Abstract:
A split casing fluid device includes a reaction chamber including a first and second casings having a portions of a stator, a rotor rotatably mounted inside the stator and having a plurality of fluid-interacting features, the rotor exterior surface and the stator define a fluid passageway therebetween, an inlet into the reaction chamber in fluid communication with the fluid passageway, and an outlet from the reaction chamber in fluid communication with the fluid passageway. Removal of a casing creates an opening in the reaction chamber sized to allow passing the rotor through the opening. In some embodiments, the casings span the entire length of the rotor and removal of at least one casing creates an opening in the reaction chamber sized to allow removal of the rotor in a perpendicular direction to the longitudinal axis. The fluid device may be a cavitation generator with a rotor having cavitation-inducing features.

Description:
FIELD 
       [0001]    The present disclosure concerns fluid pumps and cavitation generators. 
       BACKGROUND 
       [0002]    Typical rotational fluid devices, such as pumping, mixing, and cavitation devices, operate on fluids by mechanically rotating a rotor or impeller in a reaction chamber with a stator, while a flow of fluid passes from an inlet, across the rotor or impeller, and to an outlet. Typical fluid devices comprise a one-piece reaction chamber housing with an end-cap sealing the housing or a two-piece housing split laterally to enable longitudinal separation of from piece from the other. These conventional designs enable the fluid device to be constructed or serviced by removing an end of the reaction chamber housing to access the rotor or stator in a longitudinal direction. 
       SUMMARY 
       [0003]    The concepts herein encompass using a fluid device having a reaction chamber constructed from casings split longitudinally. The present invention can also relate to pumping devices, cavitation generators, and mixers. The present invention further relates to fluid devices having a reaction chamber housing formed of multiple casings removeably coupled at longitudinal mating regions deposed along the length of the reaction chamber housing with respect to the axis of rotation. Embodiments disclosed herein provide an ability to quickly and easily service or alter the casing and impellers/rotors without the need to completely disassemble the unit. Typical multi-stage fluid device designs require the removal of the entire shaft and internals whereas the present design enables maintenance and replacement of rotor and casing parts to be conducted without disconnecting or modifying the input shaft. One skilled in the art will appreciate a substantial reduction in maintenance complexity using the present design. 
         [0004]    In an example, a split casing fluid device includes a reaction chamber housing including a first casing having a first portion of a stator and a second casing having a second portion of the stator. The first and second casings define the reaction chamber housing. A rotor is rotatably mounted inside the stator and the rotor defines a length along a longitudinal axis of rotation. The rotor comprises an exterior surface having a plurality of fluid-interacting features, and the rotor exterior surface and the stator define a fluid passageway there between. The split casing fluid device includes a fluid inlet into the reaction chamber housing, the fluid inlet being in fluid communication with the fluid passageway, and a fluid outlet from the reaction chamber housing, the fluid outlet being in fluid communication with the fluid passageway. Removal of one or more of the casings creates an opening in the reaction chamber housing sized and shaped to allow passing the rotor through the opening. 
         [0005]    In some examples, the rotor defines a minimum diameter, and each casing of the reaction chamber housing spans at least the length of the rotor, and at least one of the first and second casing comprises an inner surface defining a width respect to a plane normal to the longitudinal axis of the rotor greater than the minimum diameter of the rotor. 
         [0006]    In some examples, the first and second casings defining opposing halves of the reaction chamber housing. 
         [0007]    In some examples, the rotor comprises first and second rotor segments removeably coupled together, the first and second rotor segments each spanning the length of the rotor. 
         [0008]    In some examples, the first and second rotor segments define opposing halves of the rotor. 
         [0009]    In some examples, the rotor includes first and second ends each defining a cone shaped surface varying the width of the fluid passageway along the flow cone. 
         [0010]    In some examples, the first portion of the stator is formed on an interior surface of the first casing and the second portion of the stator is formed on an interior surface of the second casing. 
         [0011]    In some examples, the first portion of the stator is a first stator sleeve and wherein the second portion of the stator is a second stator sleeve, the first and second stator sleeves removeably nest within an inner surface of the respective first and second casings. 
         [0012]    In some examples, the rotor defines an interior rotor volume in fluid communication with the fluid inlet, and wherein the fluid-interacting features are thru-holes between the interior rotor volume and the fluid passageway 
         [0013]    In some examples, split casing fluid device further includes an input shaft having first and second ends, and the rotor is coupled to the input shaft and the input shaft adapted to enable rotation of the rotor in the reaction chamber housing and transfer torque to the rotor. The split casing fluid device further includes an inlet assembly including a first bearing coupled with the first end of the input shaft and an outlet assembly comprising a second bearing coupled with the second end of the input shaft. 
         [0014]    In some examples, the first and second casings each comprise opposing first and second ends, and wherein the first ends of the first and second casings are removeably coupled to the inlet assembly, and wherein the second ends of the first and second casing are removeably coupled to the outlet assembly. 
         [0015]    In some examples, the inlet assembly defines a first inner passageway in fluid communication with the fluid passageway and the outlet assembly defines a second inner passageway in fluid communication with the fluid passageway, the input shaft passing through the first and inner passageways. In some examples, the rotor comprises first and second rotor segments removeably coupled together, the first and second rotor segments each spanning the length of the rotor and wherein the input shaft includes an axial lock key adapted to maintain an axial location of the rotor segments on the input shaft. In some examples, the inlet assembly comprises a first external bearing assembly having the first bearing, and wherein the outlet assembly comprises a second external bearing assembly having the second bearing, and wherein the first and second external bearing assemblies position the first and second bearing outside of the first and second inner passageways. 
         [0016]    In some examples, the split casing fluid device is a split casing cavitation generator, and wherein the plurality of fluid-interacting features comprises a plurality of cavitation-inducing features, and wherein the fluid outlet is a heated fluid outlet. In some examples, the stator comprises an inner surface defining a first plurality of apertures and wherein the plurality of cavitation-inducing features comprises a second plurality of apertures. 
         [0017]    In some examples, the split casing fluid device is a split casing multi-stage pump, and the plurality of fluid-interacting features comprises a plurality of pumping features. 
         [0018]    Another example is a method of servicing a split casing fluid device. The method includes, given a reaction chamber housing comprising a first casing and a second casing and a rotor rotatably mounted inside the reaction chamber housing, releasing the first casing from the second casings, and removing one of the first and second casings from the reaction chamber housing. The removing one of the first and second casings creating an opening in the reaction chamber housing sized and shaped to enable the rotor to pass though the opening. In some examples, the method further comprises passing the rotor though the opening. 
         [0019]    A split casing fluid device is described herein. The fluid device includes a reaction chamber housing constructed of multiple casings being split longitudinally about the rotational axis of a rotor. The casings may span the length of the rotor to enable the rotor to be installed or removed in a direction perpendicular to the axis of rotation, or, in the alternative, the casings may span a sufficient portion of the length of the rotor to enable to the rotor to be removed or installed by passing through the opening created by removing on or more of the casings. In some examples, each casing may be a casing assembly constructed from multiple segments that can be individually separated as part of the process of removing the casing assembly from the reaction chamber housing. In some aspects, the reaction chamber is constructed from two casings each forming an opposing half of the reaction chamber housing. In some aspects, the reaction chamber housing is constructed from a plurality of casings joined longitudinally with respect to the axis of rotation of the rotor, with the segments having a variety of sizes, lengths, and widths. 
         [0020]    Generally, one skilled in the art will appreciate that longitudinally joined casings enables the reaction chamber housing to be constructed around an existing rotor and shaft without modification or disconnection of the input shaft and input/output volutes. Additionally, one skilled in the art will appreciate that the split casing and rotor design described herein enables removal and replacement of the rotor without modification or disconnection of the input shaft and input/output volutes. The ability to avoid modifying the input shaft enables associated shaft features, for example, bearings and packings, to be constructed and installed without concern for routine maintenance work requiring their removal. In some instances, examples reduce complexity and improve reliability over prior art design by employing external bearing assemblies, which may be integrated with the volutes. 
         [0021]    Some, none or all of the aforementioned examples, and examples throughout the following descriptions, can be combined. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0022]      FIG. 1  is a perspective view illustration of a split casing cavitation generator. 
           [0023]      FIG. 2  is a perspective view illustration of the split casing cavitation generator of  FIG. 1  with the top casing removed to show a rotor. 
           [0024]      FIG. 3  is a side view illustration of a split casing cavitation generator with the reaction chamber housing removed to show a split rotor. 
           [0025]      FIGS. 4A and 4B  are perspective view illustrations of a cavitation generator with the reaction chamber housing and top-rotor segment removed. 
           [0026]      FIG. 5  is a perspective view illustration of a split casing cavitation generator showing the interior details of the bottom casing and stator. 
           [0027]      FIGS. 6A and 6B  are side section view illustrations of a split casing cavitation generator showing the flow passageways. 
           [0028]      FIG. 7  is perspective view illustration of a split casing cavitation generator showing the removal of a top casing. 
           [0029]      FIG. 8  is perspective exploded view illustration of a split casing cavitation generator. 
       
    
    
     DETAILED DESCRIPTION 
       [0030]      FIG. 1  is a perspective view illustration of a split casing cavitation generator.  FIG. 1  shows a split casing cavitation generator  100  including an inlet volute  110 , a reaction chamber housing  20 , and an input shaft  150 . The inlet volute  110  includes a fluid inlet  111  and an inlet flange  112 . The outlet volute  130  includes a heated fluid outlet  131  and an outlet flange  133 . The reaction chamber housing  20  is an assembly of two casings  120   a ,  120   b  forming opposing halves of the reaction chamber housing  20 . Each casing  120   a,b  includes a first flange  122   a,b  and a second flange  123   a,b . The flanges  112 ,  133 ,  122   a,b ,  123   a,b  include bolt holes  115  for joining the first flanges  122   a,b  to the inlet flange  112  and for joining the second flanges  123   a,b  to the outlet flange  123 . Together, the top casing  120   a  and bottom casing  120   b  form a cylindrical reaction chamber housing  20  by being mated together along longitudinally disposed mating regions  124   a,b  spanning the length of the each casing  120   a,b . The mating regions  124   a,b  include holes  125  for securing the casings  120   a,b  together. 
         [0031]    In operation, the split casing cavitation generator  100  accepts a fluid flow through the inlet  111 , into the interior of the reaction chamber housing  20 , and to the outlet  131 . A rotor (not shown) is disposed in the reaction chamber housing  20  and is driven by the input shaft  150 . The rotor is configured to spin in the reaction chamber housing as the fluid flow passes between the rotor and a stator (not shown) on the inner surface of the reaction chamber housing  20 . An interaction between the rotor, stator, and fluid flow generates cavitation in the fluid flow. As shown in more detail in  FIGS. 6A and 6B , the fluid flow in the reaction chamber housing interacts with the rotor (not shown) to generate cavitation in the fluid flow, and thereby increase the temperature and pressure of the fluid flow before being leaving the reaction chamber  20 . The casings  120   a,b  being removeably connected to the inlet volute  110  and outlet volute  130  enable the access to the rotor without modification to inlet volute  110 , outlet volute  130 , or the input shaft  150 . 
         [0032]      FIG. 2  is a perspective view illustration of the split casing cavitation generator of  FIG. 1  with the top casing removed to show a rotor.  FIG. 2  shows the split casing cavitation reaction  100  with the top casing ( 120   a  of  FIG. 1 ) removed.  FIG. 2  shows a cylindrical rotor  240  disposed on the input shaft  150  in the reaction chamber housing ( 20  of  FIG. 1 ) and partially surrounded by the bottom casing  120   b . The rotor  240  includes a plurality of cavitation-inducing features  245  on the exterior surface. In some instances, the cavitation-inducing features  245  are apertures, as shown in  FIG. 2 , dimples, or other shapes found in conventional cavitation generators. The rotor  240  also includes flow cones  241 ,  242  on opposite ends to direct a fluid flow from the inlet volute  110  to a fluid passageway defined between the exterior surface of the rotor  240  and the interior surface of the casings  120   a,b  of the reaction chamber housing  20 . The rotor also includes a fastener  249  securing the rotor  240  to the input shaft  150 . 
         [0033]    In operation, removal of the top casing  120   a  enables access to the rotor  240  to allow for servicing and cleaning of, for example, the rotor  240  and the casings  120   a,b . As shown, to remove the top casing  120   a  from the split casing cavitation generator  100 , the first and second flanges  122   a ,  123   a  of the top casing are disconnected, respectively, from the inlet flange  112  and the outlet flange  133 . Additionally, the top casing  120   a  is decoupled from the bottom casing  120   b  by removing fasteners (not shown) present in the holes  125  of the longitudinal mating regions  124   a,b .  FIG. 2  removal of the top casing  120   a  enabling access to the entire length of the rotor  240 . This configuration of  FIG. 2  enables both installation and removal of the rotor  240  without modification to inlet volute  110 , outlet volute  130 , or the input shaft  150 . 
         [0034]      FIG. 3  is a side view illustration of a split casing cavitation generator with the reaction chamber housing removed to show a split rotor.  FIG. 3  shows the split casing cavitation reactor  100  with both the top casing  120   a  and bottom casing  120   b  removed.  FIG. 3  shows the rotor  240  having a two-part construction with a top rotor segment  340   a  and a bottom rotor segment  340   b  joined together around the input shaft  150  to form the rotor  240 . The top rotor segment  340   a  is joined to the bottom rotor segment  340   b  by bolts (not shown) positioned in holes  345  of the top rotor segment  340   a . Each rotor segment  340   a,b , includes corresponding sections of the inlet and outlet flow cones  341   a,b ,  342   a,b.    
         [0035]    In operation, the split casing rotor  240  enables the rotor segments  340   a,b , to be installed on an existing input shaft  150  and with the top casing  120   b  or bottom casing  120   b  removed. 
         [0036]      FIGS. 4A and 4B  are perspective view illustrations of a cavitation generator with the reaction chamber housing and top-rotor segment removed.  FIG. 4A  shows the split casing cavitation reactor  100  having the top rotor segment  340   a  removed. The bolts  446  that are positioned in holes  345  in  FIG. 3  are shown in  FIG. 4A  in their installed condition.  FIG. 4A  shows the input shaft  150  includes an axial lock key  451  configured to secure the axial position of the rotor  240  on the input shaft  150 .  FIG. 4B  shows the details of flat the surface  449  of the bottom rotor segment  340   b . The flat surface  449  is configured fit against a corresponding flat surface of the top rotor segment  340   b . The flat surface  449  includes groves  448  and holes  447  configure to align the bottom rotor segment  340   b  with the top rotor segment  340   a  and prevent improper installation. Additionally, corresponding protrusions are provided on the opposing flat surface of the top rotor segment  340   a  (not shown) and, in some instances, are configured to interface with the grooves  448  and holes  447  on the flat surface  449  in a key-to-slot configuration. 
         [0037]      FIG. 5  is a perspective view illustration of a split casing cavitation generator showing the interior details of the bottom casing and stator.  FIG. 5  shows the bottom casing  120   b  mated to the outlet volute  130 . The outlet flange  133  of the outlet volute  130  includes a gasket seal  516  positioned to seal the connection between the outlet flange  133  and the second flanges  123   a,b  of the top and bottom casings  120   a,b . The bottom casing  120   b  includes a stator  560  positioned on the inner surface of the bottom casing  120   b . Though not shown, the top casing  120   a  includes a corresponding stator  560 . The stator  560  includes a plurality of apertures  565  formed in the inner surface of the stator  560 . 
         [0038]    In some instances, the stator  560  is formed directly into the surface of the casings  120   a,b , or in other instances, is, a removable sleeve nested on the inner surfaces of the casings  120   a,b . A removable sleeve stator enables changing the stator  560  without replacing the casing  120   a,b , which may be necessary due to wear on the surface or in order to change the radial clearance between the stator  560  and the exterior surface of the rotor  240 . In some instances, changing the thickness of the stator  560  allows for different sizes of solids present in the fluid without damaging the surfaces of the stator  560  and rotor  240 . Changing the thickness of the stator  560  can also be used to reduce shearing effects or to vary the velocity of the rotor  240  as a function of the fluid&#39;s properties. The stator  560  sleeve allows for simple modification of the cavitation parameters without changing the rotor  240  or reaction chamber housing  20 . 
         [0039]      FIGS. 6A and 6B  are side section view illustrations of a split casing cavitation generator showing the flow passageways.  FIG. 6A  shows the split casing cavitation reactor  100  having a spinning  699  rotor  240  (i.e., first and second rotor segments  341   a,b ). The first and second rotor segments  341   a,b  include fasteners  249  securing the first and second rotor segments  341   a,b  to the input shaft  150  and transferring torque from the input shaft  150  to the first and second rotor segments  341   a,b . Arrow  611  indicates a flow of fluid into the inlet volute  110  and arrow  631  indicates a flow of heated fluid from the outlet volute  630 .  FIG. 6B  shows that the spinning first and second rotor segments  341   a,b  define a fluid passageway  613  between the first and second rotor segments  341   a,b  and the stator  560 . Arrows  612  indicate the fluid flow passing along the surface of the inlet flow cone and into the fluid passageway  613 . 
         [0040]    In operation, the rotor  240  is adapted to spin  699  via the input shaft  150  and a flow of fluid  611 , for example, a fluid feedstock, is provided to the inlet  111  of the inlet volute  110  of the split casing cavitation reactor  100 . The inlet volute  110  defines an interior volute  610  that directs  612  the flow of fluid  611  to the reaction chamber housing  20 . In the reaction chamber housing  20 , the fluid  611  passes around the flow cone  341   a,b  and into the passage  613  between the surface of the rotor  240  and the stator  560 . As the fluid between the spinning apertures  245  on the rotor  240  and the stationary aperture  565  on the stator  560 , localized regions of extremely low pressure form in the fluid  611 , which momentarily causes cavitation bubbles to form in the fluid  611 . The subsequent and violent collapse of the cavitation bubbles generates heat within the fluid  611  from the mechanical energy of the spinning rotor  240 . The intense heat and pressure of the act of cavitation is able to destroy organics that may be present in the fluid  611  along with other compounds. Through the act of hydrodynamic cavitation, and/or secondary acoustic cavitation, the fluid  611  is heated/pressurized to a degree that depends on, for a given geometry of the rotor  240  and stators  560 , the mechanical energy input to the rotor  240 , the fluid properties, for example, viscosity, specific heat, and heat of vaporization. Solids present in the flow small enough to pass through the fluid passageway  613  may pass unchanged. 
         [0041]      FIG. 7  is perspective view illustration of a split casing cavitation generator showing the removal of a top casing.  FIG. 7  shows the top casing  120   a  being removed from a split casing cavitation generator  700 . The top casing  120   a  includes a stator  560 . The split casing cavitation reactor  700  includes a solid rotor  740  coupled to the input shaft  150 . The input shaft is supported by a bearing  751  in the inlet volute  110  and a bearing (not shown) in the outlet volute  130 . Arrow  799  indicates the direction of translation of the top casing  120   a , once the top casing  120   a  has been disconnected from the bottom casing  120   b , and the inlet and outlet flanges  112 ,  133 . In operation, the removal of the top casing  120   a  provides access to the rotor  740  and to the stator of the top casing  120   a . As detailed above, by enabling a user to remove the casings  120   a,b , the user is provided easy access to the rotor  240  and other internals, without the need to remove bearings, volutes, shafts or other associated components. In an example operation, the rotor  240  is completely uncovered by removing the casing  120   a,b , which includes disconnecting the casings  120   a,b  at their longitudinal mating regions  124   a,b  and un-bolting the casings flanges  122   a,b    123   a,b , from the volute flanges  112 ,  133 , without any additional disassembly. 
         [0042]      FIG. 8  is perspective exploded view illustration of a split casing cavitation generator.  FIG. 8  shows the split casing cavitation generator  100  with the top and bottom casings  120   a,b  separated from the inlet and outlet volutes  110 ,  130  and with the top and bottom rotor segments  340   a,b  separated from the input shaft  150 . Bolts  446  are shown removed from the top rotor segment  340   a  and the corresponding threaded holes  847  in the bottom rotor segment  340   b  are visible. In some instances, the bolts  446  are oriented in opposing directions to help in the balancing of the rotation of the rotor  240  by placing the center of inertia of the bolts concentric with the rotor&#39;s  240  axis of rotation. For example, a first bolt placed though the top rotor segment  340   a  and into the bottom rotor segment  340   b  and a second bolt placed in the opposite manner. 
         [0043]    In an exemplary embodiment, the radial clearance between the exterior surface of the rotor  240  and the stator  860   a,b  is less than one half inch. Generally, one skilled in the art will appreciate that different clearances are necessary depending on fluid viscosity and the presence of impurities (e.g., small rocks, dirt, or debris) in the fluid. 
         [0044]    While  FIGS. 1-8  have shown the fluid device as a single-stage cavitation reactor  100 , alternatively, the rotor  240  may be one of a plurality of rotors  240  in single reaction chamber housing. In other instances, the fluid device may comprise multiple reaction chamber housing linked together, with each having one or more rotors. 
         [0045]    While  FIGS. 1-8  have shown the reaction chamber housing  20  as having a cylindrical shape, alternatively, the reaction chamber housing  20 , in some instances, defines a spherical shape, or, generally, defines an internal profile that is symmetric about the axis of the input shaft  150 . Similarly, the rotor  240 , in some instances, has a shape defining a symmetric profile about the input shaft  150  axis. 
         [0046]    While  FIG. 7  shows the bearing assembly  750  integrated with the inlet volute  110 , alternatively, the bearing assembly  751  is, in some instances, an external bearing assembly supporting the input shaft  150  with or without the external bearing assembly being coupled to the input volute  110 . 
         [0047]    While  FIGS. 1-8  show the input shaft  150  as being contiguous through the fluid device  100 , in some instances the input shaft  150  is a split shaft having two segments configured to be joined by a rotor  240  coupled to a first segment at a first end and a second segment at a second end of the input shaft. 
         [0048]    While  FIGS. 1-8  show the fluid device as a cavitation generator  100 , in some instances the fluid device is a fluid pump. In a fluid pump embodiment, the split casing design of the reactor chamber housing is be similar, however instead of apertures formed into the rotor  240  or stator  860   a,b , the rotor and stator include pumping features to increase pressure in the fluid flow with rotation of the rotor. In some instances, the rotor is an impeller. In some instances, the fluid device is a multi-stage pump having multiple sets of impellers or rotors either in a single chamber or in multiple chambers. The chambers being designed such that each impeller increases the pressure of the water by some magnitude. In some instances, the stators direct the flow from one impeller to the next until the fluid flow reaches the outlet  131 . 
         [0049]    While  FIGS. 1-8  show the casings  120   a,b  of the reaction chamber  20  spanning the length of the reaction chamber  20 , in some instances, one or more of the casings span only a partial length of the reaction chamber housing  20 , and removal of one or more of the casings creates an opening in the reaction chamber housing sufficient to remove the rotor  240 , by being sized and shape to accept one of the rotor segments though the opening after disconnecting the rotor segment from the input shaft  150  and the other rotor segment. 
         [0050]    While  FIGS. 1-8  shown the rotor  240  and reaction chamber housing  20  as constructed from rotor segments and casings defining opposing halves of their corresponding parent structures  240 ,  20 , one skilled in the art will appreciate that both the reaction chamber housing  20  and rotor  240  are, in some instances, constructed from a plurality of segments. 
         [0051]    While  FIGS. 1-8  have shown the fluid device as a cavitation generator, in some instances the fluid device is a mixer. In some instances, the fluid device is a system acting on a fluid with a rotational component contained in a housing and configured to pass a flow of the fluid through or across the rotational component. 
         [0052]    A number of implementations have been described. Nevertheless, it will be understood that various modifications may be made. Accordingly, other implementations are within the scope of the following claims.