Entry mixing elements and related static mixers and methods of mixing

An entry mixing element is provided for mixing an incoming fluid flow having first and second unmixed components arranged so as to define a transverse flow cross-section perpendicular to a flow direction. The entry mixing element includes a central axis configured to be aligned with the flow direction of the incoming fluid flow, and an entry dividing wall extending parallel to the central axis and positioned to divide the incoming fluid flow into first and second fluid flow portions, each portion containing an amount of the first component and an amount of the second component. The entry dividing wall is configured to divide the incoming fluid flow into the first and second fluid flow portions in any rotational orientation of the entry mixing element about its central axis relative to the transverse flow cross-section of the incoming fluid flow. Related static mixers and methods of mixing are also provided.

TECHNICAL FIELD

This disclosure generally relates to fluid dispensers, and more particularly, to static mixers and methods of mixing multi-component fluid flows.

BACKGROUND

A variety of static mixer types exist for mixing together multiple components of a fluid flow received from fluid cartridges, such as side-by-side fluid cartridges, or similar dispensing devices. Generally, conventional mixers mix the components of the fluid flow together by continuously dividing and recombining the components in an overlapping manner. This mixing is achieved by directing the fluid components along a mixing component structure that includes a series of mixing elements (also referred to as “mixing baffles”) of alternating geometry. Such division and recombination creates alternating layers of the fluid components. In this manner, the streams of the fluid components are progressively thinned and diffused, thereby creating a generally homogenous mixture of the fluid components at the mixer outlet. While such mixers are generally effective to mix a majority of the mass of the incoming fluid components, mixers are often subject to a streaking phenomenon in which streaks of one of both of the fluid components are left completely unmixed in the final mixture extruded at the mixer outlet.

The mixing element arranged at the inlet end of a mixer is generally referred to as an entry mixing element, or initial mixing element, and it provides some initial division of the incoming fluid flow directed into the static mixer. The effectiveness of conventional entry mixing elements in providing a degree of initial mixing sufficient to mitigate streaking is dependent upon proper rotational alignment of the entry mixing element relative to a transverse flow cross-section of the incoming fluid flow. For example,FIG. 1Ashows a conventional mixing component1and its entry mixing element2positioned in a non-optimal rotational orientation relative to a transverse flow cross-section of an incoming fluid flow containing fluid component3(the other component(s) not being shown). As shown inFIG. 1A, the fluid component3is not fully divided by the entry mixing element2, thereby resulting in undesired streaking of the fluid component3in the mixture extruded at the mixer outlet. By comparison,FIG. 1Bshows the mixing component1and its entry mixing element2positioned in an optimal rotational orientation relative to a transverse flow cross-section of the incoming fluid flow, such that fluid component3is divided into at least first and second portions and streaking in the extruded mixture is thereby substantially averted.

For many static mixers, the mixer conduit includes an integrally formed nut for threadedly attaching the mixer to a fluid cartridge or similar dispensing device. As the mixer is threaded onto the cartridge, the mixing component often rotates with the mixer conduit relative to the cartridge. Thus, the final rotational orientation of the mixing component relative to the fluid outlets of the cartridge, and thus to a transverse flow cross-section of the fluid flow to be mixed, is dependent on the degree to which the user tightens the mixer onto the cartridge. Different users, or even the same user, may rotate a particular mixer to inconsistent final rotational orientations when tightening the mixer. Consequently, and undesirably, mixing performance of the entry mixing element may vary significantly from user to user, and even from use to use by the same user.

Accordingly, there is a need for improvements to known entry mixing elements and corresponding static mixers that address these and other shortcomings of known entry mixing elements and static mixers.

SUMMARY

In an exemplary embodiment of the invention, an entry mixing element is provided for mixing an incoming fluid flow having first and second unmixed components arranged so as to define a transverse flow cross-section perpendicular to a flow direction of the incoming fluid flow. The entry mixing element includes a central axis configured to be aligned with the flow direction of the incoming fluid flow, and an entry dividing wall extending parallel to the central axis. The entry dividing wall is positioned to divide the incoming fluid flow into a first fluid flow portion and a second fluid flow portion, each of the first and second fluid flow portions containing an amount of the first component and an amount of the second component. Advantageously, the entry dividing wall is configured to divide the incoming fluid flow into the first and second fluid flow portions in any rotational orientation of the entry mixing element about its central axis relative to the transverse flow cross-section of the incoming fluid flow.

In another exemplary embodiment of the invention, a method is provided for mixing first and second components of a fluid flow with a static mixer including a mixer conduit and a mixing component having an entry mixing element and a plurality of mixing baffles arranged downstream of the entry mixing element. The method includes introducing the fluid flow having first and second components into an inlet end of the mixer conduit, the first and second components being arranged so as to define a transverse flow cross-section perpendicular to a flow direction of the fluid flow. The method further includes forcing the fluid flow into contact with the entry mixing element. More specifically, the fluid flow is divided with an entry dividing wall into a first fluid flow portion and a second fluid flow portion, each of the first and second fluid flow portions containing an amount of the first component and an amount of the second component. Subsequently, the first and second fluid flow portions are recombined to form a mixture of the first and second components. The mixture is directed downstream of the entry mixing element to be mixed further by the mixing baffles. Advantageously, the entry mixing element is configured to divide the fluid flow into the first and second fluid flow portions in any rotational orientation of the entry mixing element about its central axis relative to the transverse flow cross-section of the fluid flow.

Various additional features and advantages of the invention will become more apparent to those of ordinary skill in the art upon review of the following detailed description of one or more illustrative embodiments taken in conjunction with the accompanying drawings.

DETAILED DESCRIPTION

Referring toFIGS. 2 and 3, a static mixer10according to an exemplary embodiment of the invention is shown. The static mixer10includes a mixing component12having a series of mixing elements (or “baffles”) for dividing, shifting, and recombining multiple components of an incoming fluid flow F in various manners along a length of the static mixer10. These various mixing elements function together to thoroughly mix the multiple components of the fluid flow F, and thereby minimize streaks of unmixed fluid components in the fluid mixture extruded at an outlet20of the mixer10.

The static mixer10includes an outer conduit14in which the mixing component12is received. The conduit14defines an inlet end socket16configured to be attached to a cartridge, cartridge system, or metering system (none of which are shown) containing at least two fluid components to be mixed together. For example, the inlet end socket16may be connected to any of the two-component cartridge systems made available by Nordson Corporation. The conduit14includes a body section18shaped to receive the mixing component12, and a nozzle outlet20extending from the body section18. Although the body section18and mixing component12are shown as having substantially square cross-sectional profiles, those skilled in the art will appreciate that various alternative cross-sectional shapes may also be suitable, such as circular or generally rounded, for example.

The series of mixing elements of the mixing component12begins with an entry mixing element22arranged adjacent to the inlet end socket16to contact the incoming fluid flow F as it is directed into the static mixer10. The multiple, unmixed components of the incoming fluid flow F are arranged so as to define a transverse flow cross-sectional perpendicular to a flow direction of the fluid flow, as shown inFIG. 9A, for example. Advantageously, the entry mixing element22ensures some initial division and mixing of each of the multiple components of the fluid flow F regardless of the rotational orientation of the entry mixing element22, about a central axis of the mixing component12, relative to the transverse flow cross-section of the incoming fluid flow F.

The mixing component12further includes a series of mixing baffles24arranged downstream of the entry mixing element22, shown in the form of alternating left-handed and right-handed versions (labeled24Land24R, respectively). Each double wedge mixing baffle24functions to divide the fluid flow at a leading edge of the mixing baffle24, and then shift or rotate the flow clockwise or counterclockwise through a partial rotation before expanding and recombining the fluid flow at a trailing edge of the mixing baffle24.

The mixing component12may further include one or more flow shifter elements26, for example arranged after each set of several double wedge mixing baffles24in the series of mixing elements. The flow shifter element26is configured to shift at least a portion of the fluid flow from one side of the conduit14to another side of the conduit14, thereby providing a different type of fluid movement and mixing contrasting with the double wedge mixing baffles24.

FIGS. 3-6show a partial portion of the exemplary mixing component12, separated from the remainder of the static mixer10. The series of mixing elements and baffles22,24,26defining the mixing component12are integrally molded with one another so as to define first and second sidewalls28,30of the mixing component12. The first and second sidewalls28,30at least partially bound opposite sides of the mixing component12, whereas the other sides of the mixing component12extending between the first and second sidewalls28,30remain largely open or exposed to an associated interior surface32of the conduit14(one of the interior surfaces is cut away and not shown inFIG. 2). The total quantity of mixing elements24,26may vary in different embodiments of the mixer10. Moreover, it will be understood that the static mixer10is merely an exemplary mixer in which the entry mixing element22is implemented.

Referring toFIGS. 6-8, features of the entry mixing element22are shown in greater detail. The entry mixing element22advantageously provides initial division and mixing of each of first and second fluid components of the incoming fluid flow F in every possible rotational orientation of the entry mixing element22, about a central axis of the static mixer10, relative to the transverse flow cross-section of the incoming fluid flow F. In order words, the entry mixing element22is effective to provide this initial division and mixing regardless of the degree to which the static mixer10is threaded onto a fluid cartridge (not shown) or similar dispensing device from which the fluid flow F is directed.

As described in greater detail below, the entry mixing element22mixes the incoming fluid flow F by dividing the fluid flow F into at least first and second fluid flow portions, each containing an amount of the unmixed first and second components of the incoming fluid flow F. The entry mixing element22then recombines the first and second fluid flow portions and directs the mixture downstream to be mixed further by additional mixing elements, such as mixing baffles24and flow shifter elements26. In this manner, the initially unmixed components of the incoming fluid flow F are sufficiently mixed to form a homogenous mixture by the time they reach the mixer outlet, and undesirable streaking of one or both of the fluid components in the extruded mixture is substantially prevented.

It will be appreciated that the orientation-based labels used below, such as “vertical,” “horizontal,” “left,” “right,” “top,” “bottom,” “upper,” “lower,” “upward,” “downward,” and similar terms, as used in reference to elements of the exemplary embodiments shown in the Figures, are for illustrative purposes only and refer to the exemplary orientations of these elements as shown in the Figures. Further, it will be appreciated that the embodiments shown may be oriented in a variety of alternative orientations that are encompassed within the scope of this disclosure. Accordingly, the orientation-based labels used herein are not intended to limit the scope of the invention to any particular orientation of the embodiments.

As shown best inFIGS. 6-8, the entry mixing element22includes an entry dividing wall34that extends in a generally horizontal direction and includes a leading edge36that faces the incoming fluid flow F, a trailing edge38, a planar upper surface40, and an opposed planar lower surface (not shown). The leading edge36is defined by a left front angled surface42that extends angularly downward from the upper surface40, and further by a right front angled surface44that extends angularly upward from the bottom surface. The trailing edge38is defined by first and second hook sections46,48, described in greater detail below.

The entry mixing element22further includes a planar front panel50defining a planar front surface52that extends vertically and generally transverse to the entry dividing wall34and to a longitudinal axis of the mixer10. The front panel50includes an upper front panel portion54extending primarily in the upper right quadrant of the entry mixing element22, and an integrally formed lower front panel portion56extending primarily in the lower left quadrant of the entry mixing element22. The upper front panel portion54defines a top58and a right side60of the entry mixing element22, and the lower front panel portion56defines a bottom62and a left side64of the entry mixing element22.

The upper and lower front panel portions54,56are formed with similar constructions, each including a body66and a leg68extending therefrom. The leg68of the upper front panel portion54extends downwardly into the lower right quadrant, while the leg68of the lower front panel portion56extends upwardly into the upper left quadrant. Each of the legs68includes a wedge70that projects outwardly from the respective right and left sides60,64of the entry mixing element22. As shown inFIG. 6, the wedges70project outwardly beyond the sides of the mixing baffles24located downstream of the entry mixing element22.

An upper fluid gate72is defined in the upper left quadrant of the planar front panel50between the body66of the upper front panel portion54and the leg68of the lower front panel portion56. A lower fluid gate74is defined in the lower right quadrant between the body66of the lower front panel portion56and the leg68of the upper front panel portion54.

As shown best inFIG. 6, the planar front panel50of the mixing element22is formed with a height H defined by the perpendicular distance between the top58and the bottom62. Further, the planar front panel50is formed with a width W defined by the perpendicular distance between the right side60and left side64. As shown, the entry mixing element22may be formed such that its height H is less than its width W, thereby defining an imaginary outer periphery having a non-square rectangular shape. Moreover, the width W may be generally equal to a corresponding width of at least the immediately downstream mixing baffle24. Further, the height H may be less than a corresponding height of at least the immediately downstream mixing baffle24. This height differential defines an upper fluid slot76extending laterally across the top58of the entry mixing element22and opening laterally to the upper fluid gate72, and a lower fluid slot78extending laterally across the bottom62of the entry mixing element22and opening laterally to the lower fluid gate74.

It will be appreciated that the entry mixing element22may be formed with a height H and a width W having various alternative relationships with one another, and with the corresponding height and width of the immediately downstream mixing baffle24, suitable to define first and second fluid slots similar to the upper and lower fluid slots76,78shown and described herein.

As best shown inFIG. 8, a downstream side of the upper front panel portion54defines an upper deflecting surface80extending vertically upward from the upper surface40of the entry dividing wall34. Similarly, a downstream side of the lower front panel portion56defines a lower deflecting surface82extending vertically downward from the lower surface of the entry dividing wall34. Each of the deflecting surfaces80,82includes first and second planar surfaces84,86oriented at different angles relative to the fluid flow, the second planar surface86being oriented at a sharper angle to the fluid flow than the first planar surface84.

Having described the structural features of the exemplary entry mixing element22, directional movements imparted by the entry mixing element22on an incoming two-component flow F directed into the static mixer10will now be described.

As the fluid flow F is introduced into the static mixer10through the inlet16of the conduit14, the fluid flow F contacts the planar front surface52of the entry mixing element22. The fluid flow F is then divided horizontally by the leading edge36of the entry dividing wall34, and vertically by the inner edges of the front panel portion bodies66, into an upper fluid flow portion and a lower fluid flow portion, each containing an amount of each of the components of the original incoming fluid flow F. For example, the upper fluid flow portion may contain a first amount of the first component of the fluid flow F and a first amount of a second component of the fluid flow F. Meanwhile, the lower fluid flow portion may contain a second amount of the first component, and a second amount of the second component. Accordingly, each of the components of the incoming fluid flow F is divided by the entry mixing element22. As described above, the unique structural configuration of the entry mixing element22enables similar division of the incoming fluid flow components regardless of the rotational orientation of the mixing component12, and its entry mixing element22, relative to the transverse flow cross-section of the incoming fluid flow F.

The upper fluid flow portion is then compressed and directed through the upper fluid gate72and the upper fluid slot76, while the lower fluid flow portion is compressed and directed through the lower fluid gate74and the lower fluid slot78. While passing through the upper fluid gate72, the upper fluid flow portion flows across the upper surface40of the entry dividing wall34and expands laterally to contact the upper deflecting surface80. Simultaneously, while passing through the lower fluid gate74, the lower fluid flow portion flows across the lower surface of the entry dividing wall34and expands laterally to contact the lower deflecting surface82.

After expanding laterally, the upper and lower fluid flow portions advance toward the trailing edge38of the entry dividing wall34. The first hook section46guides the lower fluid flow portion upwardly, and the second hook section48guides the upper fluid flow portion downwardly, thereby recombining the upper and lower fluid flow portions. The recombined fluid flow then advances downstream toward the mixing baffles24for further mixing.

Advantageously, the upper and lower fluid slots76,78defined by the entry mixing element22increase an exposure of the fluid flow to upper and lower dividing hook sections88,90, or similar fluid dividing elements, formed on the leading edge of a mixing baffle24arranged downstream, as best inFIGS. 3 and 6. More specifically, the upper fluid slot76is aligned with and directs the upper fluid flow portion toward an outer tip of the upper hook section88, and lower fluid slot78is aligned with and directs the lower fluid flow portion toward an outer tip of the lower hook section90. This direct exposure of the upper and lower fluid flow portions to the hook sections88,90of the downstream mixing baffle24enables enhanced mixing of the first and second fluid components downstream of the entry mixing element22, and thereby reduces the undesirable streaking effect described above.

In illustration of the general flow description provided above,FIGS. 9A-9Dschematically show a series of flow cross-sections taken for a sample fluid flow directed through the mixing component12of the static mixer10. The flow cross-sections are taken generally transverse to a flow direction of the fluid flow. The sample fluid flow shown has a 1:1 volume ratio of first and second fluid components A, B. The specific locations along the mixing component12at which the flow cross sections are taken are indicated inFIG. 3. To that end,FIGS. 9A and 9Bshow flow cross sections corresponding to positions along the entry mixing element22, whileFIGS. 9C and 9Dshow flow cross sections corresponding to positions along the mixing baffles24arranged downstream of the entry mixing element22.

As shown inFIG. 9A, and as represented in phantom inFIG. 3, the two fluid components A, B of the incoming fluid flow are unmixed as they approach the front panel50of the entry mixing element22.FIG. 9Bshows the fluid flow after having been divided by the entry dividing wall34and the planar front panel50into upper and lower fluid flow portions, and now passing through the upper and lower fluid gates72,74and the upper and lower fluid slots76,78. In particular, component A is divided to pass through the upper fluid gate72and the lower fluid slot78, while component B is divided to pass through the lower fluid gate74and the upper fluid slot76. Accordingly, each of the fluid flow components A, B has been divided by the entry mixing element22into upper and lower flow portions.

Based on the exemplary rotational orientation of the mixing component12relative to the two fluid components A, B shown in the Figures, it will be evident to those skilled in the art that the entry mixing element22is effective to divide each of the components A, B into at least first and second portions regardless of the rotational orientation of the mixing component12relative to the transverse flow cross-section defined by the components A, B. Moreover, while the sample fluid flow ofFIGS. 9A-9Dis shown having a 1:1 volume ratio of component A to component B, it will be appreciated that the mixing component12, including the entry mixing element22, will similarly mix fluid flows having various alternative volume ratios of first and second components, ranging from 1:1 up to and including 10:1, for example. The same will be appreciated for the alternative embodiments described herein.

As the initially mixed fluid flow advances downstream from the entry mixing element22, it is mixed further by the mixing baffles24so as to progressively increase the quantity of layers of components A, B in the fluid flow portions, and simultaneously decrease the thickness of each layer, as illustrated inFIGS. 9C and 9D, for example. In this manner, the two fluid components A, B are mixed together to form a generally homogenous mixture to be extruded from the static mixer10without streaks of unmixed fluid components.

Additional mixing elements according to exemplary alternative embodiments of the invention are described below in connection withFIGS. 10-24. Similar to the entry mixing element22, each of the exemplary alternative mixing elements ensures some initial division and mixing of each of the multiple components of an incoming fluid flow, regardless of the rotational orientation of the entry mixing element, about a central axis of the mixing component, relative to a transverse flow cross-section of the incoming fluid flow. More specifically, regardless of the rotational orientation of the entry mixing element relative to the flow cross-section, an entry dividing wall of the entry mixing element divides the incoming fluid flow into an inner fluid flow portion and an outer fluid flow portion that surrounds the inner fluid flow portion. Each of the inner and outer fluid flow portions contains an amount of the first fluid component of the incoming fluid flow, and an amount of the second fluid component of the incoming fluid flow.

Referring toFIGS. 10-14, a mixing component100having an entry mixing element102according to another exemplary embodiment of the invention is shown. The entry mixing element102includes an entry dividing wall104that extends along an axial direction of the mixing component100, and circumferentially so as to divide in the incoming fluid flow F into an inner fluid flow portion and an outer fluid flow portion that surrounds the inner fluid flow portion.

The entry dividing wall104defines an opening106through which the inner fluid flow portion is directed. The entry dividing wall104may be formed so as to define the opening106with a closed cross-sectional shape. Accordingly, the entry dividing wall104fully surrounds the inner fluid flow portion, and fully separates the inner fluid flow portion from the outer fluid flow portion. As shown inFIGS. 10-14, the entry dividing wall104may be formed with a cross-section having a generally reverse-D shape, thereby providing the opening106with a similar shape. As shown best inFIGS. 10 and 13, the entry dividing wall104may extend from an inlet end of the mixing component100such that a center of the opening106is laterally offset from a central axis of the mixing component100and a corresponding axial center of the entry mixing element102.

The entry dividing wall104projects axially outward from a back wall108of the entry mixing element, the back wall108being formed integrally with, or otherwise coupled to, a downstream mixing baffle24. The back wall108is formed primarily at the left half of the entry mixing element102and extends radially outward from the entry dividing wall104so as to define a left side110, a top112, and a bottom114of the entry mixing element102. The entry dividing wall104defines a right side116of the entry mixing element102. The back wall108includes a planar portion118extending laterally inward from the left side110toward the axial center of the entry mixing element102, and a curved portion120extending from the planar portion118in the downstream direction. The planar and curved portions118,120of the back wall108are positioned to deflect the outer fluid flow portion in the downstream direction.

An inner deflecting wall122joins upper, lower, and right-side portions of the entry dividing wall104, and may be rounded at the junctions of these dividing wall portions to funnel the inner fluid flow portion through an inner passage124that extends through the back wall108. The inner deflecting wall122and an inner surface of the entry dividing wall104may be shaped so as to form the inner passage124with a generally reverse D-shape as well.

In use, referring primarily toFIGS. 11-14, an incoming fluid flow having first and second fluid components is directed toward the entry mixing element102, and is divided by the entry dividing wall104into an inner fluid flow portion and an outer fluid flow portion that surrounds the inner fluid flow portion. More specifically, the incoming fluid flow is divided such that each of the inner fluid flow portion and the outer fluid flow portion contains an amount of the first fluid component and an amount of the second fluid component.

The inner fluid flow portion passes through the opening106of the entry dividing wall104and toward the inner passage124. A section of the inner fluid flow portion may contact the inner deflecting wall122, the inner curvature of which funnels the inner fluid flow portion toward and through the inner passage124. Simultaneously, the outer fluid flow portion passes outwardly of the entry dividing wall104, so as to surround the inner fluid flow portion. A section of outer fluid flow portion may contact the planar and curved portions118,120of the back wall108, which deflect the outer fluid flow portion inwardly toward a central axis of the mixing component100, and downstream. At the downstream side of the entry mixing element102, shown inFIGS. 12 and 14, the inner and outer fluid flow portions are recombined before passing to a downstream mixing baffle24for further mixing.

Referring toFIGS. 15A and 15B, the entry mixing element102is shown in first and second exemplary rotational orientations, respectively, relative to a transverse flow cross-section of an incoming fluid flow. The fluid flow is shown having a 1:1 component volume ratio of first and second fluid components, the first fluid component (labeled A) shown in shading. The second fluid component may occupy at least a majority of the flow cross-section not occupied by the first component (see, e.g.,FIG. 9A). As shown inFIGS. 15A and 15B, regardless of the rotational orientation of the entry mixing element102relative to the transverse flow cross-section, the entry dividing wall104divides each of the first and second fluid components between the inner fluid flow portion and the outer fluid flow portion.

Referring toFIGS. 15C-15F, the entry mixing element102is shown in four exemplary rotational orientations relative to a transverse flow cross-section of an incoming fluid flow. The fluid flow is shown having a 10:1 component volume ratio of first and second fluid components, the first component (labeled A) shown in shading. Again, regardless of the rotational orientation of the entry mixing element102relative to the transverse flow cross-section, the entry dividing wall104divides each of the first and second fluid components between the inner fluid flow portion and the outer fluid flow portion.

Referring toFIGS. 16-21, a mixing component130having an entry mixing element132according to another exemplary embodiment of the invention is shown. Similar to entry mixing element102ofFIGS. 10-15F, entry mixing element132includes an entry dividing wall134that extends along an axial direction of the mixing component130, and circumferentially so as to divide the incoming fluid flow F into an inner fluid flow portion and an outer fluid flow portion that surrounds the inner fluid flow portion.

As shown best inFIGS. 17 and 18, the entry dividing wall134is generally annular and projects axially outward from a back wall structure136. The entry dividing wall134includes a generally annular outer dividing wall section138and a generally annular inner dividing wall section140positioned radially inward of and surrounded by the outer dividing wall section138. The inner dividing wall section140defines a circular central opening142that directs fluid toward a horizontal dividing panel144and a vertical dividing panel146extending from the back wall structure136, as shown best inFIGS. 18 and 19. The vertical dividing panel146includes upper and lower hook sections148,150that extend angularly in an upstream direction to define a leading edge of the vertical dividing panel146. In an embodiment, the vertical dividing panel146and its hook sections148,150may be formed integrally with a downstream mixing baffle24, as shown inFIG. 16.

An upper fluid gate152extends radially inward through an upper left quadrant of the back wall structure136and the entry dividing wall134, and opens to the central opening142. Similarly, a lower fluid gate154extends radially inward through a lower right quadrant of the back wall structure136and the entry dividing wall134, and opens to the central opening142. Each of the upper and lower fluid gates152,154may taper in width as the fluid gate152,154approaches the central opening142. Consequently, the upper and lower fluid gates152,154divide the back wall structure136and the entry dividing wall134into a left portion156and a right portion158, joined together by the horizontal and vertical dividing panels144,146at the downstream side of the entry mixing element132, as shown inFIGS. 18-20.

As shown best inFIGS. 17 and 18, the back wall structure136is shaped to impart a clockwise rotation to the outer fluid flow portion, and the entry dividing wall134is shaped to impart a counter-clockwise rotation to an outer section of the inner fluid flow portion. More specifically, the back wall structure136includes a first outer baffle160formed on the left portion156of the entry mixing element132, and a second outer baffle162formed on the right portion158of the entry mixing element132. The outer baffles160,162are each sloped to deflect the outer fluid flow in a clockwise rotational direction, as indicated by directional arrows inFIG. 18.

The entry dividing wall134is formed with a first inner baffle164that extends annularly between the inner dividing wall section140and the outer dividing wall section138on the left portion156of the entry mixing element132. A second inner baffle166extends annularly between the inner dividing wall section140and the outer dividing wall section138on the right portion158of the entry mixing element132. The inner baffles164,166are each sloped to deflect an outer section of the inner fluid flow portion in a counter-clockwise rotational direction, as indicated by directional arrows inFIG. 18. As described above, the innermost section of the inner fluid flow portion passes unimpeded through the central opening142defined by the inner dividing wall section140, until it contacts the horizontal and vertical dividing panels144,146at the downstream side of the entry mixing element132.

FIGS. 20 and 21show top and right side views, respectively, of the entry mixing element132, and illustrate additional structural details of the entry dividing wall134and the back wall structure136, described above. For example, as shown inFIG. 20, the leading edge of the vertical dividing panel146, defined by the upper and lower hook sections148,150, may be positioned downstream of a leading edge of the horizontal dividing panel144.

In use, referring primarily toFIGS. 17-19, an incoming fluid flow having first and second fluid components is directed toward the entry mixing element132. The incoming fluid flow is divided by the outer dividing wall section138into an inner fluid flow portion that passes radially inward of the outer dividing wall section138, and an outer fluid flow portion that passes radially outward of the outer dividing wall section138and surrounds the inner fluid flow portion. Each of the inner and outer fluid flow portions has an amount of the first fluid component and an amount of the second fluid flow component.

The inner dividing wall section140further divides the inner fluid flow portion into an outer fluid section that passes between the inner and outer dividing wall sections138,140, and an innermost fluid section that passes radially inward of the inner dividing wall section140, through the central opening142. The outer fluid section is then deflected in a counter-clockwise direction by the first and second inner baffles164,166. More specifically, the first inner baffle164directs a corresponding portion of the outer fluid section toward and through the lower fluid gate154, and the second inner baffle166directs a corresponding portion of the outer fluid section toward and through the lower fluid gate154. Simultaneously, the innermost fluid section of the inner fluid flow portion passes unimpeded through the central opening142, and may be at least partially recombined with the outer fluid section at a location upstream from the horizontal and vertical dividing panels144,146.

While the inner fluid flow portion of the fluid flow is being directed as generally described above, the outer fluid flow portion is deflected in a clockwise direction by the first and second outer baffles160,162. More specifically, the first outer baffle160directs a corresponding portion of the outer fluid flow portion toward and through the upper fluid gate152, and the second outer baffle162directs a corresponding portion of the outer fluid flow portion toward and through the lower fluid gate154. Consequently, the outer fluid flow portion may be recombined at least in part with at least the outer section of the inner fluid flow portion, at a location upstream from the horizontal and vertical dividing panels144,146.

While the entry mixing element132is shown and described as imparting a clockwise rotation to the outer fluid flow portion and a counter-clockwise rotation to the inner fluid flow portion, it will be appreciated that the inner and outer baffles160,162,164,166may be shaped so as to impart various alternative rotational effects on the fluid flow portions.

As the inner and outer fluid flow portions are directed downstream through the upper and lower fluid gates152,154through the central opening142, as generally described above, at least the innermost fluid section of the inner fluid flow portion may be further divided into upper and lower portions by the horizontal dividing panel144. The upper portion may be further divided vertically by the upper hook section148of the vertical dividing panel146, and the lower portion may be further divided vertically by the lower hook section150of the vertical dividing panel146. The mixture of various fluid flow portions flowing downstream from the entry mixing element132is then mixed further by the mixing baffles24of the mixing component130.

Referring toFIGS. 22A and 22B, the entry mixing element132is shown in first and second exemplary rotational orientations, respectively, relative to a transverse flow cross-section of an incoming fluid flow. The fluid flow is shown having a 1:1 component volume ratio of first and second fluid components, the first component (labeled A) shown in shading. The second fluid component may occupy at least a majority of the flow cross-section not occupied by the first fluid component (see, e.g.,FIG. 9A). As shown inFIGS. 22A and 22B, regardless of the rotational orientation of the entry mixing element132relative to the transverse flow cross-section, the outer dividing wall section138divides each of the first and second fluid components between the inner fluid flow portion and the outer fluid flow portion, as described above.

Referring toFIGS. 22C-22F, the entry mixing element132is shown in four exemplary rotational orientations relative to a transverse flow cross-section of an incoming fluid flow. The fluid flow is shown having a 10:1 component volume ratio of first and second fluid components, the first component (labeled A) shown in shading. Again, regardless of the rotational orientation of the entry mixing element132relative to the transverse flow cross-section, the entry dividing wall134divides each of the first and second fluid components between the inner fluid flow portion and the outer fluid flow portion.

It will be appreciated that the relative sizing of various features of the entry mixing element132may be varied in alternative embodiments. For example,FIGS. 23 and 24show a mixing component170having an entry mixing element172according to an exemplary alternative embodiment in which the relating sizing of certain features of the entry mixing element172differs from that of entry mixing element132. In that regard, the entry mixing element172is largely similar in structure to entry mixing element132, as indicated by use of similar reference numerals, except as otherwise described below.

Most notably, the entry dividing wall174of entry mixing element172includes an inner dividing wall section176formed with a generally smaller diameter than the inner dividing wall section140of entry mixing element132. Consequently, a ratio of the outer dividing wall section diameter to the inner dividing wall section diameter is larger for entry mixing element172than for entry mixing element132. To that end, in an exemplary embodiment a dividing wall diameter ratio for entry mixing element172may be approximately 2.1:1, while a corresponding dividing wall diameter ratio for the entry mixing element132may be approximately 1.7:1. As a result, a radial width of the first and second inner baffles178,180of entry mixing element172is larger than a corresponding radial width of first and second inner baffles164,166of entry mixing element132, as will be appreciated upon comparison ofFIGS. 18 and 24, for example.

Additionally, the upper and lower fluid gates182,184of the entry mixing element172may be formed with smaller circumferential widths than upper and lower fluid gates152,154of entry mixing element132. Consequently, the first and second inner baffles178,180of the entry mixing element172are formed with larger circumferential lengths than inner baffles164,166of entry mixing element132, as will be appreciated upon comparison ofFIGS. 18 and 24, for example.

While the present invention has been illustrated by the description of specific embodiments thereof, and while the embodiments have been described in considerable detail, it is not intended to restrict or in any way limit the scope of the appended claims to such detail. The various features discussed herein may be used alone or in any combination. Additional advantages and modifications will readily appear to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus and methods and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the scope of the general inventive concept.