Tangential Air Separator And Flow Balancer For A Closed Fuel Circulation System

Abstract

A combination air eliminator and flow balancer for a fluid circulation system includes a tank having a supply inlet, a supply outlet, a return inlet and a return outlet. The tank defines an interior having a vertical cylindrical configuration. The supply inlet is located above the supply outlet, the return inlet and the return outlet. The supply inlet introduces fluid into an upper portion of the interior of the tank in a tangential direction to induce rotational downward flow between the supply inlet and the supply outlet, which separates air contained within the fluid. The air migrates upwardly within the tank interior and is vented. The tank is capable of balancing flow by 1) returning fluid from the supply inlet to the return outlet without passing through the supply outlet, and 2) returning fluid from the return inlet to the supply inlet without passing through the return outlet,

Description

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of U.S. Provisional Application No. 62/107,784, filed Jan. 26, 2015.

BACKGROUND AND SUMMARY

[0002] This invention relates to a closed fluid circulation system, such as a hydronic heating system, and more particularly to a device for eliminating air from the fluid and for balancing the flow of fluid in the system.

[0003] A closed fluid circulation system typically includes a pump that circulates fluid through a closed conduit arrangement. In a closed hydronic heating system, the pump circulates the fluid first through a boiler or other heating device, and the heated fluid is then supplied to radiators or other such devices for interior heating. The cool fluid is then circulated back to the pump and again through the boiler for reheating.

[0004] It is known that air can become present in the fluid of hydronic heating system, and it is desirable to eliminate the air in order to preserve the integrity of the fluid and to prevent pipe corrosion. Various types of air elimination devices are known, and can be incorporated in the fluid circulation system.

[0005] It is also known that a flow imbalance can occur between the pump output and the return flow of fluid that is supplied to the pump. That is, there can be times when return flow of fluid from the loads to the pump is more than the pump intake can handle, as well as times when the return flow of fluid to the pump is less than the pump requires to provide a desired pump output. To accommodate such a flow imbalance, it is known to provide a flow balancing tank that allows fluid to be short-circuited back to the pump if pump output is more than can be supplied to the loads at a given time and it also allows fluid to be returned to the loads without circulation through the pump if the return flow of fluid from the loads is more than the pump intake can accommodate.

[0006] Is an object of the present invention to provide a device that can be incorporated in a closed fluid circulation system and that is capable of performing both an air elimination function and a flow-balancing function.

[0007] In accordance with the present invention, a combination air eliminator and flow balancer is provided, for a closed fluid circulation system that includes a circulation loop and a pump having an intake and outlet. Representatively, the closed fluid circulation system may be in the form of a hydronic heating system. The combination air eliminator and flow balancer includes a tank positioned between the circulation loop and the pump intake and outlet. The tank includes a supply inlet that receives supply fluid from the pump outlet and a supply outlet that supplies fluid to the circulation loop. The tank further includes a return inlet that receives return fluid from the circulation loop and a return outlet that supplies fluid to the pump intake. The tank defines an interior having a generally cylindrical configuration that extends along a generally vertical axis, and the supply inlet of the tank is located at an elevation above the supply outlet, the return inlet and the return outlet. The supply inlet is positioned in a generally non-radial orientation such that fluid flow is introduced into an upper portion of the interior of the tank in a non-radial flow direction so as to induce rotational downward fluid flow between the supply inlet and the supply outlet, which induces separation of air contained within the fluid. The air migrates upwardly within the interior of the tank, and an air vent interconnected with the tank functions to exhaust air from the tank interior to atmosphere. In addition, the tank is capable of balancing flow by 1) returning fluid from the supply inlet to the return outlet without the fluid passing through the circulation loop, and 2) returning fluid from the return inlet to the supply inlet without the fluid passing through the pump.

[0008] Representatively, the supply inlet may be located on the same side of the tank as the supply outlet, and may be configured so as to define fluid flow paths that are generally parallel to each other. The return inlet and the return outlet may be located on a side of the tank opposite that of the supply inlet and the supply outlet, and may be configured so as to define flow paths that are generally parallel to each other. The return inlet and the return outlet may be configured so as to define flow paths that are generally in alignment with each other. The supply outlet, the return inlet and the return outlet may be positioned at generally the same elevation below the supply inlet.

[0009] The present invention also contemplates a closed fluid circulation system and a method of circulating fluid in a closed fluid circulation system, substantially in accordance with the foregoing summary.

[0010] These, and other aspects and objects of the present invention will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following description, while indicating a representative embodiment of the present invention, is given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] A clear conception of the advantages and features constituting the present invention, and of the construction and operation of typical mechanisms provided with the present invention, will become more readily apparent by referring to the exemplary, and therefore non-limiting, embodiment illustrated in the drawings accompanying and forming a part of this specification, wherein like reference numerals designate the same elements in the several views, and in which:

[0012] FIG. 1 is a schematic view of a closed fluid circulation system incorporating the combination air eliminator and flow balancer in accordance with the present invention;

[0013] FIG. 2 is a top plan view of the combination air eliminator and flow balancer as shown in FIG. 1;

[0014] FIG. 3 is a section view taken along line 3-3 of FIG. 2;

[0015] FIG. 4 is a section view taken along line 4-4 of FIG. 2; and

[0016] FIG. 5 is a schematic view generally illustrating the manner in which fluid flows through the combination air eliminator and flow balancer of FIGS. 2-4.

[0017] In describing the embodiment of the invention which is illustrated in the drawings, specific terminology will be resorted to for the sake of clarity. However, it is not intended that the invention be limited to the specific terms so selected and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose. For example, the words "connected", "attached", or terms similar thereto are often used. They are not limited to direct connection but include connection through other elements where such connection is recognized as being equivalent by those skilled in the art.

DETAILED DESCRIPTION

[0018] The present invention and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments described in detail in the following description.

[0019] FIG. 1 schematically illustrates a closed fluid circulation system, which representatively may be a hydronic heating system. In such a system, a pump P circulates fluid, such as water, through a conduit such as C1 to a boiler B, where the fluid is heated. The heated fluid is then supplied through a supply conduit C2 to a combination air eliminator and flow balancer 10 constructed in accordance with the present invention, from which it is supplied through a supply conduit C3 from air eliminator and flow balancer 10 to a series of heating loads, such as radiators within various rooms or spaces of a building. The cool fluid is then returned to air eliminator and flow balancer 10 through a return conduit C4, and returns to the intake of pump P through a return conduit C5. Air eliminator and flow balancer 10 includes a supply inlet connection 12. a supply outlet connection 14, a return inlet connection 16 and a return outlet connection 18. In a manner as is known, supply inlet connection 12 includes a flanged connection that is flow coupled to supply conduit C2, although it is understood that any other satisfactory fluid flow connection may be employed. Similarly, supply outlet connection 14 is flow coupled to supply conduit C3, return inlet 16 is flow coupled to return conduit C4, and return outlet C5 is flow coupled to return conduit C5.

[0020] Air eliminator and flow balancer 10 includes a body in the form of a shell or tank 20, which includes a generally cylindrical side wall 22, a top wall 24 and a bottom wall 26, which cooperate to define an enclosed volume in the interior of tank 20. In a manner as is known, tank 20 also includes a series of legs 28 for supporting the air eliminator and flow balancer 10 above a support surface, such as a floor.

[0021] Referring to FIGS. 1-3, supply inlet connection 12 is flow coupled to the upstream end of a supply inlet conduit 30, the downstream end of which is flow coupled to tank 20 through a supply inlet opening 32 formed in tank side wall 22. On the same side of tank 20, supply outlet connection 14 is flow coupled to the downstream end of a supply outlet conduit 34, the upstream end of which is flow coupled to tank 20 through a supply outlet opening 36 formed in tank side wall 22.

[0022] As also shown in FIGS. 1-3, return inlet connection 16 is flow coupled to the upstream end of a return inlet conduit 38, the downstream end of which is flow coupled to tank 20 through a return inlet opening 40 formed in tank side wall 22. On the same side of tank 20, return outlet connection 18 is flow coupled to the downstream end of a return outlet conduit 42, the upstream end of which is flow coupled to tank 20 through a return outlet opening 44 formed in tank side wall 22. It can thus be appreciated that the supply inflow to and outflow from tank 20 through supply inlet opening 32 and supply outlet opening 36, respectively, are located on one side of tank 20, and that the return inflow to and outflow from tank 20 through return inlet opening 40 and return outlet opening 44 are on the opposite side of tank 20.

[0023] Referring to FIGS. 3 and 4, the interior of tank 20 is shown generally at 50. Supply inlet opening 32 is located on tank side wall 22 so as to supply fluid from supply inlet conduit 30 into the upper region of tank interior 50. Supply outlet opening 36, on the other hand, is located on tank side wall 22 such that fluid flows outwardly from the tank interior 50 from the lower region of tank interior 50.

[0024] Tank side wall 22 has a generally circular cross-section such that the boundary of tank interior 50 is generally circular. It is understood, however, that the boundary of tank interior 50 need not be perfectly circular, and the tank interior 50 may also have a cross-section that is generally elliptical.

[0025] Supply inlet conduit 30 is oriented relative to tank interior 50 such that fluid flows into the tank interior 50 through supply inlet opening 32 in a non-radial direction. That is. the path of fluid flow into the tank interior 50 is not aligned with a radius of the circle circumscribed by tank side wall 22, but rather is generally parallel to a line that is tangential relative to the periphery of tank side wall 22 (such flow being hereafter referred to as tangential flow). In a similar manner, supply outlet conduit 34 is oriented relative to tank interior 50 such that fluid flows out of the tank interior 50 through supply outlet opening 36 in a non-radial direction, to provide tangential outflow from tank interior 50 in the same manner as tangential inflow is provided through supply inlet opening 32. The tangential fluid inflow through supply inlet conduit 30 is generally parallel to and above the tangential fluid outflow through supply outlet conduit 34.

[0026] Return inlet conduit 38 is oriented relative to tank interior 50 such that fluid flows into the tank interior 50 through return inlet opening 40 in a non-radial direction, to provide tangential inflow to tank interior 50 in the same manner as described above. Similarly, return outlet conduit 42 is oriented relative to tank interior 50 to provide tangential outflow through return outlet opening 44. The flow paths of return inlet conduit 38 and return outlet conduit 42 are also generally parallel to each other. Representatively, in one embodiment as illustrated, the flow paths of return inlet conduit 38 and return outlet conduit 42 are aligned with each other such that return inlet opening 40 and return outlet opening 44 are in direct alignment with each other on opposite sides of tank interior 50.

[0027] Supply inlet conduit 30, supply outlet conduit 34, return inlet conduit 38 and return outlet conduit 42 are oriented so as to provide fluid flow paths that are generally parallel to each other. With this arrangement, the vertically offset parallel flow paths of supply inlet conduit 30 and supply outlet conduit 34, which are located on one side of the centerline of tank 20, are parallel to the flow paths of return inlet conduit 38 and return outlet conduit 42, which are located on the opposite side of the centerline of tank 20. It is understood, however, that while generally parallel flow paths are shown and described, the flow paths may also be non-parallel and non-aligned so long as the general arrangement, orientation and function of the supply and return flow paths is maintained.

[0028] An air vent 52 is mounted to top wall 24 of tank 20 and a drain pipe 54 is mounted to the bottom wall 26 of tank 20. Air vent 52 is constructed and arranged so as to enable air in the upper region of tank interior 52 escape to atmosphere. Drain pipe 54 is employed to selectively empty the contents of tank 20, such as for maintenance, replacement, cleaning, etc.

[0029] FIG. 5 schematically illustrates fluid flow through combination air eliminator and flow balancer 10 in operation. When pump P is operated, heated fluid from boiler B is supplied to supply inlet conduit 30 into the upper region of tank interior 50. Due to the tangential orientation of supply inlet conduit 30 and the curved tank side wall 22, the tangential orientation of such heated fluid inflow causes the incoming fluid stream to circulate within the upper region of tank 20 in a circular manner. The incoming fluid stream then falls by gravity through tank interior 52 create a somewhat downward spiraling flow of fluid within the tank interior 50. As the heated fluid continues to travel through tank interior 50 in a circular path in this manner, it eventually is discharged from tank interior 50 into supply outlet conduit 34 for supply to the heating loads downstream therefrom. After the heated fluid circulates through the heating loads and is cooled, the cool return fluid will is supplied to tank interior 50 through return inlet conduit 38, which as noted above is located in the lower region of tank interior 50 and may be at the same elevation as supply outlet conduit 34. The cooled return fluid travels directly across the volume of tank interior 50 into the return outlet conduit 42. A portion of such fluid may circulate around the lower region of tank 50 before it passes into return outlet conduit 42, but the majority of such fluid will pass directly into the return outlet conduit 42 in a generally linear path from return in the conduit 38. As can be appreciated, the cooled return fluid generally stays in the lower region of tank interior 50 while the supply fluid generally stays in the upper region of tank interior 50.

[0030] As the fluid travels a circular path around the tank interior 50, whether it be the heated fluid in the upper region of tank interior 50 or the cooled fluid in the lower region tank interior 50, the circular, spiral flow of the fluid causes entrapped air contained within the fluid to migrate toward the center of tank interior 50. In FIG. 5, such inwardly migrate entrapped air is represented by air bubbles shown at 60. The entrapped air bubbles 60 migrate upwardly toward the top of tank interior 50, where they can escape tank interior 50 through air vent 52.

[0031] In addition to the air separation function provided by the tangential introduction of fluid and the circular fluid flow path within tank interior 50, tank interior 50 also is capable of providing a flow balancing function if required. That is, tank interior 50 functions as a buffer between pump P and the heating loads. In the event the output from pump P is greater than the loads downstream of tank 20 can accept, the fluid that cannot at that time be circulated to the loads can circulate through the tank interior 50 and be discharged back to pump P through return outlet conduit 42 without going through supply outlet conduit 34 to the heating loads. The excess fluid is essentially shunted back to the pump P to balance against incoming flow from the heating loads. In a similar manner, in the event the output from the heating loads is greater than the intake of pump P can accept, the fluid that cannot at that time be circulated to the pump intake can circulate through the tank interior 50 and be discharged back to the heating loads through supply outlet conduit 34 without going through return outlet conduit 42 to the pump P. The excess fluid is essentially shunted back to the heating loads to balance against incoming flow from the pump P. While this condition is not ideal in that unheated fluid is being supplied to the heat loads, it is nonetheless desirable because a majority of the fluid in supply outlet conduit 34 is heated and because this flow balancing function enables pump P to operate in an efficient and optimal manner.

[0032] The present invention has been shown and described with the inlet and outlet openings of the tank all being formed in the tank sidewall. It should be appreciated, however, that some or all of the inlet and outlet openings may also be formed in the upper and lower end walls of the tank. Other alternative configurations may be employed as desired without departing from the essential air separation and flow balancing functions as set forth above.

[0033] Various additions, modifications and rearrangements are contemplated as being within the scope of the following claims, which particularly point out and distinctly claim the subject matter regarded as the invention, and it is intended that the following claims cover all such additions, modifications and rearrangements.

Claims

1. A combination air eliminator and flow balancer for a closed fluid circulation system that includes a pump having an intake and outlet and a circulation loop, comprising: a tank positioned between the circulation loop and the pump intake and outlet, wherein the tank includes a supply inlet that receives supply fluid from the pump outlet and a supply outlet that supplies fluid to the circulation loop, and further includes a return inlet that receives return fluid from the circulation loop and a return outlet that supplies fluid to the pump intake, wherein the tank defines an interior having a generally cylindrical configuration that extends along a generally vertical axis, and wherein the supply inlet of the tank is located at an elevation above the supply outlet, the return inlet and the return outlet, and wherein the supply inlet is positioned in a generally non-radial orientation such that fluid flow is introduced into an upper portion of the interior of the tank in a non-radial flow direction so as to induce rotational downward fluid flow between the supply inlet and the supply outlet, wherein the rotational downward fluid flow induces separation of air contained within the fluid and wherein the air migrates upwardly within the interior of the tank, and further wherein the tank is capable of balancing flow by 1) returning fluid from the supply inlet to the return outlet without the fluid passing through the circulation loop, and 2) returning fluid from the return inlet to the supply inlet without the fluid passing through the pump; and an air vent interconnected with the tank for exhausting air from the tank interior to atmosphere.

2. The combination air eliminator and flow balancer of claim 1, wherein the supply inlet is located on the same side of the tank as the supply outlet.

3. The combination air eliminator and flow balancer of claim 2, wherein supply inlet and the supply outlet are configured so as to define fluid flow paths that are generally parallel to each other.

4. The combination air eliminator and flow balancer of claim 2, wherein the return inlet and the return outlet are located on a side of the tank opposite that of the supply inlet and the supply outlet.

5. The combination air eliminator and flow balancer of claim 4, wherein the return inlet and the return outlet are configured so as to define flow paths that are generally parallel to each other.

6. The combination air eliminator and flow balancer of claim 5, wherein the return inlet and the return outlet are configured so as to define flow paths that are generally in alignment with each other.

7. The combination air eliminator and flow balancer of claim 5, wherein the supply outlet, the return inlet and the return outlet are at generally the same elevation below the supply inlet.

8. The combination air eliminator and flow balancer of claim 1, wherein the circulation loop comprises a hydronic heating system, and further comprising a fluid thing arrangement interposed between the pump and the supply inlet.

9. A closed fluid circulation system, comprising: a circulation loop; a pump for circulating fluid through the circulation loop, wherein the pump includes an intake and an outlet; and a combination air eliminator and flow balancer interconnected in the circulation loop, comprising a tank positioned downstream of the pump outlet, wherein the tank includes a supply inlet that receives supply fluid from the pump outlet and a supply outlet that supplies fluid to the circulation loop, and further includes a return inlet that receives return fluid from the circulation loop and a return outlet that supplies fluid to the pump intake, wherein the tank defines an interior having a generally cylindrical configuration that extends along a generally vertical axis, and wherein the supply inlet of the tank is located at an elevation above the supply outlet, the return inlet and the return outlet, and wherein the supply inlet is positioned in a generally non-radial orientation such that fluid flow is introduced into an upper portion of the interior of the tank in a non-radial flow direction so as to induce rotational downward fluid flow between the supply inlet and the supply outlet, wherein the rotational downward fluid flow induces separation of air contained within the fluid and wherein the air migrates upwardly within the interior of the tank and wherein the tank includes an air vent for exhausting air from the tank interior to atmosphere, and further wherein the tank is capable of balancing flow by 1) returning fluid from the supply inlet to the return outlet without the fluid passing through the circulation loop, and 2) returning fluid from the return inlet to the supply inlet without the fluid passing through the pump.

10. The closed fluid circulation system of claim 9, wherein the circulation loop comprises a hydronic heating system.

11. The closed fluid circulation system of claim 9, wherein the supply inlet is located on the same side of the tank as the supply outlet.

12. The closed fluid circulation system of claim 11, wherein the supply inlet and the supply outlet are configured so as to define fluid flow paths that are generally parallel to each other.

13. The closed fluid circulation system of claim 11, wherein the return inlet and the return outlet are located on a side of the tank opposite that of the supply inlet and the supply outlet.

14. The closed fluid circulation system of claim 13, wherein the return inlet and the return outlet are configured so as to define flow paths that are generally parallel to each other.

15. The closed fluid circulation system of claim 14, wherein the return inlet and the return outlet are configured so as to define flow paths that are generally in alignment with each other.

16. The closed fluid circulation system of claim 14, wherein the supply outlet, the return inlet and the return outlet are at generally the same elevation below the supply inlet.

17. A method of circulating fluid in a closed fluid circulation system that includes a pump and a circulation loop, comprising the acts of: connecting a tank in the closed fluid circulation system, wherein the tank includes a supply inlet, a supply outlet, a return inlet and a return outlet, wherein the tank defines an interior having a generally cylindrical configuration that extends along a generally vertical axis, and wherein the supply inlet is located at an elevation above the supply outlet, the return inlet and the return outlet; introducing fluid through the supply inlet in a generally non-radial orientation such that fluid flow is introduced into an upper portion of the interior of the tank in a non-radial flow direction so as to induce rotational downward fluid flow between the supply inlet and the supply outlet, wherein the rotational downward fluid flow induces separation of air contained within the fluid and wherein the air migrates upwardly within the interior of the tank; exhausting air from the tank interior to atmosphere; and selectively balancing flow in the fluid circulation system by 1) returning fluid from the supply inlet to the return outlet without the fluid passing through the circulation loop, or 2) returning fluid from the return inlet to the supply inlet without the fluid passing through the pump.

18. The method of claim 17, wherein the circulation loop comprises a hydronic heating system.

19. The method of claim 17, wherein the supply inlet is located on the same side of the tank as the supply outlet.

20. The method of claim 19, wherein the supply inlet and the supply outlet are configured so as to define fluid flow paths that are generally parallel to each other.

21. The method of claim 19, wherein the return inlet and the return outlet are located on a side of the tank opposite that of the supply inlet and the supply outlet.

22. The method of claim 21, wherein the return inlet and the return outlet are configured so as to define flow paths that are generally in alignment with each other.

23. The method of claim 17, wherein the supply outlet, the return inlet and the return outlet are at generally the same elevation below the supply inlet.