Abstract:
The present disclosure generally relates to a fluid mixer, a system for mixing fluids utilizing the fluid mixer, and a method of mixing fluids using the fluid mixer or the system for mixing fluids, and more specifically, to a compact static mixing device with no moving parts and capable of mixing any fluid, such as air, nitrogen gas, water, oil, polluted water, and the like. A first pressurized, incoming fluid is accelerated locally by a section reduction, is split into streams, and then is released into a second fluid found in a closed volume or an open volume after a period of stabilization. The directed and controlled first fluid slides along an insert up to directional and angled fins at a vortex creator where suction forces from a self-initiating vortex in an internal cavity draws in at least part of the first fluid to fuel the vortex. The compactness and simplicity of the fluid mixer with internal vortex can be used alone within a closed volume in a conduit, in a sprayer, or within a fixed geometry to direct the mixing vortex to specific dimensions. One or more fluid mixers can also be used in an open volume such as a reservoir, a tank, a pool, or any other fluid body to conduct mixing. The technology alone, as part of a multimixer system, or as a method of mixing using the fluid mixer with internal vortex is contemplated to be used in any field where mixing occurs.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    The present patent application claims priority from and the benefit of U.S. Provisional Patent Application No. 61/244,617, filed Sep. 22, 2009, entitled Fluid Mixer With Internal Vortex, which prior application is hereby incorporated herein by reference. 
     
    
     FIELD OF THE DISCLOSURE 
       [0002]    The present disclosure relates generally to a fluid mixer, a system for mixing fluids utilizing the fluid mixer, and a method of mixing fluids using the fluid mixer or the system for mixing fluids, and more specifically, to a liquid or gas fluid mixer where a first fluid is compressed, accelerated, and split into a layer above the surface of a vortex generator with angled fins and an internal cavity of a self-initiating and -maintaining mixing vortex in a second fluid. 
       BACKGROUND 
       [0003]    Simple things are often the hardest to master. Oil and vinegar are two liquids with divergent properties that do not mix under most conditions. Fish use air dissolved in water to breathe but tiny air bubbles are difficult to mix in large quantities in water. One way to mix fluids is to create dynamic mixing systems that require external energy, such as the use of a pump or a propeller to force fluids to mix. In many instances the use of a dynamic mixing system needing external energy is not the optimal solution for a mixing process. In most cases, use of external energy results in heating the fluids, deterioration of the mixing device, maintaining the external system, etc. Many industrial applications benefit from static mixing, which is mixing that uses only static or kinetic energy from the fluids themselves. 
         [0004]    Many material processes and technologies require mixing. Air and fuel are mixed in the pistons of an automotive engine, fertilizer and water are mixed during the irrigation of land, medication is mixed with serum in hospitals, turbulent air bubbles are mixed with polluted water in water purification systems, hot water is mixed with cold water in cooking devices, fuel and oxidants are mixed in rocket reactors, recycled air and fresh, incoming air is mixed in aeration systems, chemicals are mixed in tanks during chemical processes, nitrogen gas is mixed into fertilizer to improve the output of plant food, water is given new properties via gasification to prevent seeping into soil by oxygenation of water, oil is separated from water via turbulent mixing processes, foam is created via high-intensity gasification of a fluid, emulsion results from unique conditions of mixing, and washing is based on dispersion of a liquid in air, to name only a few. The current technology relates to mixing technology in general and applies more specifically to any process or system where mixing of fluids is found. 
         [0005]    Mixing processes, like other processes within systems, are now being scrutinized and redesigned to enable energy and cost savings. Improved static or dynamic mixing helps reduce the energy consumption of a device or process using the improved mixing. A static device that relies on the pressure level of pressurized incoming fluid, when made more efficient, results in less pressure to operate or creates a mixed fluid with a greater output pressure. The same improved static mixer may create less friction and may limit molecular disruption within the fluid. What is needed is a simple, energy- and cost-efficient, compact static mixer capable of improved mixing of fluids. 
         [0006]    Energy is consumed when a static mixer includes revolving or moving parts. Energy is also consumed when a static mixer shuffles and directs fluids away from their primary flows into baffles or other deviations. What is needed is a static mixer with no moving parts capable of enhanced mixing without requiring major alterations to the flows of liquids. 
         [0007]    Mixing of fluids and mixing in the industrial and chemical industries, because of the nature and properties of these fluids, may be directed to a simply controlled, single-stage process where fluid properties are largely kept unchanged or fluids are mixed over several stages using different levels and types of mixing. For example, to purify water, several stages of cleaning may be required. In a first stage, mixing uses large air bubbles to segregate large particles from water, and in a subsequent stage, smaller bubbles are used to activate and aerate water. What is needed is a mixer, a system of mixing, and a method of mixing capable of easy adaptation to mix fluids in a single- or multistage mixing process and to mix fluids at different velocities with bubbles or laminar flow of different sizes and thicknesses. 
         [0008]    This disclosure incorporates fully herein by reference International Application No. PCT/US2009/033005, entitled Dynamic Mixing of Fluids, and International Application No. PCT/US2009/033000, entitled Method of Dynamic Mixing Fluids. This first family of mixing technologies and devices teaches how two or more fluids, each traveling in different and often opposite directions in conduits, are mixed using reflector-based technology in a quasi-boiling expansion volume. Mixing results from the merging of two fluids in a phase change at the mixing point. 
         [0009]    This disclosure also incorporates fully herein by reference International Application No. PCT/US2008/075378, entitled Foaming of Liquids. This second family of devices teaches how gas bubbles are created and released into an open volume of fluid. Compressed air is split into small flows and is directed sideways into a cavity where liquid is drawn in via forced convection to mix or where radial fins under the flow of incoming bubbles impart a rapid rotational movement and create a vortex in the open volume of fluid. 
         [0010]    What is needed is an improved mixing device capable of creating an auto-initiating vortex and self-sustaining vortex without using moving parts in the mixing device. What is also needed is a device capable of creating a multilayered vortex with stratified portions where fluid and layers of bubbles hash for better mixing under conditions of high turbulence. 
       SUMMARY 
       [0011]    The present disclosure generally relates to a fluid mixer, a system for mixing fluids utilizing the fluid mixer, and a method of mixing fluids using the fluid mixer or the system for mixing fluids, and more specifically, to a compact static mixing device with no moving parts capable of mixing any fluid, such as air, nitrogen gas, water, oil, polluted water, and the like. A first pressurized, incoming fluid is accelerated locally by a section reduction, is split into streams, and is then released into a second fluid found in a closed volume or an open volume after a period of stabilization. The directed and controlled first fluid slides along an insert up to directional and angled fins at a vortex creator where suction forces resulting from a self-initiating vortex in an internal cavity draws in at least part of the first fluid to fuel the vortex. 
         [0012]    The compactness and simplicity of the fluid mixer with internal vortex can be used alone within a closed volume in a conduit, in a sprayer, or within a fixed geometry to direct the mixing vortex to specific dimensions. The fluid mixer can also be used alone or in a group in an open volume such as a reservoir, tank, pool, or other body of fluid to conduct mixing. The technology alone, as part of a multimixer system, or as a method of mixing using the fluid mixer with internal vortex, is intended to be used in any field where mixing occurs. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    Certain embodiments are shown in the drawings. However, it is understood that the present disclosure is not limited to the arrangements and instrumentality shown in the attached drawings. 
           [0014]      FIG. 1  is an illustration of a system for mixing using a plurality of fluid mixers with an internal vortex according to an embodiment of the present disclosure. 
           [0015]      FIG. 2  is a cut-away view of a fluid mixer with internal vortex in an open volume according to an embodiment of the present disclosure. 
           [0016]      FIG. 3  is a perspective view of the fluid mixer of  FIG. 2 . 
           [0017]      FIG. 4  is a partial view of a perspective illustration of the fluid mixer of  FIG. 2  without a possible fixation to an open or closed volume of a second fluid illustrating the displacement of the first fluid and the internal vortex according to an embodiment of the present disclosure. 
           [0018]      FIG. 5  is a partially shadowed perspective view of the fluid mixer of  FIG. 2  where the holder is shadowed. 
           [0019]      FIG. 6  is a perspective view of  FIG. 5  as viewed from a different angle. 
           [0020]      FIG. 7  is a perspective view of the insert as part of the fluid mixer of  FIG. 2  according to an embodiment of the present disclosure. 
           [0021]      FIG. 8  is a front view of a fluid mixer where the vortex creator is disposed within a holding cavity according to another embodiment of the present disclosure. 
           [0022]      FIG. 9  is a view along cut line  9 - 9  as shown in  FIG. 8 . 
           [0023]      FIG. 10  is a perspective view of the insert of the fluid mixer of  FIG. 8 . 
           [0024]      FIG. 11  is a different perspective view of the insert of the fluid mixer of  FIG. 8 . 
           [0025]      FIG. 12  is a partially shadowed perspective illustration of the fluid mixer of  FIG. 8  with functional representation of the first and second fluids according to an embodiment of the present disclosure. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0026]    For the purposes of promoting and understanding the principles disclosed herein, reference is now made to the preferred embodiments illustrated in the drawings, and specific language is used to describe the same. It is nevertheless understood that no limitation of the scope of the invention is hereby intended. Such alterations and further modifications in the illustrated devices and such further applications of the principles disclosed and illustrated herein are contemplated as would normally occur to one skilled in the art to which this disclosure relates. 
         [0027]    Within the scope of this disclosure, the terms “fluid” and “fluids” shall mean a medium made of particles that easily move and change relative position without a separation of the mass and that easily yield to pressure. Fluids can be compressible or incompressible and shall be inclusive of liquids, gases, small particles of solids such as sand or rocks, ionized gases, or any combination thereof. By way of nonlimiting example, a fluid may be a mixture of two or more liquids, a mixture of a liquid with a dissolved gas, or even a liquid with suspended particles or gas bubbles in the liquid. This definition is meant to focus attention on the fact that the term “fluid” is often perceived as a synonym for “liquid.” Within this disclosure, any material that displays fluidic properties falls within the scope of the contemplated embodiment. This definition is not intended to be construed in a limiting way to exclude any material. Further, the terms “vortex” and “vortices” include their ordinary definitions and may also refer to any mass of fluid as defined above having a whirling or circular motion that tends to form a conical or linear structure where at least a portion of the center in the structure is at a depression compared to its rotating edges. 
         [0028]    Commonly known types of vortices in fluid include water drains (liquid and gas vortices), tornados (gas and gas vortices), and powerboat propellers (liquid and liquid vortices). In all three of these examples, mixing is incidental to the creation of vortices. Drain vortices allow for the air to exit pipes as liquid is drained down, but the air is not typically mixed in with the drain water. Tornados serve to exchange high-pressure air with low-pressure air between layers of the atmosphere. Powerboat propellers create a vortex as the propeller rotates in the water and displaces water behind the boat to create forward movement. Blenders and mixers, on the other hand, use vortices more specifically to mix solids with fluids, fluids with fluids, and even gases with liquids. In the examples above, tornados and drain vortices are created as a result of conditions in the fluids, but they are not the result of a dynamic moving part that forces fluids into a more stable configuration. 
         [0029]    One of the numerous principles surrounding the present disclosure is the creation of a vortex in a second fluid made while mixing the first and second fluids and resulting from unique conditions created within the mixing device  100  as shown in  FIGS. 2 and 9 . Flows of the different fluids are placed at unique orientations, thicknesses, and velocities to create in the second fluid a vortex at the vortex creator. By manipulating the different flow conditions, often associated with the characteristics of the fluids, the vortex is altered and calibrated to optimize mixing. For example, in a fluid having a high viscosity, a shorter vortex creator may be required. Calibration of this vortex as part of the mixing device  100  and ultimately the mixing itself does not require undue experimentation by one of ordinary skill in the art. The device  100  is simply placed in any operating condition in contact with any two fluids and the pressure of the first fluid is slowly increased until formation of the vortex is observed. For each contemplated configuration, length and thickness of the different elements may be variable and measured successively. While one embodiment is given, one of ordinary skill in the art understands how the different geometrical parameters, velocities, and angles can changed to create a vortex. 
         [0030]    Further, one of ordinary skill in the art of fluid dynamics recognizes the different principles as applied within the mixing device  100 , such as the laminar and turbulent flow around the structures based on the speed of the flow, the viscosity and temperature of the fluids, and the thicknesses of limiting layers above the different flow surfaces. Further, the mixing device  100  uses the Bernoulli Principle, which states that for an inviscid flow, an increase in the speed of the fluid occurs simultaneously with a decrease in pressure or a decrease in the fluid&#39;s potential energy over a surface. The Bernoulli Principle operates for both compressible and incompressible fluid flows and applies for all fluids contemplated herein. The Bernoulli Principle also stands for a conservation of energy at any position along a streamline where the sum of the kinetic energy and the potential energy of the fluid must remain constant. 
         [0031]      FIG. 1  shows a system  1  for mixing using a plurality of fluid mixers  100  and a system for the control of fluid mixers  100 . A control mechanism  4  representing any industrial and commercial control system is connected to a plurality of fluid mixers  100  installed on different reservoirs  3 ,  4  at different locations. For example, some fluid mixers  100  may be placed on the bottom of the reservoirs  3 ,  4  while others may be placed sideways. Systems  1  with a plurality of tanks may be linked  6  as required in the process. As shown, a plurality of fluid mixers  100  can be placed on a single reservoir  3  or  4 . Finally, a first fluid reservoir  5 , such as a tank of compressed air, is shown to be part of the system  1 .  FIG. 1  represents only one of the many varied types of systems  1  contemplated for the mixing of fluids. 
         [0032]      FIG. 2  shows a fluid mixer  100  with a holder  8  connected to an inlet pipe  7 . The holder includes a fluid inlet  120  and a fluid outlet  121  defining a holding cavity  122  between the fluid inlet  120  and the fluid outlet  121  for the transfer of a first fluid  27  from the fluid inlet  120  to the fluid outlet  121 . As shown in  FIG. 2 , the external surface of the holder  123  may include a fixation means  124  such as threads or stops with a leak-proof edge  125  to place the holder  8  in communication with the second fluid  20  in a reservoir  2 ,  3 . While one type of fixation means is shown, any type of permanent and impermanent fixing means, including but not limited to a holder  8  capable of being disassembled to change and replace the insert  9  into the holder  8 , is contemplated. In one embodiment, the insert  9  is held in place in the holder  8  by the air pressure  27  from the incoming first fluid. As shown in  FIG. 2 , the inlet pipe  7  is a flexible tube slid over a notch made at the fluid inlet  120 . Again, while one method of attachment is shown, any means of attachment or connection is contemplated. 
         [0033]    Further, the holder  8  includes an internal surface  126  in communication with the first fluid  27 . The holder  8 , much like the insert  9 , is made in a preferred embodiment of stainless steel or other metal having a good rigidity and that is not corroded by either the first or second fluids  27 ,  20 . Other materials, such as an inert ceramic, a hardened plastic, a thermoset resin compound over carbon fibers, can also be used. One of ordinary skill in the art recognizes that while other materials are contemplated, flow parameters over these materials, such as surface friction, must be used to calibrate the device properly. 
         [0034]    The fluid mixer  100  further includes an insert  9  with an external surface  127  slid at least partly into the holding cavity  122  as shown and in contact with a second fluid  20 , the insert  9  having a first end  128  and a second end  129  where the second end includes a vortex creator  130 . In one embodiment, the insert  9  also includes an expansion area  26  between the first end  128  and the second end  129 . The expansion area  26  as shown may be at the interface between the internal surface  126  of the holding cavity  122  and the external surface  127  of the insert  9 . The passage area shown as  26  may also be calibrated to create a layer of fluid as illustrated by the arrows where the first fluid  27 , as it exits into the second fluid  20 , is pushed along the surface of the insert  9  and has a fixed thickness at the expansion area for the creation of small volumes of the first fluid  27  such as bubbles having a radius in proportion with the fixed thickness. In one embodiment, the thickness is calibrated between approximately 1 micron and 100 microns. 
         [0035]    Further, the holding cavity  122  may include a means for splitting the first fluid  27  into a plurality of streams as shown by the arrows in  FIG. 4  before entry of the first fluid  27  into the expansion area  26 . Many different means for splitting are contemplated. In one embodiment as shown in  FIGS. 2-7 , the first fluid  27  is split at the first end  128  into a plurality of openings  64  in communication with the expansion area  26 . As shown in greater detail in  FIG. 7 , the plurality of openings is created by a series of slotted elements  65  at the circumference of the insert  9 . The splitting may be initiated at a cone  32 , also located at the first end  128 , to reduce the passage area and thus increase the speed of the first fluid  27 . The first fluid then travels in the openings  64 . A small notch  63  may also be made on in the body  31  of the insert  9 . While one configuration is shown where the slotted elements  65  are located on the insert  9 , other configurations are contemplated, such as the design of the slotted elements as part of the holder  8 , the use of small conduits, or holes drilled into the insert  9 . 
         [0036]    The vortex creator  130  on the insert  9  includes an internal cavity  62  at the second end  129 , the internal cavity  62  being in communication with the second fluid  20 , and includes at least an angled fin  39  for the passage of the first fluid  27  from the external surface of the insert  127  to the internal cavity  62 .  FIG. 7  shows with greater detail the finned area of the insert  9 . A plurality of fins  39  are created on the external periphery of the second end  129 . As shown in  FIG. 8 , radial openings  64  are placed at 45° angles around the second end  129 . The configuration of the fins has a thickness  70  and a variable opening  69  from the external to the internal portion of the insert  9 . As the vortex is created inside insert  9  in the internal cavity  62  as shown in  FIG. 6 , the pressure in the cavity drops and creates an aspiration of the first fluid located on the immediate surface of the insert  9 . While flat and angled fins are shown to impart upon the vortex a rotational energy as the first fluid  27  is drawn in, other passageway configurations are contemplated, such as passageways with small, angled holes or slits made in the middle portion of the insert, etc.  FIGS. 9-12  described later show a different configuration of fins  39  as part of the insert  9 . 
         [0037]    In a preferred embodiment, the first fluid  27  is air, pressurized air, nitrogen gas, pressurized inert gas, or oxygen gas. As the first fluid  27  travels along the insert  9 , the first fluid  27  may undergo an expansion as it enters the second fluid  20 , which may be at a lower absolute or relative pressure. For example, if pressurized air at 15 bars enters the fluid mixer  100  and is ultimately released into a liquid such as water at an absolute pressure of 2 bar (assuming the reservoir has a 10 meter water column), the air expands by a factor of 13. 
         [0038]    Two possible embodiments are shown in  FIGS. 2-7  and  8 - 12 , respectively. The first embodiment is a configuration where second fluid  20  in fluidic contact with the vortex creator  130  is a large open volume such as a tank, a reservoir  2 ,  3 , or other body of water. A vortex created is confined in space by the dynamic movement of water around the vortex. In a second embodiment, a gun  200  is used where the second fluid  27  is in fluidic contact with the vortex creator in a confined portion of a holding cavity. The holder  222  as shown in  FIG. 9  includes an opening  221  for the entry of the second fluid  220  to mix with the first fluid  27 . 
         [0039]      FIG. 9  shows another possible embodiment of the technology described above where a holder  222  includes a first end  229  and a second end  202  where the first end  229  is connected to a connector  201  for the arrival of the first fluid  27 . The first fluid is split into streams  26  and then mixed with the second fluid at  224 . While one input of second fluid is shown, other apertures are contemplated as  224  by altering piece  223 . The insert  210  as shown in  FIGS. 10 and 11  also includes a splitting means made of circumferential segments  232  with openings  233  and associated notches  236 . The first fluid  27  may also expand along the body  230  of the insert  210  before reaching the second fluid  224  and entering the internal cavity  228  via the five fins  226  as shown. A vortex created in the internal cavity  228  is released through the opening  227 . 
         [0040]    As shown, the insert  9  or  210 , depending on the embodiment, is shown as a piece slid into the holders  8  or  222 . An equivalent construction where the insert  9  or  210  is fixed to the holder  8  or  222  or is built from one or a plurality of pieces having the same functionality is also contemplated. In several embodiments, the thickness of the first fluid released into the second fluid varies, and mechanical variations of the different internal and external dimensions of the holder  8  or  222  and/or inserts  9  or  210  are contemplated. Users of a plurality of fluid mixers  100  may remove the connector  7 , pull out the insert  9 , and replace the insert  9  with one having differently sized openings  64 . The fluid mixer  100  is designed to be modular for easy access to the different elements of the device along with the capacity to replace and change the different portions of the device creating the vortex. 
         [0041]    As the first fluid  27  expands from a pressurized state to reach the depressurized state of the second fluid  20 , the fluid  27  may cool via thermodynamic expansion and locally cool a portion of the fluid mixer  100 , such as at the interface between the holder  8  and the insert  9 . This expansion may be used to cool the first fluid  27  as it travels past a portion of the structure cooled. A cooled first fluid  27  then reaches the vortex creator  130  and mixes with the second fluid  20 , thereby cooling the second fluid. 
         [0042]    Air may be used first fluid  27  to aerate the second fluid by mixing air bubbles or other fixed volumes into the second fluid  20 . If using nitrogen gas as the first fluid  27 , the fluid mixer  100  may enrich the second fluid  20  with nitrogen for agricultural applications. In another embodiment, the mixer  100  is used by itself or as part of a system for irrigation of soil where the second fluid  20  is water and the first fluid  27  is a gas mixed in at the vortex creator  130  to alter the properties of water to slow the rate of seepage of water in soil. In another embodiment, the first fluid  27  further includes a fertilizer. 
         [0043]    In other numerous contemplated embodiments, the device  100  for mixing fluid is used as a foam generator and the vortex created by the vortex creator mixes a gas in a second fluid  20  to create a foam. The device for mixing fluid  100  can also be used as a parts washer where the vortex created by the vortex creator is directed onto a part resting in a parts washer immersed in the second fluid  20 . Also, the device  100  for mixing fluids can also be used as an emulsifier where the vortex created by the vortex creator uses a first fluid  27  to emulsify the second fluid  20 . 
         [0044]    The use of a single fluid mixer  100  as shown in  FIG. 2  is described above. The use of a system for mixing using a plurality of fluid mixers  1  as shown figuratively in  FIG. 1  is also contemplated. The system  1  may include at least two fluid mixers  100  where each fluid mixer  100  has a holder  8  with a fluid inlet  120  and a fluid outlet  121  and an insert  9 . The fluid inlets  120  of each fluid mixers  100  are either in contact with a different first fluid  27  or in contact with the same first fluid  27 . If the system includes a single reservoir  2 ,  3 , each insert  9  is connected to a single second fluid  27 , but if the system  1  includes several reservoirs  2 ,  3 , each mixer  100  is in contact with a different second fluid  27 . 
         [0045]    In a fluid mixer system  1 , different requirements may warrant different fluid mixers  100  with different mixing properties. In one embodiment, at least two of the fixed thicknesses of different fluid mixers  100  are different. In another configuration, at least one of the fluid mixers is oriented vertically, and the vortex creator is aligned to create a vortex from the bottom of a surface of the second fluid  20  to the natural surface of the second fluid  20 . 
         [0046]    In the case of the creation of bubbles  35  of the first liquid  27 ,  FIG. 5  shows how these bubbles may partly enter the internal cavity around the edge  24  before they are released outwards  22  along a vortex-like path. Some of the first fluid  27  may also continue outwards and create an external layer of turbulent first fluid  27  surrounding an internal inward flow of second fluid  20 . 
         [0047]    In one embodiment, a method of operation of a mixing system is contemplated, the method comprising the steps attaching at least a fluid mixer  100  to a reservoir  2 ,  3 , placing a volume of the second fluid  20  in the reservoir  2 ,  3  so at least a natural surface of the second fluid covers the internal cavity  62  of the mixer  100 , and connecting a first fluid  27  at the fluid inlet  120  to at least one fluid mixer  8  and allowing the first fluid  27  to travel in the fluid mixer  100  to form a vortex for mixing the first fluid with the second fluid  20  in the reservoir  2 ,  3 . The method may further include the step of attaching a second fluid mixer  100  to the reservoir  2 ,  3  and connecting the first fluid  27  at the fluid inlet  120  of the second fluid mixer  100  to allow the first fluid  7  to travel in the fluid mixer  100  and form a second vortex for mixing the first fluid  27  with the second fluid in the reservoir  2 ,  3 . 
         [0048]    In another method for controlling a system for mixing fluids, the method includes the step of controlling a flow of the first fluid  27  in the fluid mixer  100  using a central control system  4  from a remote location. The control of the flow of the first fluid  27  may be accomplished using an input from a sensor (not shown) for measuring a characteristic of the second fluid  20 . In a multimixer system, the method further include the step of attaching a second fluid mixer  100  to the reservoir  2 ,  3 , connecting the first fluid  27  at the fluid inlet  120  of the second fluid mixer  100 , and controlling the flow of the first fluid  27  at the fluid inlet  120  of the second fluid mixer  100  by the central control system  4 . 
         [0049]    It is understood that the preceding detailed description of some examples and embodiments of the present invention may allow numerous changes to the disclosed embodiments in accordance with the disclosure made herein without departing from the spirit or scope of the invention. The preceding description, therefore, is not meant to limit the scope of the invention but to provide sufficient disclosure to one of ordinary skill in the art to practice the invention without undue burden.