Patent Publication Number: US-2022220983-A1

Title: Apparatuses and methods for de-aeration of a liquid

Description:
FIELD OF THE DISCLOSURE 
     The present disclosure relates generally to reservoir deaeration. 
     BACKGROUND OF THE DISCLOSURE 
     Gases, such as air, are removed from liquid flows, such as coolants, lubricants, or hydraulic fluids, in order to improve performance of the liquids and associated machinery. For example, removing gases from a flow of coolant enhances the cooling performance of the coolant. Because gases are compressible, removal of the gases also improves the ability to pump the liquid. Further, entrained gases can lead to erosion of equipment components. 
     SUMMARY OF THE DISCLOSURE 
     A first aspect of the present disclosure is directed to a reservoir for a hydraulic system. The hydraulic system may include a housing that includes a floor and defining a cavity; a baffle disposed in the cavity and dividing the cavity into a first portion and a second portion; and an inlet conduit extending into the first portion of the cavity. The baffle and the floor may define an acute angle. The inlet may include a longitudinal axis. The reservoir may also include a diffusion chamber. The diffusion chamber may include a wall and a first plurality of apertures formed in a portion of the wall of the diffusion chamber. The portion of the wall may extend along less than an entire perimeter of the wall. The reservoir may also include an outlet in fluid communication with the second portion of the cavity. The baffle may include a first portion extending in a first direction from the diffusion chamber; a second portion extending in a second direction from the diffusion chamber; and a second plurality of apertures formed in the second portion of the baffle. The first plurality of apertures may open towards the first portion of the baffle. The second set of apertures may provide fluid communication between the first portion of the cavity and the second portion of the cavity. 
     A second aspect of the present disclosure is directed to a method of de-aerating a liquid. The method may include flowing a liquid into a cavity of a reservoir, the reservoir comprising a baffle disposed in the cavity, the baffle comprising a first portion that is oriented at an angle relative to a floor of the reservoir; impinging the fluid flow onto a portion of a first side of the baffle that extends along the first portion of the baffle; conducting the fluid flow through a first plurality of apertures into a first portion of the cavity of the reservoir towards a first side of the reservoir; and generating turbulence in the fluid as the fluid exits the plurality of apertures to release a gas entrained in the fluid. 
     The various aspects may of the present disclosure include one or more of the following features. The diffusion chamber may extend to the baffle, and the baffle may partially enclose the diffusion chamber. The second plurality of apertures may include a plurality of slots. The plurality of slots may be arranged in a plurality of rows. The slots in adjacent rows of the plurality of rows may be offset from each other. The portion of the wall of the diffusion chamber in which the first plurality of apertures is formed may be defined by a spread angle having a vertex lying on the longitudinal axis. The spread angle may be within a range of 30° and 180°. The acute angle defined between the baffle and the floor is within a range of 30° and 45°. The second portion of the baffle may be offset from the floor by a greater extent than the first portion of the baffle is offset from the floor. A seal may be formed between the diffusion chamber and the inlet conduit. The diffusion chamber may define an interior cavity, and the wall of the diffusion chamber may extend beyond the interior cavity. 
     The various aspects of the present disclosure may also include one or more of the following features. The reservoir may also include a diffusion chamber disposed in the cavity, and the first portion of the baffle may form a portion of the enclosure of the diffusion chamber. The first plurality of apertures may be formed in a portion of a wall of the diffusion chamber. The portion of the wall in which the first plurality of apertures is formed may be defined by a spread angle having a vertex along a longitudinal axis of the diffusion chamber. Flowing a liquid into a reservoir may include flowing the fluid into the diffusion chamber. Fluid may be flowed in a second direction different than the first direction, and fluid may be passed through a second plurality of apertures formed in a second portion of the baffle and into a second portion of the cavity disposed on a second side of the baffle opposite the first side. The second portion of the baffle may be angled relative to the floor, and the second portion may be offset from the floor by a greater extent than the first angled portion of the baffle. Passing fluid through the second plurality of apertures may include directing the fluid towards an outlet of the reservoir disposed on the second side of the baffle opposite the first side of the baffle. The second plurality of apertures may include a plurality of slots. 
     Other features and aspects will become apparent by consideration of the detailed description and accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The detailed description of the drawings refers to the accompanying figures in which: 
         FIG. 1  is a perspective view of an example hydraulic reservoir, according to some implementations of the present disclosure. 
         FIG. 2  is a plan view of a portion of the hydraulic reservoir of  FIG. 1 . 
         FIG. 3  is a cross-sectional view of the example hydraulic reservoir of  FIG. 1  showing a volume fraction plot representing an amount of gas entrained in the liquid within the hydraulic reservoir as the liquid flows within the hydraulic reservoir. 
         FIG. 4  is a side view of the example hydraulic reservoir of  FIG. 1  showing a general flow path of liquid within the hydraulic reservoir. 
         FIG. 5  is a perspective view of another example reservoir that includes a diffusion chamber having a lengthened wall, according to some implementations of the present disclosure. 
         FIG. 6  is a detailed cross-sectional view of the reservoir of  FIG. 5 . 
         FIG. 7  is a detail view of another example reservoir showing seals located or otherwise formed between an inlet conduit and a diffusion chamber, according to some implementations of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     For the purposes of promoting an understanding of the principles of the present disclosure, reference will now be made to the implementations illustrated in the drawings, and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the disclosure is intended. Any alterations and further modifications to the described devices, systems, or methods and any further application of the principles of the present disclosure are fully contemplated as would normally occur to one skilled in the art to which the disclosure relates. In particular, it is fully contemplated that the features, components, and/or steps described with respect to one implementation may be combined with the features, components, and/or steps described with respect to other implementations of the present disclosure. 
     The present disclosure is directed to methods and apparatuses that operate to remove gases or mixtures of gases, such as air, from a flowing liquid, such as hydraulic liquid. The present disclosure provides decreased gas entrainment in a liquid prior to recirculation of the liquid. Although implementations in the context of reducing gas entrainment in hydraulic fluids are provided, the scope present disclosure encompasses other types of liquids. For example, the scope of the present disclosure encompasses reducing gas entrainment in coolants, lubricants, water, and other types of liquids and working fluids. By removing gases from liquid such as these, compression of the fluid is reduced and, consequently, performance of the working fluid is improved. Consequently, the volumetric efficiency of hydraulic equipment is improved. 
     In addition to providing improved performance of the working fluid by reducing an amount of entrained gases, the methods and apparatuses within the scope of this technology also reduce the risk of cavitation to pumps and other components of a hydraulic system, thereby increasing the service life of those components. 
       FIG. 1  is a perspective view of an example hydraulic reservoir  100  within the scope of the present disclosure. The hydraulic reservoir  100  includes a housing  102  that defines a cavity  104 . The housing  100  includes a floor  106  and a cover  108 . An inclined baffle  110  is provided in the cavity  104  and is oriented at an acute angle  112  relative to the floor  106 . Although a single inclined baffle  110  is illustrated in the example of  FIG. 1 , in other implementations, more than one inclined baffle is provided. The angle  112  is illustrated using a line  114  (which represents a plane) that is parallel with floor  106 . In some implementations, the angle  112  is within a range of 30° to 45° relative to the floor  106 . The inclined baffle  110  engages walls  116 ,  118 ,  120 , and  122  of the housing  102  and divides the cavity  104  in to a first portion  124  and a second portion  126 . Further, the inclined baffle  110  is inclined in a direction extending from the side  122  to side  118 , which defines a length and longitudinal direction of the inclined baffle  110 . A dimension of the inclined baffle  110  between sides  116  and  120  defines a width of the inclined baffle  110 . Although the illustrated housing  102  includes six sides, i.e., the four sides  116 ,  118 ,  120 , and  122  and a cover  108  and a floor  106 , in other implementations, the housing  102  may include addition or fewer sides. Thus, the shape and configuration of the housing  102  and, thus, the reservoir  100 , is not limited to the example shown in  FIG. 1 . 
     In the illustrated example, the inclined baffle  110  extends along the angle  112  from the side  118  to the side  122 . Although the example inclined baffle  110  includes a horizontal portion  111 , in other implementations, the horizontal portion  111  is omitted. In the illustrated example, the side  122  includes a bend  128  and an inclined portion  129 . The inclined portion  129  operates to direct a flow of liquid exiting from inlet conduit  130 , as described in more detail below. In other implementations, the side  122  may include no bends or additional bends. In some implementations, an entirety of the side  122  may be inclined. In other implementations, the side  122  may be free of an inclined portion. In some implementations, one or more sides of the housing  100  may include one or more bends. Moreover, in other implementations, the number, arrangement, and shape of the sides (including whether any of the sides includes one or more bends) of the housing  102  may vary. The inclined baffle  110  is arranged to engage each of the sides such that the cavity is divided into the first and second portions  124  and  126 . 
     The reservoir  100  also includes an inlet conduit  130  and a vent  133 . In the illustrated example, the inlet conduit  130  extends from the cover  108  and into the first portion  124  of the cavity  104 . In other implementations, the inlet conduit  130  may extend from one of the sides  116 ,  118 ,  120 , or  122 , or the inlet conduit  130  may intercept two or more sides of the housing  102  and extend into the first portion  124  of the cavity  104 . In the illustrated example, the inlet conduit  130  has a circular cylindrical shape. In other implementations, the inlet conduit  130  may be cylindrical having a cross-sectional shape that is other than circular. For example, the cross-sectional shape may be polygonal or have a constant cross-sectional shape that includes one or more curved surfaces, such as an oval shape. In some implementations, the inlet conduit  130  may have a tapered shape or a size that otherwise changes a long a length of the inlet conduit  130 . The inlet conduit  130  defines a longitudinal axis  131 . In some implementations, the longitudinal axis  131  defines a centerline of the inlet conduit  130 . The vent  133  permits gases removed from the liquid to escape from the cavity  104 . 
     A diffusion chamber  132  is disposed at an end  134  of the inlet conduit  130 . In some implementations, the diffusion chamber  132  may be integral to the inlet conduit  130 . In the illustrated example, the diffusion chamber  132  has an enlarged cross-sectional size compared to the cross-sectional size of the inlet conduit  130 . The diffusion chamber  132  extends from an end  136  of the inlet conduit  130  to the inclined baffle  110 . The inclined baffle  110  encloses an end  136  of the diffusion chamber  132 . Thus, the inclined baffle  110  defines a portion of the enclosure of the diffusion chamber  132 . 
     The diffusion chamber  132  includes a wall  138 . In some implementations, the wall  138  is bonded to the inclined baffle  110 . For example, the wall  138  may be welded to the inclined baffle  110 . A portion  140  of the wall  138  includes a first plurality of apertures  142  through which a returning liquid is expelled into the cavity  104 . The first plurality of apertures  142  are formed in the portion  140  of the wall  138  in order to control a direction that liquid is expelled from the diffusion chamber  132  and into the cavity  104 . Particularly, the first plurality of apertures  142  provides for a defined angle of spread of the liquid passing out of the diffusion chamber  132 . Arranging the first plurality of apertures  142  in this manner prevents the liquid from flowing into the first portion  124  of the cavity  104  towards a second plurality of apertures  148  formed in the inclined baffle  110  (discussed in more detail below). The portion of the wall  138  that is remains unperforated acts as a barrier to prevent flow of the returning liquid directly towards the second plurality of apertures  148 . 
     In some implementations, the apertures  142  have a circular shape. In other implementations, the apertures  142  have a shape other than circular. In still other implementations, the apertures  142  have varying shapes. In other instances, the apertures  142  have varying shapes and sizes. In some implementations, the apertures  142  have a common shape but have varying sizes. In some instances, the first plurality of apertures  142  are arranged in a repeating or uniform pattern. In other implementations, the first plurality of apertures  142  are arranged in an irregular or nonuniform pattern. In some implementations, a dimension (e.g., diameter) representing a cross-sectional size of the apertures  142  may be within a range of between 6 mm (0.23 inches (in.)) to 9 mm (0.35 in.). 
       FIG. 2  is a plan view of a portion of reservoir  100  showing the inclined baffle  110  and the diffusion chamber  132 . As shown in  FIG. 2 , the portion  140  of the wall  138  of the diffusion chamber  132  is defined by an angle, referred to as a spread angle  200 , having a vertex  202  located on a longitudinal axis  204  of the diffusion chamber  132 . The spread angle  200  defines an amount of annularly spread experienced by the liquid as the liquid exits the diffusion chamber  132  in a general direction towards side  122 . The portion  140  may extend along an entirety of the length of the diffusion chamber  132  (as measured along the longitudinal axis  204 , for example) or along a portion of the length of the diffusion chamber  132  that is less than an entire length of the diffusion chamber  132 . 
     In some implementations, the spread angle  200  is centered on a line  206  that is perpendicular to side  122 , as shown in  FIG. 2 , such that the line  206  divides or bisected the spread angle  200 . In the illustrated example, the line  206  is perpendicular to an end  206  of the inclined baffle  110  that is closest to the floor  106  of the housing  102 . In some implementations, the spread angle  200  is centered on a plane that extends perpendicularly to the inclined baffle  110 . In the illustrated example, the line  206  represents a plane  208  that extends perpendicularly from the inclined baffle  110 . As explained above, the spread angle  200  is centered on this plane  208  in some implementations. In some examples, the spread angle  200  falls within a range of 90° to 105°. In still other instances, the angle is within a range of 30° to 180°. 
     In other implementations, the spread angle  200  may be angularly offset about the longitudinal axis  204  from line  206  and the corresponding plane  208  such that the line  206  and plane  208  do not bisect or the angle  200 . 
     Referring again to  FIG. 1 , a length of the diffusion chamber  132  extending from the end  134  of the inlet conduit  130  to a location on the inclined baffle  110  contacted by the wall  138  closest to the floor  106  and defines a height  144  of the diffusion chamber  132 . In some implementations, the height  144  is within a range of three to four times the outlet size (e.g., diameter) of the inlet conduit  130 , located at the end  134 . In some implementations, a cross-sectional size  210  (e.g., a diameter) of the diffusion chamber  132  (shown in  FIG. 2 ) is within the range of one and a half times to two times the outlet size (e.g., diameter) of the inlet conduit  130 . 
     As shown in  FIG. 1 , the reservoir  100  also includes outlets  146  in fluid communication with the second portion  126  of the cavity  104 . In the illustrated example, the reservoir  100  includes three outlets  146 . In other implementations, the reservoir  100  may include additional or fewer outlets  146 . The outlet  146  is located on a side of the baffle opposite the first plurality of apertures  142 . 
     As explained earlier, the inclined baffle  110  includes the second plurality of apertures  148 . The second plurality of apertures  148  provides fluid communication between the first portion  124  and the second portion  126  of the cavity  104 . Fluid from the first portion  124  of the cavity  104  is forced to pass through the second plurality of apertures  148  prior to entering the second portion  126  of the cavity  104 . 
     In the illustrated example, the second plurality of apertures  148  are a plurality of slots  150 . The plurality of slots  150  extend longitudinally along the inclined baffle  110  in a direction parallel to the length of the inclined baffle  110 , which may correspond to a direction to of flow of the liquid within the cavity  104 . In the illustrated example, the slots  150  are arranged in staggered relationship. Particularly, in the illustrated example, the plurality of slots  150  contain slots of different sizes with rows of slots having one size (e.g., a first length) being interdisposed between slots having a different size (e.g., a second length larger than the first length). In some implementations, some slots  150  may have a different length or width or both than other slots  150 . As shown in  FIG. 1 , a row of slots  150  containing a first slot type  152  is located between rows of a second slot type  154 . The first slot type  152  has a first length, and the second slot type  154  has a second length greater than the first length. It is believed that the slots  150  encourage separation of gas from the liquid as the liquid passes along and through the slots  150  and into the second portion  126  of the cavity  104 . For example, bubbles of gas may be prevented from passing through the slots  150 , promoting separation of the gas from the liquid. The bubbles of gas prevented from passing through the slots  150  rise towards the cover  108 , where the gas escapes the liquid, for example joining a layer of gas provided above the liquid, as shown in  FIGS. 3 and 4 . 
     Although the second plurality of apertures  148  are illustrated as the plurality of slots  150  in the example of  FIG. 1 , in other implementations, the plurality of apertures  148  may have other shapes or be a mixture of other shapes. The plurality of apertures  148  may be, for example, a plurality of circular openings, a combination of circular openings and elongated openings (e.g., slots), or a plurality of openings having a common shape, a common size, or a combination of different sized openings that have a common shape. 
     In some implementations, a width of the slots  150  may be related to a size of the apertures  142  formed in the wall  138  of the diffusion chamber  132 . For example, in some instances, a width of the slots  150  is within a range of 0.85 to 1.15 times a size of the diameter of the apertures  142 . In some implementations, the second plurality of apertures  148  are formed along approximately 10% to 30% of the length of the inclined baffle  110 . 
     As the liquid is directed into the reservoir  100  via the inlet conduit  130 , the liquid impinges upon the inclined baffle  110  and is forced out of the diffusion chamber  132  and into the first portion  124  of the cavity  104  via the first plurality of apertures  142 . It is noted that, generally, the liquid being introduced into the reservoir is liquid being returned to the reservoir after having been pumped to another location to perform work, to cool, or to perform some other type of activity. Impinging upon the inclined baffle  110  and flowing through the apertures  142  generates turbulence and produces a swirling behavior in the liquid, which encourages release of the entrained gas from the liquid. 
       FIG. 3  shows a cross-sectional view of the reservoir  100  shown in  FIG. 1  and represents an aeration plot showing an amount of gas entrained in liquid contained in the reservoir  100 . Particularly,  FIG. 3  shows a fractional amount (i.e., volume fraction) of gas entrained in the liquid within the reservoir  100 . Liquid  300  and gas  302  are contained in the cavity  104  of the reservoir  100 . As show at  304 , the liquid exiting the inlet conduit  130  has an increased amount of entrained gas compared to the other liquid present in the reservoir  100 . As a result, the liquid at  304  has a decreased volume fraction of liquid (shown as volume fraction of oil in the illustrated example) present in the cavity  104 , as indicated by the key  306 . A reduction in the volume fraction of liquid indicates entrainment of gases, and an increase in the amount of gases entrainment corresponds to a reduced volume fraction of liquid. Thus,  FIG. 3  shows how gases travel within the cavity  104  of the reservoir  100  as the liquid is introduced thereinto. As the liquid exits the diffusion chamber  132  via the first plurality of apertures  142 , the liquid is directed towards the wall  122  on a first side of the inclined baffle  110  (i.e., into the first portion  124  of the cavity  104 ) and away from the outlets  146  located proximate to the side  118 , opposite the side  122 , and on an opposite side of the inclined baffle  110  (i.e., in the second portion  126  of the cavity  104 ). 
     By promoting turbulent flow in the liquid exiting the diffusion chamber  132 , entrained gas is encouraged to separate from the liquid. Further, by directing the liquid away from the outlet  146 , e.g., towards wall  122 , a path traveled by the liquid prior to being drawn into the outlet  146  upon recirculation is increased. Entrained gas is illustrated by liquid having a reduced volume fraction of liquid, such as the liquid shown in  304 . As shown, the gas has a trajectory towards the wall  122  and the cover  108 , eventually joining the gas  302  contained near the cover  108  of the reservoir  100 . In this manner, the gas is removed from the liquid. 
     Flow of the liquid within the cavity  104  is illustrated in  FIG. 4 . As shown, the introduced liquid travels in a generally circuitous route in the counterclockwise direction (as referenced in the context of  FIG. 4 ). As the returning liquid strikes the inclined baffle  110  and exists through the first plurality of apertures  142 , the liquid flow is agitated to promote release of the entrained gases and, thus, operates to de-aerate the liquid. After exiting the diffusion chamber  140 , the liquid is directed away from the outlets  146  and towards wall  122 , as indicated by arrow  400 . The liquid contacts the inclined portion  129  of the side  122  and is, as a result, is directed upwards towards the cover  108  and the surface  402  of the liquid, as indicated by arrow  404 . Additionally, suction generated as the liquid is drawn out of the outlets  146  also promotes swirling of the liquid. The liquid moves in a general counterclockwise direction, as indicated by arrow  406 , and is directed towards the second plurality of apertures  148  formed in the inclined baffle  110 , as indicated by arrow  408 . As liquid is drawn out of the reservoir  100  via the outlets  146 , the liquid is drawn towards the floor  106  (as indicated by arrow  410 ), through the second plurality of apertures  148 , and into the second portion  126  of the cavity  104 , as indicated by arrows  410 . 
     As a result of the described flow path, the liquid being introduced into the reservoir is provided with an increased transient time within the cavity compared to current approaches, which promote flow of the returning fluid directly to the reservoir outlet. This increased transient time encourages improved separation and removal of entrained gases from the liquid, promoting de-aeration of the liquid. Consequently, improved performance of the liquid and a reduced risk of damage to pumps and other hydraulic devices due to cavitation are provided. 
     The reduction in entrained gas is shown in  FIG. 3 . On the opposing side of the inclined baffle  110  in the second portion  126  of the cavity  104 , a reduced amount of entrained gas is shown at  308 . Gases are prevented from passing into the second portion  126  of the cavity  104  by the second plurality of apertures  148  formed in the inclined baffle  110 , as shown at  310 . Also illustrated is the circuitous route traveled by the liquid between the inlet conduit  130  and the outlets  146 . 
       FIG. 5  shows another example reservoir  500 . The reservoir  500  is similar to the reservoir  100  except that a wall  502  of a diffusion chamber  504 , similar to the wall  138  of the diffusion chamber  132  of the reservoir  100 , includes a portion  506  that extends towards a cover  508 , similar to cover  108  of the reservoir  100 . The portion  506  of wall  502  extends beyond a surface  509  of the hydraulic fluid  510  contained within the reservoir  500 . The portion  506  of wall  502  surrounds at least a portion of an inlet conduit  508 , which is similar to the inlet conduit  130  of the reservoir  100  and defines a passage  511  between the portion  506  of the wall  502  and the inlet conduit  508 , as shown in  FIG. 6 . Although the portion  506  of the wall  502  is shown as surrounding a portion of the inlet conduit  508 , in other implementations, the portion  506  of the wall  502  surround an entirety of the inlet conduit  508 . 
     Referring to  FIG. 6 , in some implementations, the diffusion chamber  504  does not form a seal with the inlet conduit  508 . As a result, a gap  512  is formed between an end portion  514  of the inlet conduit  508  and an end wall  516  of the diffusion chamber  504 . Some of the gas entrained in the hydraulic fluid  510  received into the diffusion chamber  504  via the inlet conduit  508  can escape the through the gap  512  and be drawn through slots  516 , which may be similar to slots  150 , and directly into an outlet  518  (which may be similar to outlets  146 ). Thus, the gap  512  provides a route by which entrained gas is permitted to short-circuit the pathway described above, thereby reducing an amount of time in which the entrained gases can escape prior to the fluid being drawn out of the reservoir and increasing the likelihood that gases remain entrained in the hydraulic fluid. In some instances, entrained gas congregates within a portion  520  of an interior cavity  522  of the diffusion chamber  504 .  FIG. 3  illustrates this behavior at  312 . 
     In order to avoid this short-circuit pathway, the passage  511  directs gases within the interior cavity  522  of the diffusion chamber  504  and, particularly, the portion  520  of the interior cavity  522  escaping through the gap  512  and into the cavity  514  located above the surface  509  of the hydraulic fluid  510 . The gas is released into the cavity and prevented from being retained in the hydraulic fluid  510  as a result of the extension of the portion  506  of the wall  502  extending beyond the surface  509  of the hydraulic fluid  510 . 
     A seal may be used to eliminate or reduce the risk of gas escaping from a diffusion chamber, as described above.  FIG. 7  is a detail view of a portion of another reservoir  700  within the scope of the present disclosure. The reservoir  700  may be similar to the reservoir  100  and includes a diffusion chamber  702 , similar to the diffusion chamber  132 , and an inlet conduit  704 , similar to inlet conduit  130 . In order to eliminate or reduce gas escape between a gap, similar to gap  612  described earlier, formed between the diffusion chamber  702  and the inlet conduit  704 , a seal is provided therebetween. For example, in some instances, a seal  706  is positioned between an opening  708  formed in the diffusion chamber  702  and an exterior surface  710  of the inlet conduit  704 . In other instances, a seal  712  is positioned between an exterior surface  714  of the inlet conduit  704  and an exterior surface  716  of the diffusion chamber  702 . Although both seals  706  and  712  are shown in  FIG. 7 , in other implementations, one of the seals  706  or  712  is included while the other of the seals  706  and  712  is omitted. In some implementations, one or both of the seals  706  and  712  may be an O-ring, or another sealing material. Other types of seals may be used, and the location of a seal between the diffusion chamber  702  and the inlet conduit  704  may different than those illustrated while still maintaining a barrier to the passage of gas from the diffusion chamber via a gap formed between the diffusion chamber and the inlet conduit. 
     Without in any way limiting the scope, interpretation, or application of the claims appearing below, a technical effect of one or more of the example implementations disclosed herein is improving de-aeration of a flow of liquid within a hydraulic reservoir. Another technical effect of one or more of the example implementations disclosed herein is improving performance of a working fluid and reducing risk of damage to hydraulic components by decreasing an amount of gas in the liquid. 
     While the above describes example implementations of the present disclosure, these descriptions should not be viewed in a limiting sense. Rather, other variations and modifications may be made without departing from the scope and spirit of the present disclosure as defined in the appended claims.