the outlet, each of the plurality of separation passages having an increased flow area, the plurality of separation passages being fluidly isolated from each other at an upstream end and converging at one or more confluence locations upstream of the outlet.

[0009] In one aspect of the embodiment, multiple separate paths are configured in multiple rows, wherein each row has multiple diffuser channels.

[0010] In one aspect of the embodiment, the plurality of inlets are radial inlets.

[0011] In one aspect of the embodiment, the outlet is a tangential outlet.

[0012] In one aspect of the embodiment, the outlet has a square cross-section or a circular cross-section.

[0013] In one aspect of the embodiments, each of the plurality of separate pathways has one of a straight, hexagonal, and elliptical cross-sectional shape.

[0014] In one embodiment, a multichannel diffuser (MCD) includes: a plurality of inlets arranged in annular arrangement; an outlet; and a plurality of separation passages extending from the plurality of inlets toward the outlet, each of the plurality of separation passages having an upstream end and a downstream end, the upstream end of each of the plurality of separation passages being located at a corresponding inlet of the plurality of inlets, each of the plurality of separation passages having a flow area increasing from the upstream end to the downstream end, the plurality of separation passages being fluidly isolated from each other at the upstream end and converging at one or more converging locations upstream of the outlet.

[0015] In one aspect of the embodiment, multiple separate paths are configured in multiple rows, wherein each row has multiple diffuser channels.

[0016] In one aspect of the embodiments, one or more merging locations include an upstream merging location and a downstream merging location. In one aspect of the embodiments, the MCD also includes a single emission pathway located between the downstream merging location and an outlet. In one aspect of the embodiments, at least two of a plurality of separate pathways merge at the upstream merging location, and at least two other of the plurality of separate pathways merge at the downstream merging location.

[0017] In one aspect of the embodiments, each of the plurality of separate pathways has one of a straight, hexagonal, and elliptical cross-sectional shape.

[0018] In one aspect of the embodiments, a multi-channel diffuser defines an orifice that is sized and configured to receive at least a portion of a pump impeller therein. In one aspect of the embodiments, a plurality of annularly arranged inlets extend around the orifice. In one aspect of the embodiments, a plurality of separate passages extend around the orifice. Attached Figure Description

[0019] A more complete understanding of the embodiments described herein and their accompanying advantages and features will be more readily understood when considered in conjunction with the accompanying drawings, by referring to the following detailed description, wherein:

[0020] Figure 1 A cross-sectional view of an exemplary embodiment of the multichannel diffuser (MCD) according to the present invention is shown;

[0021] Figure 2 The following is shown in accordance with this disclosure: Figure 1 A side perspective view of the structural model of the MCD;

[0022] Figure 3 It shows Figure 1 A three-dimensional view of the flow volume of the MCD; and

[0023] Figure 4 The following is shown in accordance with this disclosure:Figure 1 The front view of the MCD shows the main exhaust port and the merge channel. Detailed Implementation

[0024] Before describing the exemplary embodiments in detail, it should be noted that the embodiments primarily exist in combinations of equipment components and steps associated with diffusers for pumps or compressors, and more specifically with multi-channel diffusers (MCDs) for pump or compressor turbomachinery, wherein the MCD includes an annular radial inlet and a tangential outlet, wherein multiple passages are separated from each other to limit fluid mixing, but these passages then converge at one or more locations upstream of the outlet of the MCD. Thus, system and method components have been appropriately indicated in the drawings by conventional symbols, showing only those specific details relevant to understanding embodiments of this disclosure, so as not to obscure the disclosure with details that would be clear to those skilled in the art who benefit from the description herein.

[0025] Now referring to the accompanying drawings, in which the same reference numerals are used for the same elements, Figures 1 to 4 An exemplary embodiment of the MCD is illustrated. In one embodiment, the MCD 10 typically includes an outlet 12 and a plurality of inlets 14. In one embodiment, the MCD 10 also includes a plurality of separation pathways 16 extending from each of the plurality of inlets 14 toward the outlet 12; however, the plurality of separation pathways 16 merge into a single emission pathway 18 at at least one confluence location 20 upstream of the outlet 12. In one embodiment, the plurality of pathways 16 includes nine pathways 16 (e.g., as shown in the image). Figure 1 Cross-sectional view and Figure 3 The flow volume diagram shown illustrates how... Figure 1 , Figure 2 and Figure 4 The MCD 10 shown internally routes the fluid. However, it should be understood that more or fewer passages may be included. In one embodiment, the MCD 10 is stationary, and an impeller rotates within the MCD 10, discharging fluid outward in a annular arrangement and into multiple inlets of the MCD 10.

[0026] Continue to refer to Figures 1-4 In one embodiment, the MCD 10 is generally annular and configured to extend around an impeller, defining an orifice 22 in which the impeller can be disposed. In one embodiment, each of the plurality of inlets 14 is arranged radially around an imaginary center point 24 of the orifice 22 within the MCD 10 (radial inlet). In one embodiment, the MCD 10 is stationary, and the impeller rotates within the MCD 10 (e.g., within its position within the orifice 22) and discharges fluid outward in an annular arrangement into the plurality of inlets of the MCD 10.

[0027] In one embodiment, each of the plurality of separation channels 16 has an upstream end 16A and a downstream end 16B, and the upstream end 16A of each of the plurality of separation channels 16 encounters, is located at, near, and / or at least partially defines, and is in fluid communication with, a corresponding inlet of the plurality of inlets 14. In one embodiment, each of the plurality of separation channels 16 has a gradually increasing cross-sectional area extending from the associated inlet 14 at the upstream end 16A toward the downstream end 16B and the outlet 12. Furthermore, each of the plurality of separation channels 16 is fluidly isolated from each of the other separation channels 16 until the plurality of separation channels 16 converge at one or more confluence locations 20. Therefore, the fluid within each of the plurality of separation paths 16 remains isolated from the fluid within any of the other separation paths 16, but subsequently becomes mixed with fluid from at least one of the other separation paths 16 at a location upstream of the single discharge path 18 and outlet 12, wherein all separation paths 16 have already converged upon encountering the single discharge path 18 to allow the fluid to flow collectively out of outlet 12. Each of the plurality of separation paths 16 acts as an individual diffuser without mixing with other fluids until the convergence point 20 and the single discharge path 18, wherein the fluids are allowed to combine along parallel streamlines that eliminate mixing losses. In some embodiments, the fluid isolation of the plurality of separation paths 16 from the plurality of inlets 14 eliminates mixing losses; however, the convergence of the fluid flow within the single discharge path 18 before exiting outlet 12 also reduces viscous losses.

[0028] Continue to refer to Figures 1-4 In one embodiment, the MCD 10 includes more than one confluence location 20, wherein the most downstream confluence location is at an upstream portion 18A of a single emission path 18. In one embodiment, a downstream portion 18B of the single emission path 18 defines an outlet 12. As an example, in one embodiment, some (less than all) of a plurality of divergence paths 16 converge at at least one upstream confluence location 20A, and others (less than all) of the plurality of divergence paths 16 converge at or near an upstream portion 18A of a single emission path 18, at a downstream or most downstream confluence location 20B (e.g., as shown in the image). Figure 1(As shown). Regardless of the number of merging points 20, fluid flows as a converging fluid from multiple separate passages 16 across the length of a single discharge passage 18 before exiting the MCD 10 through outlet 12. In one embodiment, the gaps between separate passages 16 are eliminated when the passages are in circumferential and axial positions sufficient to form a common and uniform structural wall, thereby allowing, for example, two of the separate passages 16 to merge before reaching a common merging point (such as an upstream merging point 20A or a downstream merging point 20B, etc., at or near discharge passage 18). These merging points occur as a percentage of the total passage length relative to the inlet 14 location and discharge passage 18, where the larger passage length has a smaller percentage of the total length, until merging may occur. In other words, in some embodiments, each separate passage 16 travels a percentage of its total length before merging with another separate passage 16. In a non-limiting example, the percentage is reduced based on the total length of the separation pathway 16, wherein the shortest separation pathway 16 may travel approximately 100% (±5%) of its length before merging, and the longest separation pathway 16 may travel only approximately 10% (±5%) of its length before merging.

[0029] exist Figure 4 This exemplary configuration is shown in the front view of the MCD 10.

[0030] Through outlet 12, a single emission path 18 can be seen terminating at outlet 12 in its downstream portion 18B. Within this single emission path 18, some of the multiple diverging paths 16 are visible because they converge at a downstream confluence location 20, while other paths of the multiple diverging paths 16 converge at a more upstream confluence location 20 (e.g., as...). Figure 1 (as shown), and the separate separation path 16 is no longer visible through the outlet 12 near the single emission path 18. Furthermore, as... Figure 3 and Figure 4 As shown and described in more detail below, in some embodiments, the plurality of separation passages 16 begin radially at the plurality of inlets 14 and spiral out in a slightly helical arrangement to form a more matrix-like or grid-like arrangement at or near the upstream portion 18A of a single discharge passage 18. In one example, the plurality of separation passages 16 are arranged to form a plurality of rows, each row including one or more separation passages 16 to form a matrix-like or grid-like arrangement.

[0031] also, Figures 1-4The embodiment of the MCD 10 shown includes radial inlets (i.e., a plurality of radially arranged inlets) with tangential outlets. However, in other embodiments, the MCD 10 includes axial inlets (i.e., a plurality of axially arranged inlets) and non-tangential outlets. For example, an axial flow pump or compressor may discharge fluid flow into an annular arrangement of axial inlets, each axial inlet having a passage separate from the other axial inlets, such that each axial inlet discharges into a single discharge passage 18 that is not tangential to the axis of the pump or compressor.

[0032] Continue to refer to Figures 1-4 In one embodiment, the outlet 12 of the MCD 10 has a circular or annular cross-sectional shape. However, it should be understood that the outlet 12 can have any suitable cross-sectional shape, including but not limited to circular, square, polygonal (e.g., hexagonal), straight line, elliptical, etc. Furthermore, each of the plurality of separation channels 16 is shown as having a square cross-sectional shape. However, it should be understood that other suitable cross-sectional shapes, including but not limited to circular, polygonal, straight line, elliptical, etc., can be used.

[0033] In some embodiments, the MCD 10 includes one or more additional features. For example, in one embodiment, one or more of the plurality of separation paths 16 are separated from the other separation paths 16 to define an outflow path for a portion of the fluid flow. In some embodiments, one or more second-stage emission configurations are used such that the MCD 10 includes more than a single emission section, one or more outlets, and one or more sets of separation paths 16.

[0034] Continue to refer to Figures 1-4 In one embodiment, the leading edge 26 of the MCD 10 is similar to the leading edge of an airfoil diffuser, except that each of the plurality of separation passages 16 is unique and extends and continuously expands to define an increased cross-sectional diameter as it winds around the orifice 22 and around the impeller (in use) (thereby expanding the flow of fluid). Figures 1 to 4 Each diagram illustrates how multiple separate pathways 16 are distributed internally to achieve [the desired effect]. Figure 4The matrix or grid-like arrangement is partially shown in the front view. In one embodiment, the MCD 10 is a conical diffuser with a square, rhomboid, trapezoidal, rectangular, or other suitable cross-sectional shape. In one embodiment, the diffusion angle is very small due to the length, which enables efficient diffusion with minimal loss. For example, in some embodiments, the diffusion angle is between about 0° and about 15° (± 0.05±°) depending on the specific application requirements. In one embodiment, after the dynamic pressure has diffused to the static pressure rise, the multiple separation paths 16 then converge within a single discharge path 18, creating a volute discharge port that functions similarly to the discharge element used in currently known diffusers. Furthermore, since each of the multiple separation paths 16 is independent of the others, the separation paths 16 can be bundled or separated and redirected for other purposes and configurations. For the same reason, the multiple separation paths 16 can additionally or alternatively be configured as a planar arrangement rather than a bundle to achieve various package configurations.

[0035] MCD 10 eliminates mixing and viscous losses, resulting in a greater increase in pressure recovery. In some embodiments, the dynamic pressure of the impeller discharge pressure gradually and effectively expands within multiple fluid-isolated, separate passages 16. Once the fluid flow has fully expanded, it merges and combines with adjacent passages after the confluence point 20 within a single discharge passage 18.

[0036] However, because the flow is fully extended (and because there are no turns), there is no significant pressure or velocity gradient that would cause mixing losses. Keeping the turbopump, engine size, and stage constant results in increased chamber pressure to accommodate additional stage capacity (higher track, higher track inclination, and / or heavier payload).

[0037] Alternatively, while maintaining specific impact and thrust constants, both the maximum diameter and overall length are significantly reduced, resulting in smaller, lighter stages with significantly increased mission capabilities.

[0038] Diffusers and volutes typically have thick housings to accommodate high pressures. The discharge pressure is the same regardless of the diffuser or passage size. Therefore, wall thickness depends only on the passage size. A single large volute requires thick walls, while small passages require only thin walls, especially those separate passages 16 located outside other passages. Separate passages 16 located inside or surrounded by other separate passages 16 do not have a pressure gradient on their walls due to adjacent passages, and therefore can be even thinner. Thus, in addition to the weight reduction resulting from a smaller engine, further weight reduction is possible solely from the diffuser and volute housings of the MCD 10. Furthermore, the MCD 10 lacks the tongue (as seen in conventional volute and diffuser combinations), which virtually eliminates rotor-side loads in currently known diffuser systems, thereby providing improved rotor power and system life.

[0039] As used herein, relational terms such as “first” and “second,” “top” and “bottom” may be used solely to distinguish one entity or element from another, without necessarily requiring or implying any physical or logical relationship or order between such entities or elements. The terms used herein are for descriptive purposes.

[0040] The specific embodiments described herein are merely and not intended to limit the concepts described herein. As used herein, unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “the” are intended to also include the plural forms. It will be further understood that, when used herein, the terms “comprises,” “comprising,” “includes,” and / or “including” specify the presence of the stated feature, integral, step, operation, element, and / or component, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or combinations thereof.

[0041] Unless otherwise defined, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. It should be further understood that the terms used herein shall be interpreted as having the same meaning as they have in the context of this specification and the relevant field, and shall not be interpreted in an idealized or overly formal sense unless expressly defined herein.

[0042] Those skilled in the art will understand that the present invention is not limited to what has been specifically shown and described above. Furthermore, unless otherwise stated above, it should be noted that all drawings are not to scale. Based on the foregoing teachings, various modifications and variations are possible without departing from the scope and spirit of the invention.

Claims

1. A multi-channel diffuser, comprising: Multiple entrances arranged in a ring; exit; as well as Multiple separation paths extend from multiple inlets toward the outlet, each of the multiple separation paths having an upstream end and a downstream end, the upstream end of each of the multiple separation paths being located at a corresponding inlet among the multiple inlets, and each of the multiple separation paths having an increasing flow area from the upstream end to the downstream end. The plurality of separation pathways are fluidly isolated from each other at the upstream end and converge at one or more confluence locations upstream of the outlet.

2. The multi-channel diffuser according to claim 1, wherein, The multiple separation paths are configured in multiple rows, wherein each row has multiple diffuser channels.

3. The multi-channel diffuser according to claim 1, wherein, The plurality of inlets are radial inlets.

4. The multi-channel diffuser according to claim 1, wherein, The outlet is a tangential outlet.

5. The multi-channel diffuser according to claim 1, wherein, The outlet has a square or circular cross-section.

6. The multi-channel diffuser according to claim 1, wherein, Each of the plurality of separation pathways has one of a linear, hexagonal, or elliptical cross-sectional shape.

7. The multi-channel diffuser according to claim 1, wherein, The one or more merging locations include upstream merging locations and downstream merging locations.

8. The multichannel diffuser of claim 7 further includes a single discharge path located between the downstream confluence and the outlet.

9. The multi-channel diffuser according to claim 8, wherein, At least two of the plurality of separate pathways converge at the upstream confluence location, and at least two other separate pathways converge at the downstream confluence location.

10. The multi-channel diffuser according to claim 1, wherein, The multi-channel diffuser defines an orifice that is sized and configured to receive at least a portion of the pump impeller therein.

11. The multi-channel diffuser according to claim 10, wherein, The annular arrangement of the plurality of entrances extends around the orifice.

12. The multi-channel diffuser according to claim 11, wherein, The plurality of separation pathways extend around the orifice.

Images