Turning inlet duct

Abstract

A turning duct for a rotating machine includes an inlet disposed along a vertical axis of the turning duct. A flow divider is disposed within the inlet region and extends inward from a perimeter of the inlet towards the vertical axis. A bifurcation region is disposed downstream of the inlet region directing the fluid flow into a first bifurcated flow and a second bifurcated flow. A first turning region and a second turning region are downstream of the bifurcation region and receive and redirect the respective bifurcated flows from a first direction oriented along the vertical axis to a second direction oriented along a horizontal axis of the inlet duct. A convergence region is disposed downstream of the turning regions flared radially inward and directing the bifurcated flows to recombine. An annular region is disposed downstream of the convergence region and disposed about a horizontal axis of the turning duct.

Description

TURNING INLET DUCTBACKGROUND

[0001] Rotary machines, such as turbo-compressors, may be configured to receive a process fluid at an inlet and discharge a compressed fluid at an outlet. A fluid inlet duct may be used to direct a process fluid into the inlet.SUMMARY

[0002] Disclosed are multiple embodiments of a turning duct for a rotating machine including an inlet disposed along a vertical axis of the turning duct, a flow divider disposed within the inlet region extending at least partially radially inward from a perimeter of the inlet towards the vertical axis, a bifurcation region disposed downstream of the inlet region directing the fluid flow into a first bifurcated flow and a second bifurcated flow, a first turning region and a second turning region disposed downstream of the bifurcation region receiving the respective bifurcated flows and redirecting the bifurcated flows from a first direction oriented along the vertical axis to a second direction oriented along a horizontal axis of the inlet duct, a convergence region disposed downstream of the turning regions flared radially inward and directing the bifurcated flows to recombine, and an annular region disposed downstream of the convergence region and disposed about a horizontal axis of the turning duct.

[0003] Also disclosed are multiple embodiments of a method for providing a process fluid to a rotary machine, the method including receiving the process fluid at an inlet of a turning duct, bifurcating the process fluid using a flow divider and providing a first portion of the process fluid to a first turning region and a second portion of the process fluid to a second turning region, turning the respective portions of the process fluid from a radial direction to an axial direction, relative to an axis defined by an annular outlet, and outputting the process fluid through the annular outlet in an axial direction.BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0004] FIG. 1 illustrates a rotary machine including at least one turning inlet duct in accordance with an embodiment;

[0005] FIG. 2 illustrates a section of the turboheater machine of FIG. 1 including two sequentially arranged turning inlet ducts defining a process fluid flowpath in accordance with an embodiment;

[0006] FIG. 3A illustrates an isometric view of a turning inlet duct in accordance with an embodiment;

[0007] FIGS. 3B, 3C, 3D, and 3E schematically illustrate a rear (3B), side (3C), top (3D) and front (3E) view of the turning inlet duct of FIG. 3 A in accordance with an embodiment;

[0008] FIG. 4 illustrates a radially inward facing cross sectional view along of FIG. 3 A along cut line A-A in accordance with an embodiment;

[0009] FIG. 5 illustrates a side facing cross sectional view of FIG. 3 A along cut line B-B in accordance with an embodiment;

[0010] FIG. 6A illustrates a rear view of the turning inlet duct disposed about a bearing housing in accordance with an embodiment; and

[0011] FIG. 6B illustrates a cross sectional view of the turning inlet duct of FIG. 6A along cross section C-C in accordance with an embodiment.DETAILED DESCRIPTION

[0012] In the following detailed description, various specific details are set forth in order to provide a thorough understanding of such embodiments. However, those skilled in the art will understand that disclosed embodiments may be practiced without these specific details that the aspects of the present invention are not limited to the disclosed embodiments, and that aspects of the present invention may be practiced in a variety of alternative embodiments. In other instances, methods, procedures, and components, which would be well-understood by one skilled in the art have not been described in detail to avoid unnecessary and burdensome explanation.

[0013] Furthermore, various operations may be described as multiple discrete steps performed in a manner that is helpful for understanding embodiments of the present invention. However, the order of description should not be construed as to imply that these operations need be performed in the order they are presented, nor that they are even order dependent, unless otherwise indicated. Moreover, repeated usage of the phrase “in one embodiment” does not necessarily refer to the same embodiment, although it may.

[0014] It is noted that disclosed embodiments need not be construed as mutually exclusive embodiments, since aspects of such disclosed embodiments may be appropriately combined by one skilled in the art depending on the needs of a given application.

[0015] As used herein “approximately” with references to sizes, dimensions, shapes, and similar objects gives reference to the natural variation that can occur due to tolerances and manufacturing techniques. One of skill in the art can apprise the appropriate scope and scale of “approximately” based on the available and intended manufacturing techniques.

[0016] As used herein, “substantially identical geometries”, as well as any variation on the same term, refers to identical or similar shapes, with varying dimensions. By way of example, spheres of different sizes would have substantially identical geometries, despite the varying radius dimension.

[0017] This invention relates to turbomachine components to impart thermal energy into a fluid flow therethrough. In an example embodiment, the components disclosed herein are related to turbomachinery devices used to impart thermal energy to a process fluid (i.e. turboheater devices) such as those used to thermally decompose (crack) a high molecular weight hydrocarbon to lower molecular weight species. In some examples, these processes can benefit from two or more successive turboheater devices to achieve the desired chemical reaction. In such cases the inlet to the second device is part of the quiescent reaction zone where the chemical reaction is occurring after achieving a threshold activation energy via the upstream turboheater device.

[0018] Typically process fluid is transported through pipe runs. This flow must be directed to the active, annular, flowpath of the turboheater. Typically for turbomachines a rotor support system (i.e. bearing system) is present at the ends of the active flowpath. Therefore inlet of the turboheater connects the inlet pipe to the annular flowpath inlet while avoiding the space claim of the rotor support and the rotor itself. Furthermore, in some examples, due to the positioning of the source of the process fluid, the inlet of the process fluid to the elastic fluid turbomachine requires the fluid flow to turn from a radial direction to an axial direction, relative to an axis defined by the turbomachine. The turn can vary from as low as 15 degrees to more than 90 degrees in some examples. A most typical example turn will be at or near 90 degrees. When turning a process fluid, it is desirable to ensure that the flow is as close to even in both direction and velocity as possible in order to maintain optimum turboheater operations. In addition, the turning converts the flow from a pipe flow to an annular flow distributed around the internal components.

[0019] FIG. 1 shows an exemplary rotary machine 10, the exemplary rotary machine 10 includes a shaft 12 configured to rotate one or more impellers 14, with the impellers 14 drivinga fluid along a flowpath. The shaft may be driven to rotate via any motive source including, but not limited to, a turbine based drive system, an external source of rotation, magnetic field interactions, or any other similar source of rotation. Due to the specific components of any given rotational machine, and the corresponding fluid flow requirements, some systems require a radial, flow to be received and turned to an annular axial flow aligned with, and disposed about, an axis 30 defined by the rotary machine 10. To accommodate this flow, as well as the rotating components internal to the flowpath, the rotary machine 10 includes an inlet turning duct 20 configured to receive an inlet flow in a radial direction at an inlet portion, or an at last partially radial direction, and turns the fluid flow to an axial direction at an annular outlet portion 26. As used herein, “partially radial” can include any angle greater than about 15 degrees. In one example, the rotary machine 10 is a chemical reactor for cracking a hydrocarbon in a process fluid and the fluid received and turned by the inlet turning duct 20 is the process fluid. In another example, the rotary machine 10 is an electric generator / motor and the fluid received and turned by the inlet turning duct 20 is a cooling fluid such as air or oil.

[0020] In some embodiments at least two or more of the rotary machines 10, with sequential axial impulse impellers 14 are utilized. FIG. 2 illustrates one example two stage system where the reactors are sequentially coupled in stages. In such examples, multiple turning inlets 210, 220 are sequentially arranged, with an axial outlet 214 of the first turning inlet 210 being connected to a radial inlet 222 of the second turning inlet 220. Further, in the example of FIG. 2, the first turning inlet 210 includes a radially aligned inlet 212 connected to a source of the process fluid, and the second turning inlet 220 includes an axially aligned outlet 224 connected to a process fluid exhaust. In other examples, any number of sequential turning inlets 210, 220 can be connected in a similar manner to provide an adequate number of sequential devices. Furthermore, in some examples, each of the sequential turning inlets 210, 220 has a substantially identical flow path defining geometry, although interior dimensions, and housing shapes surrounding the geometry may vary. In these multi-stage embodiments, the respective turning inlets 210, 220 are in separate respective housings or in a shared common housing. Further, in some multi-stage embodiments including more than two stages, a subset of stages can be contained in shared housings, while another subset of stages are individually housed. While the two stages in the illustrated multi-stage device are axially offset, it is appreciated that in alternative examples the devices can be axially aligned, such that the stages are coaxial.In yet another variation, the flow through the turning duct can be reversed, allowing for the turning duct to turn an annular axial flow to a radial or angled pipe flow.

[0021] With continued reference to FIGS. 1 and 2, and with reference to FIGS. 3A-3E a geometry of a turning duct 100, such as could be used at the inlet 22 of FIG. 1 and as the sequentially arranged inlets 210, 220 of FIG. 2, is illustrated. FIG. 3A illustrates an isometric view of the geometry, FIG. 3B illustrates a rear view (from the upstream axial end, relative to the axis of the turbine in FIG. 1), FIG. 3C illustrates a side view, FIG. 3D illustrates a top view, and FIG. 3E illustrates a front view (from a downstream end, relative to the axis of the turbine in FIG. 1). Similarly, FIG. 4 illustrates a radially inward facing cross section view drawn along line A-A in FIG. 3A, and FIG. 5 illustrates a side cross sectional view drawn along line B-B in FIG. 3A.

[0022] In one embodiment, the turning duct 100 includes an inlet region 110 disposed along a vertical axis 102 of the inlet duct 100 and receiving a fluid flow 106. The inlet region 110 is generally circular in shape and defines a plane normal to, or approximately normal to, a horizontal axis 104 defined by the turbomachine rotational axis in which the turning duct 100 is included. In alternate examples, the inlet region 110 can be angled, relative to the horizontal axis 104, by between 15 and 100 degrees. In the alternate examples, the degree by which the turning duct 100 redirects the fluid flow 106 is reduced to the corresponding amount, with the reduction being achieved by altering a curvature of a turning region 122. The curvature of the turning region is defined by an interior back wall having a duct curvature of at most 45 degrees. In some examples, the interior surface of the turning duct 100 can be textured across all the flow directing surface, or across a portion of the flow directed surface. The texturing can be configured to turbulate the fluid flow 106 at the surface, thereby preventing fluid drag and providing a more even flowrate throughout the turning duct 100.

[0023] In one embodiment, a flow divider 108 is disposed within the inlet region 110 and extends at least partially radially inward from a perimeter 112 of the inlet region 110 towards the vertical axis 102. In the illustrated example, the flow divider 108 is a bifurcation wedge with a narrowest portion at an upstream end of the flow divider 108 and a wedge portion extending into a bifurcation region 114. An angle 101 or curvature of the wedge portion of the flow divider 108 is chosen to smoothly direct the flow from the upstream portion 124, through the bifurcation region 114 to a first turning region 120 or a second turning region 122. The flow divider 108 splits the fluid flow 106 from the inlet region 110 into two bifurcated flows116, 118, each of which flows into a corresponding turning region 120, 122. In some examples, the flow divider extends at least 50% of a diameter of the inlet region 110.

[0024] In one embodiment, the first turning region 120 and the second turning region 122 are disposed downstream of the bifurcation region 114 and receive the respective bifurcated flows 116, 118 and redirect the bifurcated flows 116, 118 from a first direction oriented along the vertical axis 102 to a second direction oriented along a horizontal axis 104 of the turning duct 100. The turning region 120, 122 includes an upstream portion 124 radially flared away from the perimeter 112 of the inlet region 110. The respective inner walls of the turning regions 120, 122 together define a radially inward opening enclosed by the respective inner walls 140 and aligned along a horizontal axis 104 of the turning duct 100. Within the turning region 120, 122 the bifurcated flow 116, 118 fans out and encircles the horizontal axis 104, with each turning region 120, 122 encircling approximately 50% of the horizontal axis 104.

[0025] In one embodiment, the particular curvature of the turning region 120, 122 is defined by a turning arc within a range of 15-100 degrees, and in some examples of approximately90 degrees. The curvature ensures a smooth and steady transition from radial to axial of the bifurcated flows 116, 118. In one embodiment, a convergence region 126 is disposed downstream of the turning regions 120, 122 and is flared radially inward toward the horizontal axis 104. The convergence region 126 recombines the bifurcated flows 116, 118 into a single recombined flow 130. An annular region 128 is disposed downstream of the convergence region 126 and defines an annular outlet 132 of the turning duct 100. The annular outlet 132 includes an inner wall 140, defining a first radius 150 and an outer wall defining a second radius 152. A ratio of the radius 152 of the external wall 142 to a radius 150 of the inner wall 140 is in the range of 1.05-2. In one particular example, the ratio is approximately 1.5-1. 1.

[0026] Alternatively, this can be expressed as the radius of the inner wall 140 being in a range of 6-48 inches, and the radius 152 of the outer wall being in the range of 6.25-72. The cross sectional area of the outlet, in this example, is JT *rlA2 - *r2A2, where rl is the radius 142 of the external wall 152 and r2 is the radius 150 of the internal wall 140. In some examples, this cross sectional area can be defined as a function of a cross sectional area of the inlet 110, resulting in a defined ratio of inlet to outlet cross sectional areas, thereby providing desired magnitudes of flow acceleration and / or deceleration. In one example, the ratio of the inlet to outlet is less than 2.

[0027] In one embodiment, the bifurcated flows 116 118 are “unwrapped” from the nominal pipe diameter and they, in combination with the remaining semicircular flow volume are directed in a relatively large radius towards the annular inlet portion of the downstream turbomachine. This particular topology allows the flow to follow relatively smooth streamlines with no significant separation or recirculation zones. In addition a smooth, monotonic acceleration of the flow is achieved.

[0028] In one embodiment, the turning duct 100 may be used on a turbomachine heater configuration. Such an example is illustrated in a highly schematic fashion at FIGS. 6A and 6B, with FIG. 6A illustrating an assembled configuration with a turning duct 300 wrapped around a bearing compartment 312 of a turbomachine 310. The inlet portion 322 receives fluid flow with is passed through the body to the outlet 324 and passed to the turbomachine fluid passage.

[0029] This process is used, in one particular aspect, turbomachinery devices to impart thermal energy to a process fluid (e.g., a turboheater). By way of example, this process can be used to thermally decompose (crack) a high molecular weight hydrocarbon to lower molecular weight species. It may be required to use two or more turboheater devices to achieve the desired chemical reaction. In this case the inlet to the second device is part of the quiescent reaction zone where the chemical reaction is occurring after achieving a threshold activation energy via the upstream turboheater device as shown in FIG. 2. When two stages of a turboheater chemical reactor device are required, a downstream reaction zone of a first turboheater also includes the inlet device of the downstream stages. An embodiment with two stages is shown in Figure two showing the invented inlet device.

[0030] While illustrated and described herein as a device that converts an inlet flow normal to the axis into an annular flow about the axis, it will be appreciated that the same device could be used with a reversed fluid flow to turn an annular flow to a normal, or at least partially normal, flow. Further, it is appreciated that specific geometries are necessitated and dependent on the presence of, and associated dimensions of, the device(s) located in the compartment 312 of the turning duct 300.

Claims

CLAIMSWhat is claimed is:

1. A turning duct for a rotating machine comprising: an inlet disposed along a vertical axis of the turning duct, a flow divider disposed within the inlet region extending at least partially radially inward from a perimeter of the inlet towards the vertical axis; a bifurcation region disposed downstream of the inlet region directing the fluid flow into a first bifurcated flow and a second bifurcated flow, a first turning region and a second turning region disposed downstream of the bifurcation region receiving the respective bifurcated flows and redirecting the bifurcated flows from a first direction oriented along the vertical axis to a second direction oriented along a horizontal axis of the inlet duct; a convergence region disposed downstream of the turning regions flared radially inward and directing the bifurcated flows to recombine; and an annular region disposed downstream of the convergence region and disposed about a horizontal axis of the turning duct.

2. The turning duct of claim 1, wherein the inlet region is circular and the flow divider comprises a wedge extending along a radius of the inlet region.

3. The turning duct of claim 2, wherein the wedge extends at least 50% of a diameter of the inlet region.

4. The turning duct of claim 2, wherein the wedge defines a transition angle in the range of 30 to 110 degrees.

5. The turning duct of claim 1, wherein each turning regions comprise an upstream portion radially flared away from the perimeter of the inlet region, wherein respective inner walls of the turning regions together define a radially inward opening.

6. The turning duct of claim 1, wherein the convergence region is configured to combine the bifurcated flows into a recombined flow at an annular outlet of the turning duct.

7. The turning duct of claim 6, wherein the annular outlet of the turning duct is defined by an internal circumference and an external circumference and wherein a ratio of a radius of the external circumference to a radius of the internal circumference is in the range of 1.05 to 2.

8. The turning duct of claim 7, wherein the ratio is approximately 1.05-1.15.9 The turning duct of claim 1 , further including an interior back wall, and wherein the interior back wall defines a duct curvature of at most 45 degrees.

10. The turning duct of claim 1, wherein the first opening defines a first cross sectional area and the second opening defines a second cross sectional area and a ratio of the first cross sectional area to the second cross sectional area is less than 2 and wherein the second cross sectional area is defined by JT *rlA2 - n *r2A2, where rl is a radius of an external wall of the second opening and r2 is a radius of an internal wall of the second opening.

11. A method for providing a process fluid to a rotary machine, the method comprising: receiving the process fluid at an inlet of a turning duct; bifurcating the process fluid using a flow divider and providing a first portion of the process fluid to a first turning region and a second portion of the process fluid to a second turning region; turning the respective portions of the process fluid from a radial direction to an axial direction, relative to an axis defined by an annular outlet; and outputting the process fluid through the annular outlet in an axial direction.

12. The method of claim 11 , wherein bifurcating the process fluid at the inlet of the turning duct comprises providing the fluid to a bifurcation wedge extending across at least a portion of the inlet, and wherein the bifurcation between the first portion and the second portion is approximately even.

13. The method of claim 11 , further comprising combining the process fluid using a convergence region downstream of the first turning region and the second turning region.

14. A rotary machine comprising: a rotary machine defining an axis and including at least one momentum exchange device configured to drive or be driven by a process fluid through a process fluid flowpath; the process fluid flowpath comprising a turning duct having a first opening and a second opening, with the first opening being angled relative to the axis by at least 15 degrees, relative to the axis, and the second opening being axially aligned relative to the axis, the second opening radially surrounding a portion of the turbo-machine; and wherein the turning duct defines an internal flowpath, and includes a bifurcation wedge aligned with the first opening, the bifurcation wedge bifurcating the internal flowpath into a first portion and a second portion, the first portion defining a flow in a first direction about the axis and the second portion defining a flow in a second direction about the axis, the second direction being opposed to the first direction.

15. The rotary machine of claim 14, wherein the first opening is angled relative to the axis by approximately 90 degrees.

16. The rotary machine of claim 15, wherein the second opening is defined by an internal circumference and an external circumference and wherein a ratio of a radius of the external circumference to a radius of the internal circumference is in the range of 1.05-2.

17. The rotary machine of claim 16, wherein the ratio is approximately 1.05-1.15.

18. The rotary machine of claim 14, further comprising a bifurcation wall extending axially from the bifurcation wedge such that the fluid flowpath is bifurcated at the bifurcation wedge.

19. The rotary machine of claim 13, further including a second turning duct defining a flowpath having a shape substantially identical to the internal flowpath of the first turning duct and wherein a first opening of the second turning duct is fluidly connected to the second opening of the first turning duct.

20. The rotary machine of claim 13, wherein the rotary machine is a turboheater.

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